You searched for subject:(Nanowire).
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Penn State University
1.
Kim, Jaekyun.
Deterministic Assembly of Functional Nanodevices onto
Silicon Circuits.
Degree: PhD, Electrical Engineering, 2010, Penn State University
URL: https://etda.libraries.psu.edu/catalog/10557 
► Bottom-up integration of nanostructures offers a promising method to achieve material diversity for chemical and biological applications, often considered unattainable by conventional top-down fabrication. Thus,…
(more)
▼ Bottom-up integration of nanostructures offers a
promising method to achieve material diversity for chemical and
biological applications, often considered unattainable by
conventional top-down fabrication. Thus, deterministic integration
of nanostructures such as nanowires and nanoshell spheres on
silicon CMOS circuitry represents a significant step toward
cross-reactive silicon CMOS chip where different types of off-chip
synthesized sensory materials are merged. Applying this
deterministic bottom-up integration to substrate or circuit
eliminates the constraints of thermal budget, chemical
compatibility, lattice mismatch between nanostructures to be
assembled and substrate. This thesis discusses a deterministic
assembly strategy for nanowires and spheres and their integrations
onto silicon CMOS circuitry for electronic microsystem
applications. The nanowire assembly structure was designed to
create a dielectrophoretic attractive force toward the electrode
gap, resulting in uniformly-spaced rhodium nanowire array due to
mutual electrostatic interaction between assembled nanowires.
Systematic investigation reagarding nanowire array formation
reveals that stronger long-range dielectrophoretic forces attract
more nanowires at the electrode gap, forming less-spaced array
while stronger electrostatic nanowire interaction results in the
larger spacing within the array. Thus, their interplay tends to
determine the average spacing between the assembled nanowires.
Based on understanding the electrostatistic interaction between
assembled nanowires, lithographically defined wells with a
localized electric field determines the final alignment position of
assembled rhodium nanowires on a substrate. Post-assembly process
using electrodeposition and subsequent lift-off process completes
monolithic integration of rhodium nanowires while preserving
nanowires assembled only within the recessed region. Individual
rhodium nanowire assembly yields exceeding 95% were obtained at
nanowire densities >105 /cm2 with a submicron registration
accuracy. PEDOT/ClO4 nanowire chemical sensors are also fabricated
to demonstrate functional nanowire integration for on-chip sensing.
This thesis also describes a bottom-up strategy for fabricating
ultra-high-density cross-point sensor arrays (>107 elements/cm2)
that uses fluidic assembly to position the functional nanoshell
microspheres between lithographically-defined electrodes on-chip.
Cross-point array structure is designed to accommodate single
spherical particles at each cross-point and make them electrically
connected to upper and lower access electrodes. As
proof-of-concept, PEDOT nanoshell microspheres are assembled to
fabricate chemical sensor devices for on-chip application.
Individually addressing each PEDOT nanoshell sphere enables
monitoring of an array of sphere for conductance change by chemical
gas, solvent, humidity. Due to upper and lower electrodes format
and intrinsic form factor of spheres, it is advantageous to achieve
high integration density compared to nanowires with a high…
Subjects/Keywords: Nanotechnology; Nanowire
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APA (6th Edition):
Kim, J. (2010). Deterministic Assembly of Functional Nanodevices onto
Silicon Circuits. (Doctoral Dissertation). Penn State University. Retrieved from https://etda.libraries.psu.edu/catalog/10557
Chicago Manual of Style (16th Edition):
Kim, Jaekyun. “Deterministic Assembly of Functional Nanodevices onto
Silicon Circuits.” 2010. Doctoral Dissertation, Penn State University. Accessed December 13, 2018.
https://etda.libraries.psu.edu/catalog/10557.
MLA Handbook (7th Edition):
Kim, Jaekyun. “Deterministic Assembly of Functional Nanodevices onto
Silicon Circuits.” 2010. Web. 13 Dec 2018.
Vancouver:
Kim J. Deterministic Assembly of Functional Nanodevices onto
Silicon Circuits. [Internet] [Doctoral dissertation]. Penn State University; 2010. [cited 2018 Dec 13].
Available from: https://etda.libraries.psu.edu/catalog/10557.
Council of Science Editors:
Kim J. Deterministic Assembly of Functional Nanodevices onto
Silicon Circuits. [Doctoral Dissertation]. Penn State University; 2010. Available from: https://etda.libraries.psu.edu/catalog/10557
University of Waterloo
2.
Vafaei, Arash.
Simple, economical methods for electrical access to nanostructures used for characterizing and welding individual silver nanowires.
Degree: 2013, University of Waterloo
URL: http://hdl.handle.net/10012/7825
► Elongated nanostructures have attracted a great deal of interest due to unique optical, electrical and physical properties. In particular, silver nanowires and nanobeams have proven…
(more)
▼ Elongated nanostructures have attracted a great deal of interest due to unique optical, electrical and physical properties. In particular, silver nanowires and nanobeams have proven to be top contenders for a variety of applications. Due to their nano-sized dimensions, however, electrical access to individual nanowires is difficult and expensive. Here, a simple and economical procedure was designed to electrically contact small elongated structures using common facilities available at most universities. A common lithographic procedure is used to pattern gold pads and electrodes on top of nanowires already dispersed on a substrate.
This process is tested by first characterizing, using a 4-point-probe measurement, a novel nanobeam created by fusing silver nanodisks. The resistivity of the nanobeams was found to be as low as 2.7x10^−8 Ω·m, which is only slightly above that of bulk silver. These measurements corroborate modeling done by another group that the nanodisks align to create a nearly continuous crystal rather than disjointed grains.
In the second application, Joule-heating was used to actualize a reliable weld between silver nanowires synthesized using the polyol method. The nanowires were situated in series between two metal pads, and a procedure was designed to use electrical current to break down intermediate layers without destroying the nanowires themselves.
In the last enterprise, individual silver nanowires were isolated between two gold pads and then using the same electrical recipe used for welding nanowires, the contact resistance was reduced to a negligible portion of its original value. It was found that due to the reduction in contact resistance, the 2-point-probe resistivity of the nanowire was similar to those conducted using 4 probes. The invented procedure can thus allow accurate resistivity measurements of individual metal nanowires to be done with only 2 contacts rather than 4, thereby simplifying contact fabrication and allowing appropriate contacts to be deposited on nanowires as short as 4 μm using standard photolithography.
Subjects/Keywords: nanowire; nanowelding
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APA (6th Edition):
Vafaei, A. (2013). Simple, economical methods for electrical access to nanostructures used for characterizing and welding individual silver nanowires. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/7825
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Vafaei, Arash. “Simple, economical methods for electrical access to nanostructures used for characterizing and welding individual silver nanowires.” 2013. Thesis, University of Waterloo. Accessed December 13, 2018.
http://hdl.handle.net/10012/7825.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Vafaei, Arash. “Simple, economical methods for electrical access to nanostructures used for characterizing and welding individual silver nanowires.” 2013. Web. 13 Dec 2018.
Vancouver:
Vafaei A. Simple, economical methods for electrical access to nanostructures used for characterizing and welding individual silver nanowires. [Internet] [Thesis]. University of Waterloo; 2013. [cited 2018 Dec 13].
Available from: http://hdl.handle.net/10012/7825.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Vafaei A. Simple, economical methods for electrical access to nanostructures used for characterizing and welding individual silver nanowires. [Thesis]. University of Waterloo; 2013. Available from: http://hdl.handle.net/10012/7825
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
3.
Debnath, Ananya.
The Effect of Nitrogen Plasma Species on the Growth Morphology and Mechanism of Gan Nanocolumns Deposited by Plasma-Assisted Molecular-Beam Epitaxy.
Degree: Physics, Department of, 2015, University of Houston
URL: http://hdl.handle.net/10657/2003
► This dissertation addresses GaN nanocolumns (NCs) growth on Si (111) via a SixNy intermediate layer by radio-frequency molecular-beam epitaxy. In the existing literature, the GaN…
(more)
▼ This dissertation addresses GaN nanocolumns (NCs) growth on Si (111) via a SixNy intermediate layer by radio-frequency molecular-beam epitaxy. In the existing literature, the GaN NC’s morphology was shown to be influenced by growth parameters such as Ga flux, substrate type, growth temperature, buffer layer types, sticking coefficient of Ga adatoms in different planes, etc. The one aspect that so far has been understudied is the role of the plasma-generated species. Due to the multiple states and concentrations of the available excited species in a nitrogen plasma, it has been difficult to quantify and correlate their role with the morphology of the resulting NCs. To address this issue, the nitrogen plasma source has been investigated by optical emission spectroscopy, in order to quantify the relative abundances of the molecular and atomic nitrogen species, and then to examine the effect of these species on the growth morphology and mechanism of GaN NCs grown on Si (111). The length, diameter, and density of NCs were analyzed as a function of the nitrogen species Cmol/Cat concentration ratio during epitaxy. Growth rate and diameter are found to increase and density to decrease up to a certain value of Cmol/Cat nitrogen ratio but plateaued beyond that. The effect of the Cmol/Cat nitrogen ratio seems to be an additional factor that has to be taken into account in the modeling of GaN NC growth. The structural and optical characterization of GaN NCs by PL, XRD, and RHEED show that GaN NC samples are strained. This strain decreases with increasing Cmol/Cat ratio. The growth mechanism of the GaN NCs was investigated in terms of Cmol/Cat ratio using the SEM and TEM results. Under our growth conditions, the NC growth appeared to be driven by direct impingement of adatoms rather than diffusion. The NCs have a core shell structure where the difference in growth rate of shell and core diminishes as Cmol/Cat ratio increases, which results in NCs with different radial growth rates.
Advisors/Committee Members: Varghese, Oomman (advisor), Bensaoula, Abdelhak (committee member), Wood, Lowell T. (committee member), Stokes, Donna (committee member), Forrest, Rebecca L. (committee member), Trombetta, Len (committee member).
Subjects/Keywords: Epitaxy; nanowire
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APA (6th Edition):
Debnath, A. (2015). The Effect of Nitrogen Plasma Species on the Growth Morphology and Mechanism of Gan Nanocolumns Deposited by Plasma-Assisted Molecular-Beam Epitaxy. (Thesis). University of Houston. Retrieved from http://hdl.handle.net/10657/2003
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Debnath, Ananya. “The Effect of Nitrogen Plasma Species on the Growth Morphology and Mechanism of Gan Nanocolumns Deposited by Plasma-Assisted Molecular-Beam Epitaxy.” 2015. Thesis, University of Houston. Accessed December 13, 2018.
http://hdl.handle.net/10657/2003.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Debnath, Ananya. “The Effect of Nitrogen Plasma Species on the Growth Morphology and Mechanism of Gan Nanocolumns Deposited by Plasma-Assisted Molecular-Beam Epitaxy.” 2015. Web. 13 Dec 2018.
Vancouver:
Debnath A. The Effect of Nitrogen Plasma Species on the Growth Morphology and Mechanism of Gan Nanocolumns Deposited by Plasma-Assisted Molecular-Beam Epitaxy. [Internet] [Thesis]. University of Houston; 2015. [cited 2018 Dec 13].
Available from: http://hdl.handle.net/10657/2003.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Debnath A. The Effect of Nitrogen Plasma Species on the Growth Morphology and Mechanism of Gan Nanocolumns Deposited by Plasma-Assisted Molecular-Beam Epitaxy. [Thesis]. University of Houston; 2015. Available from: http://hdl.handle.net/10657/2003
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
4.
Le, Son T.
GERMANIUM AND SIGE NANOWIRE TUNNELING TRANSISTORS AND SOLAR
CELLS.
Degree: PhD, Physics, 2014, Brown University
URL: https://repository.library.brown.edu/studio/item/bdr:386127/
► As the CMOS downscaling continues, the requirements for lower power supply voltage and power consumption become more stringent. New device operating principles and new material…
(more)
▼ As the CMOS downscaling continues, the requirements
for lower power supply voltage and power consumption become more
stringent. New device operating principles and new material
platforms are being explored. Among them, band to band tunneling
and vapor-liquid-solid grown semiconductor hetero-nanowires
(hetero-NWs) are promising candidates as a new device operating
principle and a new material platform for future high-performance
switching devices, respectively. This thesis focuses on exploring
the possibility of utilizing Ge and SiGe nanowires for tunneling
field effect transistors (TFETs). Similar SiGe hetero-NW material
is also studied for photovoltaic applications. First, we explore Ge
NWs, where strong back-gate modulation of band-to-band tunneling in
the axial p-n junction was characterized and modeled. Top-gated Ge
NW TFETs shows promisingly high ION~20 μA/μm current with the
possibility of achieving better subthreshold slope and ION/IOFF
current ratio by improved surface passivation. Second, axial SiGe
hetero-NW TFETs with ~50 mV/decade subthreshold slope were grown,
fabricated, characterized and confirmed by 3D TCAD simulation.
These devices exhibited record Si-compatible TFET performance, with
high ION ~2 µA/μm and ~5 orders of magnitude ION/IOFF ratio. The
same devices could be operated in standard NW FET mode with good
performance. Finally, we explore the possibility of employing axial
p-i-n/p-i-n junction SiGe hetero-NWs as broad-spectrum tandem solar
cells. Preliminary numerical and experimental studies were carried
out for axial p-i-n Si NWs, axial p-n Ge NWs, and axial p-i-n/p-i-n
SiGe hetero-NWs to characterize device performance. The thesis
concludes with future directions, including the possibility of a
novel SiGe hetero-NW electroluminescent optical
source.
Advisors/Committee Members: Alexander, Zaslavsky (Director), Humphrey, Maris (Reader), James, Valles (Reader).
