subject:(Electrostatic pull in)

Delft University of Technology

1. Sajadi, B. On the mechanics and stability of micro-plates in electrically loaded MEMS devices.

Degree: 2017, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; urn:NBN:nl:ui:24-uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; 7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; 10.4233/uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; urn:isbn:978-94-6233-844-9 ; urn:NBN:nl:ui:24-uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; http://resolver.tudelft.nl/uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47

► In the last decades, Micro-Electro-Mechanical Systems (MEMS) have drawn immense attention due to their potential use in a wide variety of modern applications, including micro-mechanical… (more)

▼ In the last decades, Micro-Electro-Mechanical Systems (MEMS) have drawn immense attention due to their potential use in a wide variety of modern applications, including micro-mechanical sensors and actuators. MEMS are devices combining mechanical and electrical components between 1 and 100 micrometers, all integrated into a single chip. The performance of these devices hinges on the deflection and movement of these micro-mechanical components and clearly, improvement and innovation of MEMS require a comprehensive knowledge and in-depth understanding of the nonlinear mechanics of these components. In spite of the simple geometry of common micro-mechanical components, modeling the mechanics of micro-mechanical sensors and actuators is rather complex. In particular, the mechanics of micro-plates in electrostatic MEMS is entangled with two influential sources of nonlinearity namely, geometrical nonlinearity and the nonlinearity due to the presence of the electric field. These sources of nonlinearity are often the origin of instability and failure in MEMS devices, but might also be exploited to achieve, for example, higher sensitivity in the device. In either way, such nonlinearities shall be incorporated in the modeling and design of these micro-mechanical components. This thesis provides an investigation on nonlinear mechanics of micro-plates in electrostatic MEMS devices. Based on the proposed models, we are able to predict some phenomena in micro-plates that have not been noticed before and to study these aspects in a detailed level which was not possible previously. In particular, based on total potential energy and a Lagrangian approach, the nonlinear mechanics and stability of a clamped circular micro-plate in interaction with an electrostatic field is studied. The effects of different loading conditions (i.e. static and dynamic electric potential, and with or without the presence of a differential pressure) on the stability of such a system are addressed. The results of this study suggest that in presence of a differential pressure the steady-state motion of an electrically actuated micro-plate can be bi-stable or even multi-stable. In fact, a differential pressure can cause additional limit points and an unstable solution branch in the -static or dynamic- steady state solutions of the system. Saddle-node and period doubling bifurcations are repeatedly observed in the results and are recognized as main mechanisms of pull-in. Furthermore, one newly observed critical point in static loading is shown to be highly sensitive to the applied differential pressure suggesting the possibility of employing this limit point for sensing applications. In addition, this thesis provides a study on analyzing nano-plates within the framework of continuum mechanics. In this regard, the nonlinear vibrations of an electrically actuated graphene resonator is modeled and a methodology is proposed for characterization of its mechanical properties. In addition, the possibility of capturing the scaling… Advisors/Committee Members: van Keulen, A., Goosen, J.F.L., Delft University of Technology.

Subjects/Keywords: Stability; Micro-Plates; nonlinear dynamics; bifurcation; Electrostatic MEMS; Pull-in; nonlinear mechanics

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APA (6^th Edition):

Sajadi, B. (2017). On the mechanics and stability of micro-plates in electrically loaded MEMS devices. (Doctoral Dissertation). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; urn:NBN:nl:ui:24-uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; 7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; 10.4233/uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; urn:isbn:978-94-6233-844-9 ; urn:NBN:nl:ui:24-uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; http://resolver.tudelft.nl/uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47

Chicago Manual of Style (16^th Edition):

Sajadi, B. “On the mechanics and stability of micro-plates in electrically loaded MEMS devices.” 2017. Doctoral Dissertation, Delft University of Technology. Accessed April 22, 2021. http://resolver.tudelft.nl/uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; urn:NBN:nl:ui:24-uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; 7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; 10.4233/uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; urn:isbn:978-94-6233-844-9 ; urn:NBN:nl:ui:24-uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; http://resolver.tudelft.nl/uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47.

MLA Handbook (7^th Edition):

Sajadi, B. “On the mechanics and stability of micro-plates in electrically loaded MEMS devices.” 2017. Web. 22 Apr 2021.

Vancouver:

Sajadi B. On the mechanics and stability of micro-plates in electrically loaded MEMS devices. [Internet] [Doctoral dissertation]. Delft University of Technology; 2017. [cited 2021 Apr 22]. Available from: http://resolver.tudelft.nl/uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; urn:NBN:nl:ui:24-uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; 7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; 10.4233/uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; urn:isbn:978-94-6233-844-9 ; urn:NBN:nl:ui:24-uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; http://resolver.tudelft.nl/uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47.