Subjects/Keywords: Germanium nanowire
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APA (6th Edition):
Le, S. T. (2014). GERMANIUM AND SIGE NANOWIRE TUNNELING TRANSISTORS AND SOLAR
CELLS. (Doctoral Dissertation). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:386127/
Chicago Manual of Style (16th Edition):
Le, Son T. “GERMANIUM AND SIGE NANOWIRE TUNNELING TRANSISTORS AND SOLAR
CELLS.” 2014. Doctoral Dissertation, Brown University. Accessed December 13, 2018.
https://repository.library.brown.edu/studio/item/bdr:386127/.
MLA Handbook (7th Edition):
Le, Son T. “GERMANIUM AND SIGE NANOWIRE TUNNELING TRANSISTORS AND SOLAR
CELLS.” 2014. Web. 13 Dec 2018.
Vancouver:
Le ST. GERMANIUM AND SIGE NANOWIRE TUNNELING TRANSISTORS AND SOLAR
CELLS. [Internet] [Doctoral dissertation]. Brown University; 2014. [cited 2018 Dec 13].
Available from: https://repository.library.brown.edu/studio/item/bdr:386127/.
Council of Science Editors:
Le ST. GERMANIUM AND SIGE NANOWIRE TUNNELING TRANSISTORS AND SOLAR
CELLS. [Doctoral Dissertation]. Brown University; 2014. Available from: https://repository.library.brown.edu/studio/item/bdr:386127/
5.
Hsu, Chih-Hsun.
Realization of New Form of Carbon-Diamond
Nanowire – Synthesis, Characterization and Applications.
Degree: PhD, Electrical Science and Computer
Engineering, 2010, Brown University
URL: https://repository.library.brown.edu/studio/item/bdr:11151/
► This dissertation focuses on the synthesis and validation of a new form of carbon, diamond nanowire, which was grown in an atmospheric pressure chemical vapor…
(more)
▼ This dissertation focuses on the synthesis and
validation of a new form of carbon, diamond
nanowire, which was
grown in an atmospheric pressure chemical vapor deposition (CVD)
process. These diamond nanowires are straight, thin and long, and
uniform in diameter (60-90 nm) over the entire lengths of tens of
microns. Spectroscopic analysis, electron diffraction and
transmission electron microscopy provided confirmation that these
nanowires are diamond with high crystallinity and high structural
uniformity. They further revealed that these diamond nanowires are
encased within multi-walled carbon nanotubes. Single
nanowire field
emission measurements revealed that the diamond
nanowire possesses
excellent field emission characteristics such as a high field
enhancement factor (orders of magnitude) and low threshold field
(four times lower) compared to the best known published results on
carbon nanotube. We successfully transferred nanowires from the
original substrate onto oxidized silicon and patterned contacts
with electron beam lithography. The nanowires are expected to
perform as UV detection devices after the device fabrication
development is finished. Besides the CVD synthesis route, diamond
nanowires were also fabricated using a reactive ion etching (RIE)
process. This method allows for reliable control of the shape,
length, diameter, density, and doping of the diamond nanowires.
Finally, we demonstrated the fabrication of a laterally aligned
diamond
nanowire array using Atomic Image Projection E-beam
Lithography (AIPEL) technique. The large surface to volume ratio,
as well as the ultra-high packing density of the nanowires make it
an excellent candidate for application to UV
detection.
Advisors/Committee Members: Xu, Jimmy (Director), Tripathi, Anubhav (Reader), Zia, Rashid (Reader).
Subjects/Keywords: Diamond Nanowire
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APA (6th Edition):
Hsu, C. (2010). Realization of New Form of Carbon-Diamond
Nanowire – Synthesis, Characterization and Applications. (Doctoral Dissertation). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:11151/
Chicago Manual of Style (16th Edition):
Hsu, Chih-Hsun. “Realization of New Form of Carbon-Diamond
Nanowire – Synthesis, Characterization and Applications.” 2010. Doctoral Dissertation, Brown University. Accessed December 13, 2018.
https://repository.library.brown.edu/studio/item/bdr:11151/.
MLA Handbook (7th Edition):
Hsu, Chih-Hsun. “Realization of New Form of Carbon-Diamond
Nanowire – Synthesis, Characterization and Applications.” 2010. Web. 13 Dec 2018.
Vancouver:
Hsu C. Realization of New Form of Carbon-Diamond
Nanowire – Synthesis, Characterization and Applications. [Internet] [Doctoral dissertation]. Brown University; 2010. [cited 2018 Dec 13].
Available from: https://repository.library.brown.edu/studio/item/bdr:11151/.
Council of Science Editors:
Hsu C. Realization of New Form of Carbon-Diamond
Nanowire – Synthesis, Characterization and Applications. [Doctoral Dissertation]. Brown University; 2010. Available from: https://repository.library.brown.edu/studio/item/bdr:11151/
6.
Hui, Ho Yee.
Understand and advancing of semiconductor nanowire synthesis.
Degree: PhD, Chemical and Biomolecular Engineering, 2017, Georgia Tech
URL: http://hdl.handle.net/1853/58314
► Semiconductor nanowires (NWs) have become an indispensable nanoscale platform for a broad range of electronic, photonic, and energy conversion applications. Among all growth technique, the…
(more)
▼ Semiconductor nanowires (NWs) have become an indispensable nanoscale platform for a broad range of electronic, photonic, and energy conversion applications. Among all growth technique, the bottom-up vapor-liquid-solid (VLS)
nanowire (NW) fabrication technique offers the ability to encode material functionalities along the length of a NW in a user programmable manner. A robust control of VLS growth requires understanding of multiple heterogeneous chemical processes: (1) transportation of semiconductor molecules/atoms from vapor to liquid droplets or vice versa at the vapor-liquid (VL) interface, (2) crystallization and dissolution of semiconductor atoms at the liquid-solid (LS) interface, and (3) the conformal deposition of precursor molecules onto the
nanowire sidewall at the vapor-solid (VS) interface. However, the ability to rationally engineer NWs for advanced semiconductor devices is critically impaired by limited understanding of these chemical processes at the heterogeneous interfaces. Here, through experiments and modeling, nanowires can be selectively removed via solid-liquid-vapor mechanism at the VL and LS interfaces. Similarly, the importance of adsorbates from a prior study at the VS interface is leveraged to fabricate large-area arrays of high quality axial Si/Ge heterostructures for the first time. These findings open the door to engineer
nanowire structures along the
nanowire length, a capability that can be applied to applications from high performance electronics to ultra-sensitivities (bio) molecular sensors.
Advisors/Committee Members: Filler, Michael A. (advisor), Reichmanis, Elsa (committee member), Grover, Martha A. (committee member), Xia, Younan (committee member), Bassiri-Gharb, Nazanin (committee member).
Subjects/Keywords: Semiconductor nanowire; Nanomaterial
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APA (6th Edition):
Hui, H. Y. (2017). Understand and advancing of semiconductor nanowire synthesis. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/58314
Chicago Manual of Style (16th Edition):
Hui, Ho Yee. “Understand and advancing of semiconductor nanowire synthesis.” 2017. Doctoral Dissertation, Georgia Tech. Accessed December 13, 2018.
http://hdl.handle.net/1853/58314.
MLA Handbook (7th Edition):
Hui, Ho Yee. “Understand and advancing of semiconductor nanowire synthesis.” 2017. Web. 13 Dec 2018.
Vancouver:
Hui HY. Understand and advancing of semiconductor nanowire synthesis. [Internet] [Doctoral dissertation]. Georgia Tech; 2017. [cited 2018 Dec 13].
Available from: http://hdl.handle.net/1853/58314.
Council of Science Editors:
Hui HY. Understand and advancing of semiconductor nanowire synthesis. [Doctoral Dissertation]. Georgia Tech; 2017. Available from: http://hdl.handle.net/1853/58314
Penn State University
7.
Winter, Christopher Aylwin.
Improvement and Investigation of Silicon Nanowire
"Grow-In-Place" Approach.
Degree: MS, Engineering Science, 2011, Penn State University
URL: https://etda.libraries.psu.edu/catalog/11658
► For nearly a decade silicon nanowires have been the subject of intense research. Future integration of silicon nanowires into commercial devices requires the development and…
(more)
▼ For nearly a decade silicon nanowires have been the
subject of intense research. Future integration of silicon
nanowires into commercial devices requires the development and
further refinement of methods for synthesizing and assembling these
nanowires into densely packed rational structures with high
accuracy and repeatability. Current methods have two broad
classifications: “grow-and-place” and “grow-in-place”. The former
procedure involves forming the nanowires away from their final
orientation, harvesting them from this growth area, and finally
placing them in desired positions. The latter procedure sidesteps
the problems associated with the harvesting and placement steps of
the “grow-and-place” method by forming the nanowires in their final
preferred arrangement. In this thesis, we propose a novel
self-assembling variation of the “grow-in-place” approach for SiNW
growth where the interfacial area of the nanochannel template
interface can be formed out of various materials. This research has
improved on our group’s previous in-template “grow-in-place”
approach by growing SiNWs with smooth morphology and good
electrical properties upon partial exposure while still retaining
the benefits of the original “grow-in-place” approach, including
good control of the SiNW size, number, orientation, position, and
shape. The SiNWs grown using this approach were found to be
morphologically smooth, composed of crystalline silicon and
exhibited good electrical characteristics. Additionally, in this
thesis we explore the use of a metal adhesion layer as a means of
controlling SiNW electrical characteristics. Specifically, this
thesis compared iii electrical characteristics of SiNWs grown using
aluminum or titanium as an adhesion layer versus SiNWs grown
without an adhesion layer and found that the SiNWs grown with
aluminum or titanium as an adhesion layer were, on average, 6 or 9
times, respectively, more conductive than the SiNWs grown without
an adhesion layer. Finally, this thesis presents evidence that
nanowires grown using built-in platinum contacts form in a
dual-material structure. This evidence is in the form of high-
magnification FESEM images. It is suggested that, in the
inter-contact region, the platinum silicide grew as the “shell” of
the nanowire structure and that the core remained silicon because
of the physical configuration of the nanochannel.
Subjects/Keywords: silicon nanowire; growth
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APA ·
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Manager
APA (6th Edition):
Winter, C. A. (2011). Improvement and Investigation of Silicon Nanowire
"Grow-In-Place" Approach. (Masters Thesis). Penn State University. Retrieved from https://etda.libraries.psu.edu/catalog/11658
Chicago Manual of Style (16th Edition):
Winter, Christopher Aylwin. “Improvement and Investigation of Silicon Nanowire
"Grow-In-Place" Approach.” 2011. Masters Thesis, Penn State University. Accessed December 13, 2018.
https://etda.libraries.psu.edu/catalog/11658.
MLA Handbook (7th Edition):
Winter, Christopher Aylwin. “Improvement and Investigation of Silicon Nanowire
"Grow-In-Place" Approach.” 2011. Web. 13 Dec 2018.
Vancouver:
Winter CA. Improvement and Investigation of Silicon Nanowire
"Grow-In-Place" Approach. [Internet] [Masters thesis]. Penn State University; 2011. [cited 2018 Dec 13].
Available from: https://etda.libraries.psu.edu/catalog/11658.
Council of Science Editors:
Winter CA. Improvement and Investigation of Silicon Nanowire
"Grow-In-Place" Approach. [Masters Thesis]. Penn State University; 2011. Available from: https://etda.libraries.psu.edu/catalog/11658
University of Southern California
8.
Madaria, Anuj Rahul.
Synthesis, characterization and application of metal and
semiconductor nanowires.
Degree: PhD, Materials Science and Engineering, 2012, University of Southern California
URL: http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll3/id/203024/rec/6284
► Nanostructured materials such as nanowires have attracted significant attention in the past two decades. Both metallic and semiconducting nanowires have been demonstrated as important building…
(more)
▼ Nanostructured materials such as nanowires have
attracted significant attention in the past two decades. Both
metallic and semiconducting nanowires have been demonstrated as
important building blocks for numerous electronic and
optoelectronic device applications. In this thesis, we have
demonstrated a scalable route for synthesizing vertically aligned
semiconducting nanowires using nanosphere lithography (NSL)
technique in combination with selected area metal organic chemical
vapor deposition (SA-MOCVD). Comparable optical properties were
observed between the nanowires produced by NSL patterning technique
and nanowires produced by using more expensive and slow electron
beam lithography. We have also used capacitance-voltage measurement
technique to determine the doping level in these
nanowire arrays.
In metallic nanowires, we have demonstrated fabrication of high
performance transparent conductive electrodes by using Ag nanowires
and proposed a technique to synthesis thin Ag nanowires which can
have applications in various optoelectronic devices. ❧ This
dissertation describes the above-mentioned aspects in detail and
accordingly consists of seven chapters. Following an overview and
an introduction of fundamental knowledge of nanolithography and
transparent conductive electrodes in Chapter 1, Chapter 2 discusses
the scalable nanosphere lithography patterning and selected area
growth of vertically aligned GaAs
nanowire arrays, a route towards
optimized optical absorption and reflection. ❧ Chapter 3 discusses
the continued work on GaAs
nanowire array and employs the use of
capacitance-voltage measurement technique to determine the doping
level of these nanowires which is important for using these
nanowires for fabrication of any electronic devices. ❧ Chapter 4
deals with an important issue of replacement of traditional ITO as
a transparent conductive electrode (TCE) for optoelectronic
devices. There is a need for replacement of ITO due to several
drawback associated with ITO as will be discussed in detail in the
chapter. We demonstrate the viability of silver
nanowire based
random network film as a potential replacement. We achieve
remarkable performance in terms of sheet resistance and
transparency which rivals that of ITO, supporting a very strong
case for Ag
nanowire film. We combine traditional spray coating
technique with novel Ag nanowires to fabricate high performance
TCE. In chapter 5, we further improve the performance of the TCE
produced by Ag nanowires by using a dry transfer technique
demonstrating a performance comparable to ITO and much better than
other potential candidates that can be used as TCE. ❧ In chapter 6
we addressed an important issue associated with using Ag nanowires
as a future candidate for TCE by proposing a technique to synthesis
thin Ag nanowires which can find application in optoelectronic
device. ❧ Finally in chapter 7, we conclude by discussing the
future directions and work that needs to be done in order to carry
forward the advance made in this thesis.
Advisors/Committee Members: Zhou, Chongwu (Committee Chair), Dapkus, Paul Daniel (Committee Member), Goo, Edward (Committee Member).
Subjects/Keywords: nanowire; semiconductor; metal
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APA (6th Edition):
Madaria, A. R. (2012). Synthesis, characterization and application of metal and
semiconductor nanowires. (Doctoral Dissertation). University of Southern California. Retrieved from http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll3/id/203024/rec/6284
Chicago Manual of Style (16th Edition):
Madaria, Anuj Rahul. “Synthesis, characterization and application of metal and
semiconductor nanowires.” 2012. Doctoral Dissertation, University of Southern California. Accessed December 13, 2018.
http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll3/id/203024/rec/6284.
MLA Handbook (7th Edition):
Madaria, Anuj Rahul. “Synthesis, characterization and application of metal and
semiconductor nanowires.” 2012. Web. 13 Dec 2018.
Vancouver:
Madaria AR. Synthesis, characterization and application of metal and
semiconductor nanowires. [Internet] [Doctoral dissertation]. University of Southern California; 2012. [cited 2018 Dec 13].
Available from: http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll3/id/203024/rec/6284.
Council of Science Editors:
Madaria AR. Synthesis, characterization and application of metal and
semiconductor nanowires. [Doctoral Dissertation]. University of Southern California; 2012. Available from: http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll3/id/203024/rec/6284
Victoria University of Wellington
9.
Burke-Govey, Conor Patrick.
ZnO nanowires and their application in field-effect transistors.
Degree: 2018, Victoria University of Wellington
URL: http://hdl.handle.net/10063/6927
► ZnO nanowires have shown great promise as a semiconducting material for a variety of different electronic applications at the nanoscale, and can be easily synthesised…
(more)
▼ ZnO nanowires have shown great promise as a semiconducting material for a variety of different electronic applications at the nanoscale, and can be easily synthesised at low temperatures using the hydrothermal growth method. However, efforts to reliably produce field-effect transistors (FETs) using ZnO nanowires have been hampered by excessive charge carriers, requiring high temperature annealing (≥400°C) at the expense of the low-temperature synthesis before field dependence is achieved. This thesis presents hydrothermally synthesised ZnO nanowires which can effectively be used as FETs in dry and liquid environments without requiring any annealing or post-growth processing.
The role of polyethylenimine (PEI) in the hydrothermal growth of vertical ZnO nanowires is thoroughly investigated. PEI is a polymer used to increase the aspect ratio of ZnO nanowires, but the molecular weight of the polymer and interactions with other growth precursors are often overlooked. Using 4 mM of PEI(MW = 1300 g/mol) results in hierarchical nanowires, consisting of large primary nanowires which abruptly terminate in thinner secondary nanowires. The secondary nanowires, with lengths of up to 10 m and diameters below 50 nm, are synthesised during a PEI-mediated secondary growth phase, where Zn-PEI complexes continue to provide Zn²⁺ ions after the bulk of the precursors have been exhausted.
The PEI-mediated synthesis of hierarchical nanowires is used to fabricate FETs by laterally growing intersecting networks of nanowires from spaced pairs of ZnO/Ti films, which have been patterned on SiO₂/Si device substrates. All of these FETs show marked field dependence between VG = -10 V to 10 V, despite being used without annealing. Typical on-off ratios are between 10³ - 10⁵, with threshold voltages between -7.5 V to 5 V. This is a significant result, as the majority of ZnO
nanowire FETs reported in the literature require high temperature annealing. Persistent photoconductivity measurements indicate that surface states on the nanowires contribute to the intrinsic field dependence of the devices.
Hierarchical nanowires are also synthesised by modular primary and secondary hydrothermal growths. FETs fabricated using these hierarchical nanowires show less field dependence than PEI-mediated hierarchical nanowires, with limited function ality when used in air. The best FET measured in air operates with an on-off ratio of 10⁴ and a threshold voltage of ~ 0 V. Devices which are field-independent in air can be reliably gated by measuring the FETs in a wet environment, using de-ionised water as a dielectric. A back-gated wet FET operates with an on-off ratio of 105 and a threshold voltage of ~ 8 V. Top-gated wet FETs operate with on-off ratios within 103 - 104, and threshold voltages within 0.4 - 0.9 V. These devices also have significantly low subthreshold swings, on the order of 80 mV/decade.
FETs are fabricated by contacting individual ZnO nanowires using electron-beam lithography, although only one vertical ZnO
nanowire shows field dependence, with…
Advisors/Committee Members: Plank, Natalie, Trodahl, Joe.
Subjects/Keywords: ZnO; Nanowire; Transistor
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APA (6th Edition):
Burke-Govey, C. P. (2018). ZnO nanowires and their application in field-effect transistors. (Doctoral Dissertation). Victoria University of Wellington. Retrieved from http://hdl.handle.net/10063/6927
Chicago Manual of Style (16th Edition):
Burke-Govey, Conor Patrick. “ZnO nanowires and their application in field-effect transistors.” 2018. Doctoral Dissertation, Victoria University of Wellington. Accessed December 13, 2018.
http://hdl.handle.net/10063/6927.
MLA Handbook (7th Edition):
Burke-Govey, Conor Patrick. “ZnO nanowires and their application in field-effect transistors.” 2018. Web. 13 Dec 2018.
Vancouver:
Burke-Govey CP. ZnO nanowires and their application in field-effect transistors. [Internet] [Doctoral dissertation]. Victoria University of Wellington; 2018. [cited 2018 Dec 13].
Available from: http://hdl.handle.net/10063/6927.
Council of Science Editors:
Burke-Govey CP. ZnO nanowires and their application in field-effect transistors. [Doctoral Dissertation]. Victoria University of Wellington; 2018. Available from: http://hdl.handle.net/10063/6927
Arizona State University
10.
Joun, Hee-Joung.
Studies of Epitaxial Silicon Nanowire Growth at Low
Temperature.
Degree: PhD, Materials Science and Engineering, 2011, Arizona State University
URL: http://repository.asu.edu/items/9327
► Silicon nanowires were grown epitaxially on Si (100) and (111) surfaces using the Vapor-Liquid-Solid (VLS) mechanism under both thermal and plasma enhanced growth conditions. Nanowire…
(more)
▼ Silicon nanowires were grown epitaxially on Si (100)
and (111) surfaces using the Vapor-Liquid-Solid (VLS) mechanism
under both thermal and plasma enhanced growth conditions. Nanowire
morphology was investigated as a function of temperature, time,
disilane partial pressure and substrate preparation. Silicon
nanowires synthesized in low temperature plasma typically curved
compared to the linear nanowires grown under simple thermal
conditions. The nanowires tended bend more with increasing disilane
partial gas pressure up to 25 x10-3 mTorr. The nanowire curvature
measured geometrically is correlated with the shift of the main
silicon peak obtained in Raman spectroscopy. A mechanistic
hypothesis was proposed to explain the bending during plasma
activated growth. Additional driving forces related to
electrostatic and Van der Waals forces were also discussed. Deduced
from a systematic variation of a three-step experimental protocol,
the mechanism for bending was associated with asymmetric deposition
rate along the outer and inner wall of nanowire. The conditions
leading to nanowire branching were also examined using a two-step
growth process. Branching morphologies were examined as a function
of plasma powers between 1.5 W and 3.5 W. Post-annealing thermal
and plasma-assisted treatments in hydrogen were compared to
understand the influences in the absence of an external silicon
source (otherwise supplied by disilane). Longer and thicker
nanowires were associated with longer annealing times due to an
Ostwald-like ripening effect. The roles of surface diffusion, gas
diffusion, etching and deposition rates were
examined.
Subjects/Keywords: Materials Science; Bending nanowire; Branch nanowire; Nanocrystalline; PECVD; Si nanowire
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APA (6th Edition):
Joun, H. (2011). Studies of Epitaxial Silicon Nanowire Growth at Low
Temperature. (Doctoral Dissertation). Arizona State University. Retrieved from http://repository.asu.edu/items/9327
Chicago Manual of Style (16th Edition):
Joun, Hee-Joung. “Studies of Epitaxial Silicon Nanowire Growth at Low
Temperature.” 2011. Doctoral Dissertation, Arizona State University. Accessed December 13, 2018.
http://repository.asu.edu/items/9327.
MLA Handbook (7th Edition):
Joun, Hee-Joung. “Studies of Epitaxial Silicon Nanowire Growth at Low
Temperature.” 2011. Web. 13 Dec 2018.
Vancouver:
Joun H. Studies of Epitaxial Silicon Nanowire Growth at Low
Temperature. [Internet] [Doctoral dissertation]. Arizona State University; 2011. [cited 2018 Dec 13].
Available from: http://repository.asu.edu/items/9327.
Council of Science Editors:
Joun H. Studies of Epitaxial Silicon Nanowire Growth at Low
Temperature. [Doctoral Dissertation]. Arizona State University; 2011. Available from: http://repository.asu.edu/items/9327
Penn State University
11.
Cooley, Benjamin Joseph.
Growth, Structure, and Optical Characterization of Diluted
Magnetic Semiconductor Nanowires.
Degree: PhD, Physics, 2010, Penn State University
URL: https://etda.libraries.psu.edu/catalog/11303
► Nanowires combining the usually disparate areas of semiconductors and magnetism are of contemporary relevance within the context of semiconductor spintronics. This is a relatively new…
(more)
▼ Nanowires
combining the usually disparate areas of semiconductors and
magnetism are of contemporary relevance within the context of
semiconductor spintronics. This is a relatively new field of
research that seeks to exploit electron spin within electronic and
opto-electronic semiconductor devices. While much of the effort
within semiconductor spintronics has been directed toward
fundamental studies and applications of 3D, 2D and 0D systems,
there has been little work to date on 1D systems. The distinctive
change in the electronic density of states with changing
dimensionality provides a strong motivation for developing and
exploring semiconductor nanowires in which one might be able to
probe and control spin-dependent phenomena within a 1D or quasi-1D
environment. This thesis explores the crystal growth, structural
properties and magneto-optical behavior of quasi-1D semiconductor
nanowires in which we incorporate magnetism through two approaches:
first, by synthesizing nanowires of the diluted magnetic
semiconductor (Zn,Mn)Se, wherein the <i>d</i>-shell
electrons of substitutional Mn ions interact with the band states
of the ZnSe host lattice via <i>sp–d</i>
exchange; second, by making hybrid core-shell nanostructures
wherein a metallic ferromagnetic shell (MnAs) is epitaxially
deposited on a semiconductor nanowire (GaAs). After an introductory
overview of past work in the field and a description of the
experimental techniques relevant to the thesis, we discuss our
experimental results.
The first set of
experiments focuses on ZnSe and (Zn,Mn)Se nanowires grown in a
single stage. The nanowires were grown on Si and GaAs substrates
with a thin layer of gold evaporated onto them, which were then
annealed before growth so that the gold formed nanoscale droplets.
The growth yields samples covered in random arrays of nanowires
growing out an an angle to the substrate, with an undergrowth of
crooked nanowires and other small structures. The long thin
nanowires vary in diameter, down to ~ 10 nm, with ~ 15–20
nm being fairly common. Structural characterization done by
transmission electron microscopy (TEM) shows that the long
nanowires are largely single crystal, though often with many
stacking faults, and tend to form in the wurtzite crystal structure
with <i>c</i>-axis growth direction. Elemental analysis
performed on individual nanowires using X-ray energy dispersive
spectroscopy shows that Mn can be incorporated into
Zn<sub>1−<i>x</i></sub>Mn<sub><i>x</i></sub>Se
nanowires in high concentrations, up to <i>x</i> ~ 0.6.
Magneto-photoluminescence (magneto-PL) measurements of as-grown
samples reveal substantial Zeeman shifts in the near band edge
luminescence, but only partial polarization, indicating the
luminescence is originating in a nanostructured environment.
Surprisingly, however, nearly all of the PL signal comes from the
nanostructured undergrowth rather than the long nanowires, as shown
from magneto-PL measurements of samples which were sonicated…
Subjects/Keywords: diluted magnetic semiconductor; nanowire; semiconductor
nanowire; nanowire growth
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APA ·
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CSE |
Export
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APA (6th Edition):
Cooley, B. J. (2010). Growth, Structure, and Optical Characterization of Diluted
Magnetic Semiconductor Nanowires. (Doctoral Dissertation). Penn State University. Retrieved from https://etda.libraries.psu.edu/catalog/11303
Chicago Manual of Style (16th Edition):
Cooley, Benjamin Joseph. “Growth, Structure, and Optical Characterization of Diluted
Magnetic Semiconductor Nanowires.” 2010. Doctoral Dissertation, Penn State University. Accessed December 13, 2018.
https://etda.libraries.psu.edu/catalog/11303.
MLA Handbook (7th Edition):
Cooley, Benjamin Joseph. “Growth, Structure, and Optical Characterization of Diluted
Magnetic Semiconductor Nanowires.” 2010. Web. 13 Dec 2018.
Vancouver:
Cooley BJ. Growth, Structure, and Optical Characterization of Diluted
Magnetic Semiconductor Nanowires. [Internet] [Doctoral dissertation]. Penn State University; 2010. [cited 2018 Dec 13].
Available from: https://etda.libraries.psu.edu/catalog/11303.
Council of Science Editors:
Cooley BJ. Growth, Structure, and Optical Characterization of Diluted
Magnetic Semiconductor Nanowires. [Doctoral Dissertation]. Penn State University; 2010. Available from: https://etda.libraries.psu.edu/catalog/11303
University of Texas – Austin
12.
Smith, Damon Allen.
Mechanical, electromechanical, and optical properties of germanium nanowires.
Degree: Materials Science and Engineering, 2009, University of Texas – Austin
URL: http://hdl.handle.net/2152/7678
► In order to completely assess the potential of semiconductor nanowires for multifunctional applications such as flexible electronics, nanoelectromechanical systems (NEMS), and composites, a full characterization…
(more)
▼ In order to completely assess the potential of semiconductor nanowires for multifunctional applications such as flexible electronics, nanoelectromechanical systems (NEMS), and composites, a full characterization of their properties must be obtained. While many of their physical properties have been well studied, explorations of mechanical, electromechanical, and optical properties of semiconductor nanowires remain relatively sparse in the literature. Two major hurdles to the elucidation of these properties are: (1) the development of experimental techniques which are capable of mechanical and electromechanical measurements coupled with detailed structural analysis, and (2) the synthesis of high quality nanowires with the high yields necessary to produce the quantities needed for composite fabrication. These issues are addressed in this dissertation by utilizing the supercritical fluid-liquid-solid (SFLS) synthesis method to produce germanium (Ge)
nanowire specimens for mechanical and electromechanical measurements coupled with high-resolution transmission electron microscopy (HRTEM). In addition, excellent dispersibility and large quantities allow for optical measurements of dispersions and composites. Ge cantilever nanoelectromechanical resonators were fabricated and induced into resonance. From the frequency response, the Young's modulus of the nanowires was determined to be insensitive to diameter and on par with the literature values for bulk Ge. The mechanical quality factors of the resonators were found to decrease with decreasing diameter. The data indicate that energy dissipation from the oscillating cantilevers occurs predominantly via surface losses. The mechanical strengths of individual Ge nanowires were measured by in situ nanomanipulation in a scanning electron microscope (SEM). The nanowires were found to tolerate diameter-dependent flexural strains more than two orders of magnitude higher than bulk Ge. Corresponding bending strengths were in agreement with the ideal strength of a perfect Ge crystal, indicative of a reduced presence of extended defects. The nanowires also exhibited plastic deformation at room temperature, becoming amorphous at the point of maximum strain. The optical absorbance spectra of Ge nanowires were measured and found to exhibit spectra markedly different from bulk Ge. Simulations using a discrete dipole approximation (DDA) model suggest that the difference in light absorption results from light trapping within the nanowires.
Advisors/Committee Members: Korgel, Brian Allan, 1969- (advisor).
Subjects/Keywords: Germanium nanowires; Nanowire mechanical properties; Nanowire electromechanical properties; Nanowire optical properties
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APA (6th Edition):
Smith, D. A. (2009). Mechanical, electromechanical, and optical properties of germanium nanowires. (Thesis). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/7678
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Smith, Damon Allen. “Mechanical, electromechanical, and optical properties of germanium nanowires.” 2009. Thesis, University of Texas – Austin. Accessed December 13, 2018.
http://hdl.handle.net/2152/7678.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Smith, Damon Allen. “Mechanical, electromechanical, and optical properties of germanium nanowires.” 2009. Web. 13 Dec 2018.
Vancouver:
Smith DA. Mechanical, electromechanical, and optical properties of germanium nanowires. [Internet] [Thesis]. University of Texas – Austin; 2009. [cited 2018 Dec 13].
Available from: http://hdl.handle.net/2152/7678.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Smith DA. Mechanical, electromechanical, and optical properties of germanium nanowires. [Thesis]. University of Texas – Austin; 2009. Available from: http://hdl.handle.net/2152/7678
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Harvard University
13.
Choe, Hwan Sung.
Modulated Nanowire Structures for Exploring New Nanoprocessor Architectures and Approaches to Biosensing.
Degree: PhD, Physics, 2013, Harvard University
URL: http://nrs.harvard.edu/urn-3:HUL.InstRepos:11158237
► For the last decade, semiconducting nanowires synthesized by bottom-up methods have opened up new opportunities, stimulated innovative scientific research, and led to applications in materials…
(more)
▼ For the last decade, semiconducting nanowires synthesized by bottom-up methods have opened up new opportunities, stimulated innovative scientific research, and led to applications in materials science, electronics, optics, and biology at the nanoscale. Notably, nanowire building blocks with precise control of size, structure, morphology, and even composition in one, two, and three dimensions can successfully demonstrate high-performance electrical characteristics of field-effect transistors (FETs) and highly sensitive, selective, label-free, real-time biosensors in the fields of nanoelectronics and nano-biosensing, respectively. This thesis has focused on the design, synthesis, assembly, fabrication and electrical characterization of nanowire heterostructures for a proof-of-concept nanoprocessor and morphology-modulated kinked nanowire molecular nanosensor.
Physics
Advisors/Committee Members: Lieber, Charles M. (advisor), Park, Hongkun (committee member), Cohen, Adam (committee member).
Subjects/Keywords: Nanotechnology; Electrical engineering; Nanoscience; biosensor; electrochemical sensor; nanowire circuit; nanowire synthesis; Semiconductor nanowire
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APA (6th Edition):
Choe, H. S. (2013). Modulated Nanowire Structures for Exploring New Nanoprocessor Architectures and Approaches to Biosensing. (Doctoral Dissertation). Harvard University. Retrieved from http://nrs.harvard.edu/urn-3:HUL.InstRepos:11158237
Chicago Manual of Style (16th Edition):
Choe, Hwan Sung. “Modulated Nanowire Structures for Exploring New Nanoprocessor Architectures and Approaches to Biosensing.” 2013. Doctoral Dissertation, Harvard University. Accessed December 13, 2018.
http://nrs.harvard.edu/urn-3:HUL.InstRepos:11158237.
MLA Handbook (7th Edition):
Choe, Hwan Sung. “Modulated Nanowire Structures for Exploring New Nanoprocessor Architectures and Approaches to Biosensing.” 2013. Web. 13 Dec 2018.
Vancouver:
Choe HS. Modulated Nanowire Structures for Exploring New Nanoprocessor Architectures and Approaches to Biosensing. [Internet] [Doctoral dissertation]. Harvard University; 2013. [cited 2018 Dec 13].
Available from: http://nrs.harvard.edu/urn-3:HUL.InstRepos:11158237.
Council of Science Editors:
Choe HS. Modulated Nanowire Structures for Exploring New Nanoprocessor Architectures and Approaches to Biosensing. [Doctoral Dissertation]. Harvard University; 2013. Available from: http://nrs.harvard.edu/urn-3:HUL.InstRepos:11158237
University of Cincinnati
14.
Kaveh Baghbadorani, Masoud.
Emission and Dynamics of Charge Carriers in Uncoated and
Organic/Metal Coated Semiconductor Nanowires.
Degree: PhD, Arts and Sciences: Physics, 2016, University of Cincinnati
URL: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1470754655
► In this dissertation, the dynamics of excitons in hybrid metal/organic/nanowire structures possessing nanometer thick deposited molecular and metal films on top of InP and GaAs…
(more)
▼ In this dissertation, the dynamics of excitons in
hybrid metal/organic/
nanowire structures possessing nanometer thick
deposited molecular and metal films on top of InP and GaAs
nanowire
(NW) surfaces were investigated. Optical characterizations were
carried out as a function of the semiconductor NW material, design,
NW size and the type and thickness of the organic material and
metal used. Hybrid organic and plasmonic semiconductor
nanowire
heterostructures were fabricated using organic molecular beam
deposition technique. I investigated the photon emission of
excitons in ~150 nm diameter polytype wurtzite/zincblende InP NWs
and the influence of a few ten nanometer thick organic and metal
films on the emission using intensity- and temperature-dependent
time-integrated and timeresolved (TR) photoluminescence (PL). The
plasmonic NWs were coated with an Aluminum quinoline (Alq3)
interlayer and magnesium–silver (Mg0.9:Ag0.1) top layer. In
addition, the nonlinear optical technique of heterodyne four-wave
mixing was used (in collaboration with Prof. Wolfgang Langbein,
University of Cardiff) to study incoherent and coherent carrier
relaxation processes on bare nanowires on a 100 femtosecond
time-scale. Alq3 covered NWs reveal a stronger emission and a
longer decay time of exciton transitions indicating surface state
passivation at the Alq3/NW interface. Alq3/Mg:Ag NWs reveal a
strong quenching of the exciton emission which is predominantly
attributed to Forster energy-transfer from excitons to plasmon
oscillations in the metal cluster film. Changing the Mg:Ag to gold
and the organic Alq3 spacer layer to PTCDA leads to a similar
behavior, but the PL quenching is strongly increased. The observed
behavior is attributed to a more continuous gold deposition leading
to an increased Forster energy transfer and to a metal induced
band-bending. I also investigated ensembles of bare and gold/Alq3
coated GaAs-AlGaAs-GaAs coreshell NWs of 130 nm diameter. Plasmonic
NWs with Au coating reveal a significant reduction of the PL
intensity compared with the uncoated NWs. Organic-plasmonic NWs
with an additional Alq3 interlayer show a noticeably stronger PL
intensity which increases with rising Alq3 spacer thickness. Metal
induced band bending is mainly attributed to be responsible for the
PL quenching. TR PL measurements support our interpretation by
showing an increase in the exciton decay times as we increase the
spacer thickness. Au coated NWs also reveal a strong polarization
dependent absorption which is mainly due to the significant
dielectric mismatch between the nanowires and the adjacent vacuum
environment. Finally, the amplified spontaneous emission (ASE) and
possible plasmonic NW lasing from hybrid plasmonic core-shell GaAs
NW heterostructures was investigated. The plasmonic
heterostructures are composed of either bare NWs on an Au coated
glass substrate or Au coated NWs on a bare glass substrate.
Intensity-dependent PL on plasmonic NW samples reveals a
superlinear increase of the PL intensities which is attributed to
an ASE at a…
Advisors/Committee Members: Wagner, Hans Peter (Committee Chair).
Subjects/Keywords: Physics; InP Nanowire; GaAs Nanowire; Optical Characterization; Organic Plasmonic Heterostructures; HFWM; Plasmonic Nanowire Lasing
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APA (6th Edition):
Kaveh Baghbadorani, M. (2016). Emission and Dynamics of Charge Carriers in Uncoated and
Organic/Metal Coated Semiconductor Nanowires. (Doctoral Dissertation). University of Cincinnati. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=ucin1470754655
Chicago Manual of Style (16th Edition):
Kaveh Baghbadorani, Masoud. “Emission and Dynamics of Charge Carriers in Uncoated and
Organic/Metal Coated Semiconductor Nanowires.” 2016. Doctoral Dissertation, University of Cincinnati. Accessed December 13, 2018.
http://rave.ohiolink.edu/etdc/view?acc_num=ucin1470754655.
MLA Handbook (7th Edition):
Kaveh Baghbadorani, Masoud. “Emission and Dynamics of Charge Carriers in Uncoated and
Organic/Metal Coated Semiconductor Nanowires.” 2016. Web. 13 Dec 2018.
Vancouver:
Kaveh Baghbadorani M. Emission and Dynamics of Charge Carriers in Uncoated and
Organic/Metal Coated Semiconductor Nanowires. [Internet] [Doctoral dissertation]. University of Cincinnati; 2016. [cited 2018 Dec 13].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1470754655.
Council of Science Editors:
Kaveh Baghbadorani M. Emission and Dynamics of Charge Carriers in Uncoated and
Organic/Metal Coated Semiconductor Nanowires. [Doctoral Dissertation]. University of Cincinnati; 2016. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1470754655
University of Texas – Austin
15.
Hong, Ki-Pyo, M.S. in Engineering.
Rational fabrication, assembling and actuation of nanowire multi-mer nanomotors.
Degree: Mechanical Engineering, 2015, University of Texas – Austin
URL: http://hdl.handle.net/2152/46976
► Direct field induced manipulations of nanowires have been recognized as a possible alternative to conventional chemical based assembling techniques. In particular, manipulation of nanowires with…
(more)
▼ Direct field induced manipulations of nanowires have been recognized as a possible alternative to conventional chemical based assembling techniques. In particular, manipulation of nanowires with an external electric field allows the facile and precision assembly of nanowires into various nanoscale devices. In this study, we have rationally synthesized multisegment Au/Ni nanowires and assembled them into a unique type of rotary nanomotors made of
nanowire multi-mers with designed geometric configurations by the electric tweezers. The electric tweezers are a recent invention developed by Prof. Fan’s group, which are based on the combined electrophoretic and dielectrophoretic forces to transport and align nanowires independently in low Reynolds number suspensions. The Au/Ni multi-segmented nanowires are rationally designed and fabricated by electrodeposition into nanoporous templates. By employing the ferromagnetic properties of the nickel segments in the nanowires, we precisely transported and assembled randomly disperse nanowires into multi-mer
nanowire devices with designed configuration and further assembled them as the rotors of nanomotors. The magnetic attraction between the Ni segments in the nanowires holds the joints of dimers, trimers and tetramers tightly. The rotary nanomotors made of multiple assembled nanowires with designed configuration are the first to the best of our knowledge. Our study of their rotation behaviors as functions of voltage and frequency shows that the rotational speed of the nanomotors linearly increases with the square of the applied AC voltages and depends on the AC frequencies. The voltage square dependence is highly desirable for achieving ultrahigh speed rotation. This research could generate interest and impact multiple research fields including nanoelectromechanical system (NEMS) devices, nanomotors, microfluidic architectures and single-cell biology.
Advisors/Committee Members: Fan, Donglei (advisor), Li, Wei (committee member).
Subjects/Keywords: Nanomotor; Nanowire; Nanorotor; Nano-assembly; Nanowire multi-mers; Nanowire assembly; Rotary nanomotors
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APA (6th Edition):
Hong, Ki-Pyo, M. S. i. E. (2015). Rational fabrication, assembling and actuation of nanowire multi-mer nanomotors. (Thesis). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/46976
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Hong, Ki-Pyo, M S in Engineering. “Rational fabrication, assembling and actuation of nanowire multi-mer nanomotors.” 2015. Thesis, University of Texas – Austin. Accessed December 13, 2018.
http://hdl.handle.net/2152/46976.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Hong, Ki-Pyo, M S in Engineering. “Rational fabrication, assembling and actuation of nanowire multi-mer nanomotors.” 2015. Web. 13 Dec 2018.
Vancouver:
Hong, Ki-Pyo MSiE. Rational fabrication, assembling and actuation of nanowire multi-mer nanomotors. [Internet] [Thesis]. University of Texas – Austin; 2015. [cited 2018 Dec 13].
Available from: http://hdl.handle.net/2152/46976.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Hong, Ki-Pyo MSiE. Rational fabrication, assembling and actuation of nanowire multi-mer nanomotors. [Thesis]. University of Texas – Austin; 2015. Available from: http://hdl.handle.net/2152/46976
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Texas A&M University
16.
Gwak, Yunki.
Thermal Transport Measurement of Silicon-Germanium Nanowires.
Degree: 2010, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-889
► Thermal properties of one dimensional nanostructures are of interest for thermoelectric energy conversion. Thermoelectric efficiency is related to non dimensional thermoelectric figure of merit, ZT=S2…
(more)
▼ Thermal properties of one dimensional nanostructures are of interest for
thermoelectric energy conversion. Thermoelectric efficiency is related to non dimensional
thermoelectric figure of merit, ZT=S
2 o T/k, where S ,o , k and T are Seebeck
coefficient, electrical conductivity, thermal conductivity and the absolute temperature
respectively. These physical properties are interdependent. Therefore, making materials
with high ZT is a very challenging task. However, nanoscale materials can overcome some
of these limitations. When the size of nanomaterials is comparable to wavelength and mean
free path of energy carriers, especially phonons, size effect contributes to the thermal
conductivity reduction without bringing about major changes in the electrical conductivity
and the Seebeck coefficient. Therefore, the figure of merit ZT can be manipulated. For
example, the thermal conductivities of several silicon nanowires were more than two orders
of magnitude lower than that of bulk silicon values due to the enhanced boundary scattering.
Among the nanoscale semiconductor materials, Silicon-Germanium(SiGe) alloy
nanowire is a promising candidate for thermoelectric materials The thermal conductivities
of SiGe core-shell nanowires with core diameters of 96nm, 129nm and 177nm were
measured using a batch fabricated micro device in a temperature range of 40K-450K. SiGe nanowires used in the experiment were synthesized via the Vapour-Liquid-Solid (VLS)
growth method. The thermal conductivity data was compared with thermal conductivity of
Si and Ge nanowires. The data was compared with SiGe alloy thin film, bulk SiGe,
Si/SixGe1-x superlattice
nanowire, Si/Si0.7Ge0.3 superlattice thin film and also with the
thermal conductivity of Si0.5Ge0.5 calculated using the Einstein model. The thermal
conductivities of these SiGe alloy nanowires observed in this work are ~20 times lower
than Si nanowires, ~10 times lower than Ge nanowires, ~3-4 times lower than Si/SixGe1-x
superlattice thin film, Si/SixGe1-x superlattice
nanowire and about 3 time lower than bulk
SiGe alloy. The low values of thermal conductivity are majorly due to the effect of alloy
scattering, due to increased boundary scattering as a result of nanoscale diameters, and the
interface diffuse scattering by core-shell effect. The influence of core-shell effect, alloy
scattering and boundary scattering effect in reducing the thermal conductivity of these
nanowires opens up opportunities for tuning thermoelectric properties which can pave way
to thermoelectric materials with high figures of merit in the future.
Advisors/Committee Members: Yu, Choongho (advisor), Jin, Yongmei (committee member), Karaman, Ibrahim (committee member).
Subjects/Keywords: SiGe; nanowire; thermal conductivity
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APA (6th Edition):
Gwak, Y. (2010). Thermal Transport Measurement of Silicon-Germanium Nanowires. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-889
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Gwak, Yunki. “Thermal Transport Measurement of Silicon-Germanium Nanowires.” 2010. Thesis, Texas A&M University. Accessed December 13, 2018.
http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-889.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Gwak, Yunki. “Thermal Transport Measurement of Silicon-Germanium Nanowires.” 2010. Web. 13 Dec 2018.
Vancouver:
Gwak Y. Thermal Transport Measurement of Silicon-Germanium Nanowires. [Internet] [Thesis]. Texas A&M University; 2010. [cited 2018 Dec 13].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-889.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Gwak Y. Thermal Transport Measurement of Silicon-Germanium Nanowires. [Thesis]. Texas A&M University; 2010. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-889
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Osaka University / 大阪大学
17.
Asano, Atsushi; 麻野, 敦資.
Studies on 1-Dimensional Polymer Nanostructures with Functional Surfaces Prepared by Single Particle Nano-Fabrication Technique : 一次元高分子ナノ構造体の単一粒子反応を利用した形成と機能化に関する研究; イチジゲン コウブンシ ナノ コウゾウタイ ノ タンイツ リュウシ ハンオウ ヲ リヨウ シタ ケイセイ ト キノウカ 二 カンスル ケンキュウ.
Degree: 博士（工学）, 2013, Osaka University / 大阪大学
URL: http://hdl.handle.net/11094/27555
14401甲第16371号
博士（工学）
大阪大学
2013-03-25
26157
Subjects/Keywords: polystyrene; nanowire
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APA (6th Edition):
Asano, Atsushi; 麻野, . (2013). Studies on 1-Dimensional Polymer Nanostructures with Functional Surfaces Prepared by Single Particle Nano-Fabrication Technique : 一次元高分子ナノ構造体の単一粒子反応を利用した形成と機能化に関する研究; イチジゲン コウブンシ ナノ コウゾウタイ ノ タンイツ リュウシ ハンオウ ヲ リヨウ シタ ケイセイ ト キノウカ 二 カンスル ケンキュウ. (Thesis). Osaka University / 大阪大学. Retrieved from http://hdl.handle.net/11094/27555
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Asano, Atsushi; 麻野, 敦資. “Studies on 1-Dimensional Polymer Nanostructures with Functional Surfaces Prepared by Single Particle Nano-Fabrication Technique : 一次元高分子ナノ構造体の単一粒子反応を利用した形成と機能化に関する研究; イチジゲン コウブンシ ナノ コウゾウタイ ノ タンイツ リュウシ ハンオウ ヲ リヨウ シタ ケイセイ ト キノウカ 二 カンスル ケンキュウ.” 2013. Thesis, Osaka University / 大阪大学. Accessed December 13, 2018.
http://hdl.handle.net/11094/27555.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Asano, Atsushi; 麻野, 敦資. “Studies on 1-Dimensional Polymer Nanostructures with Functional Surfaces Prepared by Single Particle Nano-Fabrication Technique : 一次元高分子ナノ構造体の単一粒子反応を利用した形成と機能化に関する研究; イチジゲン コウブンシ ナノ コウゾウタイ ノ タンイツ リュウシ ハンオウ ヲ リヨウ シタ ケイセイ ト キノウカ 二 カンスル ケンキュウ.” 2013. Web. 13 Dec 2018.
Vancouver:
Asano, Atsushi; 麻野 . Studies on 1-Dimensional Polymer Nanostructures with Functional Surfaces Prepared by Single Particle Nano-Fabrication Technique : 一次元高分子ナノ構造体の単一粒子反応を利用した形成と機能化に関する研究; イチジゲン コウブンシ ナノ コウゾウタイ ノ タンイツ リュウシ ハンオウ ヲ リヨウ シタ ケイセイ ト キノウカ 二 カンスル ケンキュウ. [Internet] [Thesis]. Osaka University / 大阪大学; 2013. [cited 2018 Dec 13].
Available from: http://hdl.handle.net/11094/27555.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Asano, Atsushi; 麻野 . Studies on 1-Dimensional Polymer Nanostructures with Functional Surfaces Prepared by Single Particle Nano-Fabrication Technique : 一次元高分子ナノ構造体の単一粒子反応を利用した形成と機能化に関する研究; イチジゲン コウブンシ ナノ コウゾウタイ ノ タンイツ リュウシ ハンオウ ヲ リヨウ シタ ケイセイ ト キノウカ 二 カンスル ケンキュウ. [Thesis]. Osaka University / 大阪大学; 2013. Available from: http://hdl.handle.net/11094/27555
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Addis Ababa University
18.
Kidist, Moges.
MODELING OF SILICON NANOWIRE FIELD EFFECT TRANSISTORS
.
Degree: 2013, Addis Ababa University
URL: http://etd.aau.edu.et/dspace/handle/123456789/4501
► Modeling and simulation of Metal Oxide Semiconductor Field Effect Transistors (MOSFETs) is very essential in order to understand the device physics, electrostatics and other important…
(more)
▼ Modeling and simulation of Metal Oxide Semiconductor Field Effect Transistors (MOSFETs) is
very essential in order to understand the device physics, electrostatics and other important
phenomena occurring in this device. Therefore, in this thesis the modeling and simulation of
Silicon Nano Wire field Effect Transistors (SiNW FETs) is done. The modeling is done assuming
both ballistic transport and transport in the presence of scattering. The modeling of SiNW FETs
assuming ballistic transport is an extension of the Natori’s theory of ballistic MOSFETs. The
second part of the modeling, which is developed on the assumption of scattering transport, is
based on McKelvey’s flux method. When the scattering effects are assumed to be absent, the
scattering model reduces to the ballistic model. Therefore, the main novelty introduced in this
thesis is the extension of the previous models and the incorporation of these two models together.
After the derivation of the model, its benchmarking is also done. This is accomplished by
comparing the simulation results of the developed model, which is implemented using MATLAB
programming, with that of the experimental and numerical simulation results. Various important
parameters are extracted and used for comparison, the main ones being the On-state current (Ion),
the Off-state current (Ioff), the Subthreshold Slope (SS) and drain induced barrier lowering
(DIBL). The comparison shows that there is a good agreement between the simulation results of
the developed model and the experimental and numerical simulation results, which indicates the
validity of the model. Finally, the effect of scaling of the physical parameters on the device
performance is investigated. The main parameters chosen for this investigation are the diameter
of the Nano Wire (NW) and the gate oxide thickness. When a simulation is done by varying these
parameters, Ion and Ioff currents are found to be affected greatly.
Advisors/Committee Members: Dr. Adeyabeba Abera (advisor).
Subjects/Keywords: SILICON NANOWIRE;
TRANSISTORS;
FIELD EFFECT
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APA (6th Edition):
Kidist, M. (2013). MODELING OF SILICON NANOWIRE FIELD EFFECT TRANSISTORS
. (Thesis). Addis Ababa University. Retrieved from http://etd.aau.edu.et/dspace/handle/123456789/4501
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Kidist, Moges. “MODELING OF SILICON NANOWIRE FIELD EFFECT TRANSISTORS
.” 2013. Thesis, Addis Ababa University. Accessed December 13, 2018.
http://etd.aau.edu.et/dspace/handle/123456789/4501.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Kidist, Moges. “MODELING OF SILICON NANOWIRE FIELD EFFECT TRANSISTORS
.” 2013. Web. 13 Dec 2018.
Vancouver:
Kidist M. MODELING OF SILICON NANOWIRE FIELD EFFECT TRANSISTORS
. [Internet] [Thesis]. Addis Ababa University; 2013. [cited 2018 Dec 13].
Available from: http://etd.aau.edu.et/dspace/handle/123456789/4501.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Kidist M. MODELING OF SILICON NANOWIRE FIELD EFFECT TRANSISTORS
. [Thesis]. Addis Ababa University; 2013. Available from: http://etd.aau.edu.et/dspace/handle/123456789/4501
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
The Ohio State University
19.
Lee, Huyong.
Titanium Oxide Nanowire Growth by Oxidation Under a Limited
Supply of Oxygen: Processing and Characterization.
Degree: PhD, Materials Science and Engineering, 2009, The Ohio State University
URL: http://rave.ohiolink.edu/etdc/view?acc_num=osu1236191211
► Instead of using expensive and complex methods to produce 1D structures, a simple direct oxidation method has been developed to produce either pure TiO2…
(more)
▼ Instead of using expensive and complex
methods to produce 1D structures, a simple direct oxidation method
has been developed to produce either pure
TiO
2 nanowire or heterogeneous nanowires
under a limited supply of oxygen. The dimension of the nanofibers
ranged from 30 to 60 nm in diameter and their length were between
500 nm to several µm depending on Ti alloy samples. Experimental
parameters such as flow rate, heat treatment temperature, and gas
constituent have effects on the surface morphology of the samples.
Based on studies under various conditions, pure
TiO
2 nanowires were only grown on pure Ti
samples at the heat treatment temperature of 600 °C with an Ar flow
rate of 200 ml/min. As the heat treatment temperature increased,
well faceted crystals were formed and connected to each other to
form a continuous oxide scale. As the flow rate increased, the
formation of nanowires were hindered and an oxide layer was formed
rather than the formation of nanowires. The phase of nanowires was
determined to be rutile based on SAED pattern from TEM
analyses. For Ti alloy samples, the growth of
nanowires was accelerated in terms of the density and length. The
effects of the heat treatment temperature on the surface morphology
were similar to those of pure Ti samples. However, the effect of
the flow rate was not prominent as those of pure Ti samples.
Consequently, the growth processing window for Ti alloys is larger
than that of pure Ti samples with respect to the flow rate. The
phase characterization of nanowires by XRD and TEM analyses
indicated that the inner rutile core was covered by an Al rich
outer layer. While the growth mechanism for
nanowire formation is not well understood, it is established that
the growth occurs at the tip and that the rate limiting step is the
transport of oxygen through the gas boundary layer. Additionally,
1D growth implies surface reaction anisotropy that disappears at
high temperature promoting oxide cale growth. the Based on
experimental observations, a four-stage mechanism is proposed as a
function of time. In stage I, a cracked oxide scale grows followed
by the formation of bumps in stage II that act as nucleation sites
for nanowires. In stage III, nanowires continue to grow along with
nucleation and growth of new nanowires leading to the increase in
density. In stage IV, the density of nanowires is so large that the
accessibility of oxygen to the base becomes difficult and nanowires
continue to grow at the tip.
Advisors/Committee Members: Akbar, Sheikh (Advisor), Dregia, Suliman (Advisor).
Subjects/Keywords: Materials Science; Nanowire; oxidation; TiO2
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APA (6th Edition):
Lee, H. (2009). Titanium Oxide Nanowire Growth by Oxidation Under a Limited
Supply of Oxygen: Processing and Characterization. (Doctoral Dissertation). The Ohio State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=osu1236191211
Chicago Manual of Style (16th Edition):
Lee, Huyong. “Titanium Oxide Nanowire Growth by Oxidation Under a Limited
Supply of Oxygen: Processing and Characterization.” 2009. Doctoral Dissertation, The Ohio State University. Accessed December 13, 2018.
http://rave.ohiolink.edu/etdc/view?acc_num=osu1236191211.
MLA Handbook (7th Edition):
Lee, Huyong. “Titanium Oxide Nanowire Growth by Oxidation Under a Limited
Supply of Oxygen: Processing and Characterization.” 2009. Web. 13 Dec 2018.
Vancouver:
Lee H. Titanium Oxide Nanowire Growth by Oxidation Under a Limited
Supply of Oxygen: Processing and Characterization. [Internet] [Doctoral dissertation]. The Ohio State University; 2009. [cited 2018 Dec 13].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1236191211.
Council of Science Editors:
Lee H. Titanium Oxide Nanowire Growth by Oxidation Under a Limited
Supply of Oxygen: Processing and Characterization. [Doctoral Dissertation]. The Ohio State University; 2009. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1236191211
University of Akron
20.
Kucherlapati, Naga Swathi.
Modeling of a Three Layer Coated Nanowire Transistor.
Degree: MSin Engineering, Electrical Engineering, 2010, University of Akron
URL: http://rave.ohiolink.edu/etdc/view?acc_num=akron1291935683
► The integration density of silicon transistors is increasing from the past few decades due to rapid miniaturization. Bipolar junction transistors (BJT) successfully replaced vacuum…
(more)
▼ The integration density of silicon
transistors is increasing from the past few decades due to rapid
miniaturization. Bipolar junction transistors (BJT) successfully
replaced vacuum tubes but the main problem using BJT's include
speed and current gain. To further improve integration density,
speed and current gain nanoscale transistors are being explored.
This thesis discusses the design of
nanowire transistor with 50nm
or less base width. It assumes that the device structure is
cylindrical in shape which is different from BJT. The method of
implementation in nanoscale is adopted from basic macroscale from a
classical paper by Rittner. Regardless of the
evolution, the theory behind the transistor dates back to 1947, by
the discovery of Shockley. Rittner's paper examines approximations
used in shockley's results and these examinations are used as
analysis tools in this work. This work is an extension to Rittner's
paper, it numerically solves the nonlinear equation for bipolar
junction transistor. It also derives
nanowire transistor linear and
nonlinear equations based on the mathematical formulations of
bipolar junction transistor. Solutions to
nanowire linear and
nonlinear equations are compared and justified in light of the
results from BJT.
Advisors/Committee Members: Hariharan, S. I. (Advisor).
Subjects/Keywords: Electrical Engineering; nanowire transistor
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APA (6th Edition):
Kucherlapati, N. S. (2010). Modeling of a Three Layer Coated Nanowire Transistor. (Masters Thesis). University of Akron. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=akron1291935683
Chicago Manual of Style (16th Edition):
Kucherlapati, Naga Swathi. “Modeling of a Three Layer Coated Nanowire Transistor.” 2010. Masters Thesis, University of Akron. Accessed December 13, 2018.
http://rave.ohiolink.edu/etdc/view?acc_num=akron1291935683.
MLA Handbook (7th Edition):
Kucherlapati, Naga Swathi. “Modeling of a Three Layer Coated Nanowire Transistor.” 2010. Web. 13 Dec 2018.
Vancouver:
Kucherlapati NS. Modeling of a Three Layer Coated Nanowire Transistor. [Internet] [Masters thesis]. University of Akron; 2010. [cited 2018 Dec 13].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=akron1291935683.
Council of Science Editors:
Kucherlapati NS. Modeling of a Three Layer Coated Nanowire Transistor. [Masters Thesis]. University of Akron; 2010. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=akron1291935683
University of Cincinnati
21.
Lai, Peng.
Mesoporous Silica Nanowires by Space-confined
Organic-Inorganic Hybrid Self-Assembly.
Degree: MS, Engineering : Materials Science, 2007, University of Cincinnati
URL: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1172113649
► This research focuses on the space-confined P123-silica hybrid self-assembly. Mesoporous silica nanowires with various diameters (10 – 400nm) were synthesized via sol-gel combined vapor-induced self-assembly…
(more)
▼ This research focuses on the space-confined
P123-silica hybrid self-assembly. Mesoporous silica nanowires with
various diameters (10 – 400nm) were synthesized via sol-gel
combined vapor-induced self-assembly in both AAO and EPC channels.
Scanning transmission electron Microscope (STEM) was used to
characterize the samples in terms of nanopore size, ordering, and
orientation. The mesoporous structure of silica wires formed in EPC
with diameter less than 400 nm are first reported. Substrate effect
(EPC vs AAO) and processing condition effect on the morphology of
the mesoporous structure of silica wires are present and discussed.
The more ordered and uniform mesoporous structure is preferentially
formed in narrower substrate channel confinement. A critical
diameter (dc) of hard template channels is around 30-50 nm, below
which the space confinement effect leads to more uniform
nanostructured nanowires; above the dc, mixed mesostrcucture
usually exist. The formation of various meso-structures of silica
wires is sensitive to process conditions.
Advisors/Committee Members: Shi, Dr. Donglu (Advisor).
Subjects/Keywords: nanowire; self-assembly; AAO; EPC
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APA ·
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MLA ·
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Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lai, P. (2007). Mesoporous Silica Nanowires by Space-confined
Organic-Inorganic Hybrid Self-Assembly. (Masters Thesis). University of Cincinnati. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=ucin1172113649
Chicago Manual of Style (16th Edition):
Lai, Peng. “Mesoporous Silica Nanowires by Space-confined
Organic-Inorganic Hybrid Self-Assembly.” 2007. Masters Thesis, University of Cincinnati. Accessed December 13, 2018.
http://rave.ohiolink.edu/etdc/view?acc_num=ucin1172113649.
MLA Handbook (7th Edition):
Lai, Peng. “Mesoporous Silica Nanowires by Space-confined
Organic-Inorganic Hybrid Self-Assembly.” 2007. Web. 13 Dec 2018.
Vancouver:
Lai P. Mesoporous Silica Nanowires by Space-confined
Organic-Inorganic Hybrid Self-Assembly. [Internet] [Masters thesis]. University of Cincinnati; 2007. [cited 2018 Dec 13].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1172113649.
Council of Science Editors:
Lai P. Mesoporous Silica Nanowires by Space-confined
Organic-Inorganic Hybrid Self-Assembly. [Masters Thesis]. University of Cincinnati; 2007. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1172113649
NSYSU
22.
Wang, Ching-Wen.
Synthesis of Silver Nanowires by TiO2 Nanoparticles.
Degree: Master, Chemistry, 2008, NSYSU
URL: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0623108-164201
► ãSilver nanowires prepared by the the reduction of AgNO3 at low temperature with thermocatalystic biphase (anatase and brookite phases) TiO2 nanoparticles are described. Furthermore, the…
(more)
▼ ãSilver nanowires prepared by the the reduction of AgNO3 at low temperature with thermocatalystic biphase (anatase and brookite phases) TiO2 nanoparticles are described. Furthermore, the possible mechanism to grow silver nanowires without the help of the Ag seed and capping reagent is proposed.
ãFirstly, the amorphous TiO2 nanoparticles prepared by sol-gel method were spin-coated on the silicon wafer to form amorphous TiO2 matrix. Then an aqueous AgNO3 (1 µL 0.7 M) solution was dropped on the amorphous TiO2 matrix. Following the heat treatment at 200 °C for 8 h, the silver nanowires (length~10 µm, line width~100 nm) were grown on the silicon wafer. We found that amorphous phase of TiO2 was changed to the anatase and brookite phases during the thermal reduction of the aqueous solution of AgNO3.
ãSilver nanowires were characterized as f.c.c. structure by XRD. The TiO2 particles play an important role in providing electrons and holes for redox reaction and nucleation. With the controlling of the heating temperature and the amount of AgNO3, the silver nanowires were selectively grown in one dimension with large energetic surface. A combination of HR-TEM imaging and selected area electron diffraction reveals that the growing direction for the Ag wires is <011>.
Advisors/Committee Members: Lan-Chang Liang (chair), Chin-Hsing Chou (chair), Teng-Yuan Dong (committee member), Nein-Chen Chang (chair).
Subjects/Keywords: nanoparticle; TiO2; silver nanowire
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APA (6th Edition):
Wang, C. (2008). Synthesis of Silver Nanowires by TiO2 Nanoparticles. (Thesis). NSYSU. Retrieved from http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0623108-164201
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Wang, Ching-Wen. “Synthesis of Silver Nanowires by TiO2 Nanoparticles.” 2008. Thesis, NSYSU. Accessed December 13, 2018.
http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0623108-164201.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Wang, Ching-Wen. “Synthesis of Silver Nanowires by TiO2 Nanoparticles.” 2008. Web. 13 Dec 2018.
Vancouver:
Wang C. Synthesis of Silver Nanowires by TiO2 Nanoparticles. [Internet] [Thesis]. NSYSU; 2008. [cited 2018 Dec 13].
Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0623108-164201.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Wang C. Synthesis of Silver Nanowires by TiO2 Nanoparticles. [Thesis]. NSYSU; 2008. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0623108-164201
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University College Cork
23.
Kelly, Róisín A.
Modifying germanium nanowires for future devices: an in situ TEM study.
Degree: 2016, University College Cork
URL: http://hdl.handle.net/10468/2752
► Germanium was of great interest in the 1950’s when it was used for the first transistor device. However, due to the water soluble and unstable…
(more)
▼ Germanium was of great interest in the 1950’s when it was used for the first transistor device. However, due to the water soluble and unstable oxide it was surpassed by silicon. Today, as device dimensions are shrinking the silicon oxide is no longer suitable due to gate leakage and other low-κ dielectrics such as Al2O3 and HfO2 are being used. Germanium (Ge) is a promising material to replace or integrate with silicon (Si) to continue the trend of Moore’s law. Germanium has better intrinsic mobilities than silicon and is also silicon fab compatible so it would be an ideal material choice to integrate into silicon-based technologies. The progression towards nanoelectronics requires a lot of in depth studies. Dynamic TEM studies allow observations of reactions to allow a better understanding of mechanisms and how an external stimulus may affect a material/structure. This thesis details in situ TEM experiments to investigate some essential processes for germanium
nanowire (NW) integration into nanoelectronic devices; i.e. doping and Ohmic contact formation. Chapter 1 reviews recent advances in dynamic TEM studies on semiconductor (namely silicon and germanium) nanostructures. The areas included are
nanowire/crystal growth, germanide/silicide formation, irradiation, electrical biasing, batteries and strain. Chapter 2 details the study of ion irradiation and the damage incurred in germanium nanowires. An experimental set-up is described to allow for concurrent observation in the TEM of a
nanowire following sequential ion implantation steps. Grown nanowires were deposited on a FIB labelled SiN membrane grid which facilitated HRTEM imaging and facile navigation to a specific
nanowire. Cross sections of irradiated nanowires were also performed to evaluate the damage across the
nanowire diameter. Experiments were conducted at 30 kV and 5 kV ion energies to study the effect of beam energy on nanowires of varied diameters. The results on nanowires were also compared to the damage profile in bulk germanium with both 30 kV and 5 kV ion beam energies. Chapter 3 extends the work from chapter 2 whereby nanowires are annealed post ion irradiation. In situ thermal annealing experiments were conducted to observe the recrystallization of the nanowires. A method to promote solid phase epitaxial growth is investigated by irradiating only small areas of a
nanowire to maintain a seed from which the epitaxial growth can initiate. It was also found that strain in the
nanowire greatly effects defect formation and random nucleation and growth. To obtain full recovery of the crystal structure of a
nanowire, a stable support which reduces strain in the
nanowire is essential as well as containing a seed from which solid phase epitaxial growth can initiate. Chapter 4 details the study of nickel germanide formation in germanium nanostructures. Rows of EBL (electron beam lithography) defined Ni-capped germanium nanopillars were extracted in FIB cross sections and annealed in situ to observe the germanide formation. Chapter 5 summarizes the key…
Advisors/Committee Members: Petkov, Nikolay, Holmes, Justin D., SFI.
Subjects/Keywords: Germanium; Nanowire; Irradiation; Recrystallisation; Germanide
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APA (6th Edition):
Kelly, R. A. (2016). Modifying germanium nanowires for future devices: an in situ TEM study. (Thesis). University College Cork. Retrieved from http://hdl.handle.net/10468/2752
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Kelly, Róisín A. “Modifying germanium nanowires for future devices: an in situ TEM study.” 2016. Thesis, University College Cork. Accessed December 13, 2018.
http://hdl.handle.net/10468/2752.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Kelly, Róisín A. “Modifying germanium nanowires for future devices: an in situ TEM study.” 2016. Web. 13 Dec 2018.
Vancouver:
Kelly RA. Modifying germanium nanowires for future devices: an in situ TEM study. [Internet] [Thesis]. University College Cork; 2016. [cited 2018 Dec 13].
Available from: http://hdl.handle.net/10468/2752.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Kelly RA. Modifying germanium nanowires for future devices: an in situ TEM study. [Thesis]. University College Cork; 2016. Available from: http://hdl.handle.net/10468/2752
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University College Cork
24.
Wahl, Amélie.
Fabrication, characterisation and electroanalysis at 1-dimensional nanostructures.
Degree: 2013, University College Cork
URL: http://hdl.handle.net/10468/1740
► Integrated nanowire electrodes that permit direct, sensitive and rapid electrochemical based detection of chemical and biological species are a powerful emerging class of sensor devices.…
(more)
▼ Integrated
nanowire electrodes that permit direct, sensitive and rapid electrochemical based detection of chemical and biological species are a powerful emerging class of sensor devices. As critical dimensions of the electrodes enter the nanoscale, radial analyte diffusion profiles to the electrode dominate with a corresponding enhancement in mass transport, steady-state sigmoidal voltammograms, low depletion of target molecules and faster analysis. To optimise these sensors it is necessary to fully understand the factors that influence performance limits including: electrode geometry, electrode dimensions, electrode separation distances (within
nanowire arrays) and diffusional mass transport. Therefore, in this thesis, theoretical simulations of analyte diffusion occurring at a variety of electrode designs were undertaken using Comsol Multiphysics®. Sensor devices were fabricated and corresponding experiments were performed to challenge simulation results. Two approaches for the fabrication and integration of metal
nanowire electrodes are presented: Template Electrodeposition and Electron-Beam Lithography. These approaches allow for the fabrication of nanowires which may be subsequently integrated at silicon chip substrates to form fully functional electrochemical devices. Simulated and experimental results were found to be in excellent agreement validating the simulation model. The electrochemical characteristics exhibited by
nanowire electrodes fabricated by electronbeam lithography were directly compared against electrochemical performance of a commercial ultra-microdisc electrode. Steady-state cyclic voltammograms in ferrocenemonocarboxylic acid at single ultra-microdisc electrodes were observed at low to medium scan rates (≤ 500 mV.s-1). At nanowires, steady-state responses were observed at ultra-high scan rates (up to 50,000 mV.s-1), thus allowing for much faster analysis (20 ms). Approaches for elucidating faradaic signal without the requirement for background subtraction were also developed. Furthermore, diffusional process occurring at arrays with increasing inter-electrode distance and increasing number of nanowires were explored. Diffusion profiles existing at
nanowire arrays were simulated with Comsol Multiphysics®. A range of scan rates were modelled, and experiments were undertaken at 5,000 mV.s-1 since this allows rapid data capture required for, e.g., biomedical, environmental and pharmaceutical diagnostic applications.
Advisors/Committee Members: O'Riordan, Alan.
Subjects/Keywords: Nanotechnology; Nanowire electrodes; Electrochemistry; Electroanalysis
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APA (6th Edition):
Wahl, A. (2013). Fabrication, characterisation and electroanalysis at 1-dimensional nanostructures. (Thesis). University College Cork. Retrieved from http://hdl.handle.net/10468/1740
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Wahl, Amélie. “Fabrication, characterisation and electroanalysis at 1-dimensional nanostructures.” 2013. Thesis, University College Cork. Accessed December 13, 2018.
http://hdl.handle.net/10468/1740.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Wahl, Amélie. “Fabrication, characterisation and electroanalysis at 1-dimensional nanostructures.” 2013. Web. 13 Dec 2018.
Vancouver:
Wahl A. Fabrication, characterisation and electroanalysis at 1-dimensional nanostructures. [Internet] [Thesis]. University College Cork; 2013. [cited 2018 Dec 13].
Available from: http://hdl.handle.net/10468/1740.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Wahl A. Fabrication, characterisation and electroanalysis at 1-dimensional nanostructures. [Thesis]. University College Cork; 2013. Available from: http://hdl.handle.net/10468/1740
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Penn State University
25.
Krishnasamy Bharathi, Arvind.
ANALYSIS OF THE THERMAL PROPERTIES OF.
Degree: MS, Mechanical Engineering, 2010, Penn State University
URL: https://etda.libraries.psu.edu/catalog/11497
► The objective of this paper is to determine the thermal conductivity of Zinc Oxide nanowire by equilibrium and non-equilibrium molecular dynamics (EMD and NEMD) simulations…
(more)
▼ The objective of this paper is to determine the
thermal conductivity of Zinc Oxide nanowire by equilibrium and
non-equilibrium molecular dynamics (EMD and NEMD) simulations using
the ReaxFF reactive force field [19]. While EMD uses an
equilibrated system and statistical averaging; NEMD uses
cooling/heating rates in order to calculate the conductivity. The
validity of the methods is first verified using Argon as a test
case. The thermal conductivity of Argon thus calculated is compared
with the results obtained by Bhowmick and Shenoy [69]. We then
study the effects of system size using EMD method and effects of
periodic boundary conditions - 1D, 2D and bulk variation of
conductivity with temperature are analyzed using NEMD simulations.
The results obtained compare favorably with those measured
experimentally [46][47]. This indicates that the EMD and NEMD
methods are reliable alternatives to the traditional Green-Kubo
approach [51]; which is traditionally employed in MD-based thermal
conductivity determination. In conjunction with ReaxFF, these
methods are computationally cheaper than the Green-Kubo method and
can be used to determine the thermal conductivity of materials
involved in surface chemistry reactions such as catalysis and
sintering. The effect of chemistry on the thermal conductivity of
Zinc Oxide is studied. Sintering is taken as the chemical process
of interest and is simulated using ReaxFF force field for Zinc
Oxide [58] in the presence of water. Effect of sintering
temperature is also observed. A clear drop in the conductivity of
Zinc Oxide due to the formation of hydroxyl grain-boundaries
between the different Zinc Oxide clusters is noted. However, this
deterioration is smaller when we use higher sintering temperatures.
Due to a relatively small number of atoms (960) and the
non-homogeneousness of the cluster; (mix of Zinc Oxide and water)
the error bars on thermal conductivity are large. This indicates
the need for performing larger-scale simulations in order to
determine the effect of sintering on thermal-conductivity more
accurately.
Subjects/Keywords: nanowire; Zinc Oxide; ReaxFF
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APA (6th Edition):
Krishnasamy Bharathi, A. (2010). ANALYSIS OF THE THERMAL PROPERTIES OF. (Masters Thesis). Penn State University. Retrieved from https://etda.libraries.psu.edu/catalog/11497
Chicago Manual of Style (16th Edition):
Krishnasamy Bharathi, Arvind. “ANALYSIS OF THE THERMAL PROPERTIES OF.” 2010. Masters Thesis, Penn State University. Accessed December 13, 2018.
https://etda.libraries.psu.edu/catalog/11497.
MLA Handbook (7th Edition):
Krishnasamy Bharathi, Arvind. “ANALYSIS OF THE THERMAL PROPERTIES OF.” 2010. Web. 13 Dec 2018.
Vancouver:
Krishnasamy Bharathi A. ANALYSIS OF THE THERMAL PROPERTIES OF. [Internet] [Masters thesis]. Penn State University; 2010. [cited 2018 Dec 13].
Available from: https://etda.libraries.psu.edu/catalog/11497.
Council of Science Editors:
Krishnasamy Bharathi A. ANALYSIS OF THE THERMAL PROPERTIES OF. [Masters Thesis]. Penn State University; 2010. Available from: https://etda.libraries.psu.edu/catalog/11497
Penn State University
26.
Pan, Suxing.
A Novel Approach For Fabricating Nanochannel Templates For
Si Nanowire Growth And Transistor Fabrication.
Degree: PhD, Engineering Science and Mechanics, 2013, Penn State University
URL: https://etda.libraries.psu.edu/catalog/18933
► For the past decades, silicon nanowire (SiNW) has been extensively studied due to their unique electric, optical, and mechanical properties and great compatibility with modern…
(more)
▼ For the past decades, silicon nanowire (SiNW) has been
extensively studied due to their unique electric, optical, and
mechanical properties and great compatibility with modern
integrated circuits industry. Researchers have successfully
demonstrated its potential applications in many fields, such as
high performance transistors, high resolution and sensitivity bio
and chemical sensors and so on. Scientists even predicted it is
most likely that SiNW transistor will become the final winner for
the competition of future generation transistor architecture.
Therefore, it is very obvious that SiNW has become the rising star
for future nanoelectronics. Up to date, many efforts have been
devoted to synthesizing SiNW. In general, there are two main
categories in terms of SiNW growth methods, and post growth device
fabrication and assembly: “grow-and-place” and “grow-in-place”. For
“grow-and-place” approach, intensive post growth treatments are
needed to fully realize SiNW device application, which leads to
higher cost and lower throughput. For “grow-in-place” approach, the
SiNW is grown on the substrate, where the final device will be
fabricated, and there is no post growth treatments needed. This
approach improves the throughput and cost of “grow-in-place”
approach. However, it is still a great challenge for realizing mass
production of SiNW based device due to the lack of well-controlled
nanofabrication techniques with lower cost and higher throughput.
To resolve some of these above-mentioned issues, in this thesis, we
have developed a novel approach for fabricating nanochannel
templates for SiNW growth and further device applications. This
method represents “grow-in-place” approach and takes full
advantages of “grow-in-place” approaches. However, it has several
improvements compared with “grow-in-place” approach in terms of the
fabrication of nanochannel templates, and catalyst patterning and
control. We have investigated two alternative sacrificial materials
for nanochannel templates, which are further used for encapsulated
SiNW growth. Those two alternative sacrificial materials are
polymers of specified properties and amorphous silicon.
Specifically, we have explored the NXR 3022 polymer, which is water
soluble, and NXR 1025 polymer, which is general solvent soluble. In
addition, we have investigated and optimized the patterning
techniques of sacrificial polymer based on the throughput,
patterning cost and polymer compatibility with subsequent process
steps. Taking into account of all the factors, we have chosen new
nanoimprinting lithography to pattern the polymers. Detailed
procedures and issues encountered during the nanochannel
fabrication process will be discussed. For inorganic amorphous
silicon, we have successfully demonstrated its capability as the
sacrificial material of nanochannel. The advantages of using
amorphous silicon are as follows: process simplicity, great
compatibility with further processes as well as its ease of dry
removal for forming nanochannels. Through this novel proposed
approach, we have…
Subjects/Keywords: Silicon Nanowire; Transistor; AMOSFET
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APA (6th Edition):
Pan, S. (2013). A Novel Approach For Fabricating Nanochannel Templates For
Si Nanowire Growth And Transistor Fabrication. (Doctoral Dissertation). Penn State University. Retrieved from https://etda.libraries.psu.edu/catalog/18933
Chicago Manual of Style (16th Edition):
Pan, Suxing. “A Novel Approach For Fabricating Nanochannel Templates For
Si Nanowire Growth And Transistor Fabrication.” 2013. Doctoral Dissertation, Penn State University. Accessed December 13, 2018.
https://etda.libraries.psu.edu/catalog/18933.
MLA Handbook (7th Edition):
Pan, Suxing. “A Novel Approach For Fabricating Nanochannel Templates For
Si Nanowire Growth And Transistor Fabrication.” 2013. Web. 13 Dec 2018.
Vancouver:
Pan S. A Novel Approach For Fabricating Nanochannel Templates For
Si Nanowire Growth And Transistor Fabrication. [Internet] [Doctoral dissertation]. Penn State University; 2013. [cited 2018 Dec 13].
Available from: https://etda.libraries.psu.edu/catalog/18933.
Council of Science Editors:
Pan S. A Novel Approach For Fabricating Nanochannel Templates For
Si Nanowire Growth And Transistor Fabrication. [Doctoral Dissertation]. Penn State University; 2013. Available from: https://etda.libraries.psu.edu/catalog/18933
Penn State University
27.
Sarpatwari, Karthik.
Toward Understanding the Electrical Properties of
Metal/Semiconductor Schottky Contacts: the Effects of Barrier
Inhomogeneities and Geometry in Bulk and Nanoscale
Structures.
Degree: PhD, Engineering Science and Mechanics, 2009, Penn State University
URL: https://etda.libraries.psu.edu/catalog/9963
► The work presented in this thesis comprises of two parts. Part I deals with Schottky contacts to the wide bandgap (WBG) semiconductors SiC, GaN and…
(more)
▼ The work presented in this thesis comprises of two
parts. Part I deals with Schottky contacts to the wide bandgap
(WBG) semiconductors SiC, GaN and ZnO. These semiconductors offer
great promise for a wide variety of electronic and optoelectronic
applications. Schottky barriers to WBG semiconductors are
attractive in particular for high temperature/high power diodes,
photodetectors, and gas sensors. However, the Schottky barriers
exhibit non-ideal behavior, due in part to inhomogeneities
originating from immature crystal growth and device processing
technologies. Apart from being a versatile electronic component,
the Schottky diode is a valuable test structure. The Schottky
contact is routinely used to probe substrate and epilayer quality
by different electrical characterization techniques. It is well
established that the current-voltage-temperature (I-V-T)
characteristics of Schottky contacts are routinely affected by the
presence of barrier height inhomogeneities (BHI). Consequently,
Schottky diode parameters such as the Schottky barrier height and
the Richardson constant extracted using the I-V-T measurements can
deviate from their actual values. The effects of BHI on the
extracted Schottky barrier height have been studied in the
literature. However, the effects of BHI on the Richardson constant
have not been thoroughly explored and are the focus of the first
part of this thesis. Based on the inhomogeneous Schottky barrier
model provided by Tung, a new method for the extraction of the
Richardson constant is developed. The new method is applied to the
Richardson constant determination of n-type ZnO and GaN. Excellent
agreement with the theoretical value is obtained in both cases. The
advent of the nanoelectronics era has resulted in the Schottky
contact evolving from the relatively simple, planar structure into
a more complex structure. Compared to bulk Schottky contacts, the
Schottky barrier properties are expected to be widely different at
the nanoscale. For example, the I-V characteristics of nanoscale
Schottky contacts are affected by the contact size and geometry.
Due to the increased surface-to-volume ratio, the conduction
properties of nanoscale Schottky contacts are also influenced by
surface conditions such as surface charge and traps. Depending on
contact size, geometry and surface conditions, an enhanced
tunneling current contribution can be expected, further distorting
the I-V characteristics from the simple thermionic emission model.
Determination of the true Schottky barrier height in nanoscale
contacts to semiconductor nanowires is important from both
technological and fundamental scientific perspectives. In the
second part of this thesis, we employ a simulation-based approach
to study the conduction properties of an axial Schottky nanocontact
to a surround-gate nanowire. A systematic study of the effects of
surface charge on the I-V characteristics of the axial nano
Schottky/nanowire system is undertaken. Based on the study, a
method is proposed to extract the true Schottky barrier height from
the…
Subjects/Keywords: Schottky barrier diodes; Nanowire
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APA ·
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Export
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Manager
APA (6th Edition):
Sarpatwari, K. (2009). Toward Understanding the Electrical Properties of
Metal/Semiconductor Schottky Contacts: the Effects of Barrier
Inhomogeneities and Geometry in Bulk and Nanoscale
Structures. (Doctoral Dissertation). Penn State University. Retrieved from https://etda.libraries.psu.edu/catalog/9963
Chicago Manual of Style (16th Edition):
Sarpatwari, Karthik. “Toward Understanding the Electrical Properties of
Metal/Semiconductor Schottky Contacts: the Effects of Barrier
Inhomogeneities and Geometry in Bulk and Nanoscale
Structures.” 2009. Doctoral Dissertation, Penn State University. Accessed December 13, 2018.
https://etda.libraries.psu.edu/catalog/9963.
MLA Handbook (7th Edition):
Sarpatwari, Karthik. “Toward Understanding the Electrical Properties of
Metal/Semiconductor Schottky Contacts: the Effects of Barrier
Inhomogeneities and Geometry in Bulk and Nanoscale
Structures.” 2009. Web. 13 Dec 2018.
Vancouver:
Sarpatwari K. Toward Understanding the Electrical Properties of
Metal/Semiconductor Schottky Contacts: the Effects of Barrier
Inhomogeneities and Geometry in Bulk and Nanoscale
Structures. [Internet] [Doctoral dissertation]. Penn State University; 2009. [cited 2018 Dec 13].
Available from: https://etda.libraries.psu.edu/catalog/9963.
Council of Science Editors:
Sarpatwari K. Toward Understanding the Electrical Properties of
Metal/Semiconductor Schottky Contacts: the Effects of Barrier
Inhomogeneities and Geometry in Bulk and Nanoscale
Structures. [Doctoral Dissertation]. Penn State University; 2009. Available from: https://etda.libraries.psu.edu/catalog/9963
Penn State University
28.
Kuo, Meng-wei.
Bottom-up and top-down fabrication of nanowire-based
electronic devices:.
Degree: PhD, Electrical Engineering, 2013, Penn State University
URL: https://etda.libraries.psu.edu/catalog/18353
► Semiconductor nanowires are important components in future nanoelectronic and optoelectronic device applications. These nanowires can be fabricated using either bottom-up or top-down methods. While bottom-up…
(more)
▼ Semiconductor nanowires are important components in
future nanoelectronic and optoelectronic device applications. These
nanowires can be fabricated using either bottom-up or top-down
methods. While bottom-up techniques can achieve higher aspect ratio
at reduced dimension without having surface and sub-surface damage,
uniform doping distributions with abrupt junction profiles are less
challenging for top-down methods. In this dissertation, nanowires
fabricated by both methods were systematically investigated to
understand: (1) the in situ incorporation of boron (B) dopants in
Si nanowires grown by the bottom-up vapor-liquid-solid (VLS)
technique, and (2) the impact of plasma-induced etch damage on
InGaAs p+-i-n+ nanowire junctions for tunnel field-effect
transistors (TFETs) applications. In Chapter 2 and 3, the in situ
incorporation of B in Si nanowires grown using silane (SiH4) or
silicon tetrachloride (SiCl4) as the Si precursor and
trimethylboron (TMB) as the p-type dopant source is investigated by
I-V measurements of individual nanowires. The results from
measurements using a global-back-gated test structure reveal
non-uniform B doping profiles on nanowires grown from SiH4, which
is due to simultaneous incorporation of B from nanowire surface and
the catalyst during VLS growth. In contrast, a uniform B doping
profile in both the axial and radial directions is achieved for
TMB-doped Si nanowires grown using SiCl4 at high substrate
temperatures. In Chapter 4, the I-V characteristics of wet- and
dry-etched InGaAs p+-i-n+ junctions with different mesa geometries,
orientations, and perimeter-to-area ratios are compared to evaluate
the impact of the dry etch process on the junction leakage current
properties. Different post-dry etch treatments, including wet
etching and thermal annealing, are performed and the effectiveness
of each is assessed by temperature-dependent I-V measurements. As
compared to wet-etched control devices, dry-etched junctions have a
significantly higher leakage current and a current kink in the
reverse bias regime, which is likely due to additional trap states
created by plasma-induced damage during the Cl2/Ar/H2 mesa
isolation step. These states extend more than 60 nm from the mesa
surface and can only be partially passivated after a thermal anneal
at 350 °C for 20 minutes. The evolution of the electrical properties
with post-dry etch treatments indicates that the shallow and
deep-level trap states resulting from ion-induced point defects,
arsenic vacancies and hydrogen-dopant complexes are the primary
cause of degradation in the electrical properties of the dry-etched
junctions.
Subjects/Keywords: nanowire; VLS; InGaAs; tunnel
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Manager
APA (6th Edition):
Kuo, M. (2013). Bottom-up and top-down fabrication of nanowire-based
electronic devices:. (Doctoral Dissertation). Penn State University. Retrieved from https://etda.libraries.psu.edu/catalog/18353
Chicago Manual of Style (16th Edition):
Kuo, Meng-wei. “Bottom-up and top-down fabrication of nanowire-based
electronic devices:.” 2013. Doctoral Dissertation, Penn State University. Accessed December 13, 2018.
https://etda.libraries.psu.edu/catalog/18353.
MLA Handbook (7th Edition):
Kuo, Meng-wei. “Bottom-up and top-down fabrication of nanowire-based
electronic devices:.” 2013. Web. 13 Dec 2018.
Vancouver:
Kuo M. Bottom-up and top-down fabrication of nanowire-based
electronic devices:. [Internet] [Doctoral dissertation]. Penn State University; 2013. [cited 2018 Dec 13].
Available from: https://etda.libraries.psu.edu/catalog/18353.
Council of Science Editors:
Kuo M. Bottom-up and top-down fabrication of nanowire-based
electronic devices:. [Doctoral Dissertation]. Penn State University; 2013. Available from: https://etda.libraries.psu.edu/catalog/18353
University of Toronto
29.
Lau, Jacky Kai-Tak.
Study of a Semiconductor Nanowire under a Scanning Probe Tip Gate.
Degree: 2010, University of Toronto
URL: http://hdl.handle.net/1807/24597
► Nanowires are sensitive to external influences such as surface charges or external electric fields. An Atomic Force Microsope (AFM) is modified to perform back gating…
(more)
▼ Nanowires are sensitive to external influences such as surface charges or external electric fields. An Atomic Force Microsope (AFM) is modified to perform back gating and tip gating measurements in order to understand the interaction between an external field, and surface charge and nanowire conductance.
A 2D finite element method (FEM) model is developed to simulate the measured conductance. The model shows that surface states play a critical role in determining nanowire conductance. A 3D FEM model is developed to examine the influence of the AFM tip on the lateral resolution of the AFM tip in the electrostatic measurement. The radius of the AFM tip determines the lateral resolution of the tip. However, carrier concentration in the nanowire establishes a lower limit on the lateral resolution, for small tip radii. These results enable one to optimize Scanning Probe Microscopy experiments as well as inform sample preparation for nanowire characterization.
MAST
Advisors/Committee Members: Ruda, Harry E., Electrical and Computer Engineering.
Subjects/Keywords: Nanowire; Scanning Probe; 0544
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Manager
APA (6th Edition):
Lau, J. K. (2010). Study of a Semiconductor Nanowire under a Scanning Probe Tip Gate. (Masters Thesis). University of Toronto. Retrieved from http://hdl.handle.net/1807/24597
Chicago Manual of Style (16th Edition):
Lau, Jacky Kai-Tak. “Study of a Semiconductor Nanowire under a Scanning Probe Tip Gate.” 2010. Masters Thesis, University of Toronto. Accessed December 13, 2018.
http://hdl.handle.net/1807/24597.
MLA Handbook (7th Edition):
Lau, Jacky Kai-Tak. “Study of a Semiconductor Nanowire under a Scanning Probe Tip Gate.” 2010. Web. 13 Dec 2018.
Vancouver:
Lau JK. Study of a Semiconductor Nanowire under a Scanning Probe Tip Gate. [Internet] [Masters thesis]. University of Toronto; 2010. [cited 2018 Dec 13].
Available from: http://hdl.handle.net/1807/24597.
Council of Science Editors:
Lau JK. Study of a Semiconductor Nanowire under a Scanning Probe Tip Gate. [Masters Thesis]. University of Toronto; 2010. Available from: http://hdl.handle.net/1807/24597
Georgia Tech
30.
Sivaram, Saujan Venkat.
The impact of surface chemistry on stable semiconductor nanowire growth.
Degree: PhD, Chemical and Biomolecular Engineering, 2015, Georgia Tech
URL: http://hdl.handle.net/1853/55509
► The vapor-liquid-solid (VLS) mechanism – whereby a liquid eutectic “catalyst” droplet collects precursor molecules (or atoms) from the vapor and directs crystallization of the solid…
(more)
▼ The vapor-liquid-solid (VLS) mechanism – whereby a liquid eutectic “catalyst” droplet collects precursor molecules (or atoms) from the vapor and directs crystallization of the solid
nanowire – is a ubiquitous method for bottom-up
nanowire synthesis. In this thesis, we use in situ infrared absorption spectroscopy to identify the previously unknown, yet critical, role of reactive surface intermediates on semiconductor
nanowire synthesis. We quantitatively determine the surface coverage of hydrogen atoms by coupling operando measurements with a novel in situ surface titration and show these adsorbates are vital for stable Ge
nanowire growth. In the second part of the thesis, we use in situ spectroscopy to explore the interplay between the supercooled AuGe catalyst state and surface chemistry. We find a strong correlation between loss of surface hydrogen and catalyst solidification. To unambiguously identify the influence of surface chemistry on the supercooled AuGe catalyst, we deliver atomic hydrogen to the
nanowire sidewall, which prevents Au migration from the supercooled catalyst and preserves the liquid catalyst state in the absence of Ge2H6 flow. We conclude that solidification likely occurs via heterogeneous nucleation in the presence of solid particles near the trijunction region and present general strategies to maintain the supercooled catalyst state in other material systems. Our experiments identify a key chemical mechanism underlying
nanowire growth via chemical vapor deposition and demonstrate that changes to surface bonding are critical to understand
nanowire synthesis. The fundamental insights shown promise unprecedented control of
nanowire structure and function by providing a chemical foundation for rational synthetic design.
Advisors/Committee Members: Filler, Michael A. (advisor), Grover, Martha A. (committee member), Henderson, Clifford L. (committee member), Fedorov, Andrei G. (committee member), Bongiorno, Angelo (committee member).
Subjects/Keywords: Nanowire; Semiconductor; Synthesis; Spectroscopy
Record Details
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Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Sivaram, S. V. (2015). The impact of surface chemistry on stable semiconductor nanowire growth. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/55509
Chicago Manual of Style (16th Edition):
Sivaram, Saujan Venkat. “The impact of surface chemistry on stable semiconductor nanowire growth.” 2015. Doctoral Dissertation, Georgia Tech. Accessed December 13, 2018.
http://hdl.handle.net/1853/55509.
MLA Handbook (7th Edition):
Sivaram, Saujan Venkat. “The impact of surface chemistry on stable semiconductor nanowire growth.” 2015. Web. 13 Dec 2018.
Vancouver:
Sivaram SV. The impact of surface chemistry on stable semiconductor nanowire growth. [Internet] [Doctoral dissertation]. Georgia Tech; 2015. [cited 2018 Dec 13].
Available from: http://hdl.handle.net/1853/55509.
Council of Science Editors:
Sivaram SV. The impact of surface chemistry on stable semiconductor nanowire growth. [Doctoral Dissertation]. Georgia Tech; 2015. Available from: http://hdl.handle.net/1853/55509
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