Council of Science Editors:

Sajadi B. On the mechanics and stability of micro-plates in electrically loaded MEMS devices. [Doctoral Dissertation]. Delft University of Technology; 2017. Available from: http://resolver.tudelft.nl/uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; urn:NBN:nl:ui:24-uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; 7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; 10.4233/uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; urn:isbn:978-94-6233-844-9 ; urn:NBN:nl:ui:24-uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47 ; http://resolver.tudelft.nl/uuid:7ec08141-8ea9-4a7e-923c-b01d9a367b47

2. Pluimers, L.M. (author). Feasibility Study for AFM Probe Calibration using the Probe’s Electrostatic Pull-in Stability.

Degree: 2013, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:e19c09fd-ec28-4a54-bd5e-affd2dc428da

Precision and Microsystems Engineering

Mechanical, Maritime and Materials Engineering

Advisors/Committee Members: Van Spengen, W.M. (mentor).

Subjects/Keywords: AFM Probe; Calibration; Electrostatic; Pull-in; Stability

…3 Electrostatic Pull-in Instability for AFM cantilever calibration 3-1 Introduction to EPI… …of their projects is the calibration of AFM probes using the Electrostatic Pull-in… …cantilever beam can be determined using this electrostatic pull-in instability. The EPI calibration… …is called the Electrostatic Pull-in Instability (EPI) method. In this master… …In chapter 3, a model is made to describe the probe’s electrostatic pull-in behaviour. In…

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APA (6^th Edition):

Pluimers, L. M. (. (2013). Feasibility Study for AFM Probe Calibration using the Probe’s Electrostatic Pull-in Stability. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:e19c09fd-ec28-4a54-bd5e-affd2dc428da

Chicago Manual of Style (16^th Edition):

Pluimers, L M (author). “Feasibility Study for AFM Probe Calibration using the Probe’s Electrostatic Pull-in Stability.” 2013. Masters Thesis, Delft University of Technology. Accessed April 22, 2021. http://resolver.tudelft.nl/uuid:e19c09fd-ec28-4a54-bd5e-affd2dc428da.

MLA Handbook (7^th Edition):

Pluimers, L M (author). “Feasibility Study for AFM Probe Calibration using the Probe’s Electrostatic Pull-in Stability.” 2013. Web. 22 Apr 2021.

Vancouver:

Pluimers LM(. Feasibility Study for AFM Probe Calibration using the Probe’s Electrostatic Pull-in Stability. [Internet] [Masters thesis]. Delft University of Technology; 2013. [cited 2021 Apr 22]. Available from: http://resolver.tudelft.nl/uuid:e19c09fd-ec28-4a54-bd5e-affd2dc428da.

Council of Science Editors:

Pluimers LM(. Feasibility Study for AFM Probe Calibration using the Probe’s Electrostatic Pull-in Stability. [Masters Thesis]. Delft University of Technology; 2013. Available from: http://resolver.tudelft.nl/uuid:e19c09fd-ec28-4a54-bd5e-affd2dc428da

3. Molenaar, E.P. (author). Feasibility Study and Design of AFM Production Wafer Calibration Method using Electrostatic Pull-in Instability.

Degree: 2013, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:a64e6ff5-eb0c-4f30-987e-356c57123fe7

Precision and Microsystems Engineering

Mechanical, Maritime and Materials Engineering

Advisors/Committee Members: Staufer, U. (mentor).

Subjects/Keywords: MEMS; AFM; Probe; Electrostatic; Pull-in; Cantilever

…Electrostatic Pull-in Instability (EPI) . . . . . . . . . . . . . . . . . . . . . . . . 21… …21 3-2-2 Electrostatic Pull-In used as a calibration method . . . . . . . . . . . . . 3-3… …1 Modeling Electrostatic Pull-in… …is based on the Electrostatic Pull-in Instability, or EPI, of cantilever beams. Initial… …Schematic overview of the structures used in electrostatic calibration. . . . 17 (c)…

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APA (6^th Edition):

Molenaar, E. P. (. (2013). Feasibility Study and Design of AFM Production Wafer Calibration Method using Electrostatic Pull-in Instability. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:a64e6ff5-eb0c-4f30-987e-356c57123fe7

Chicago Manual of Style (16^th Edition):

Molenaar, E P (author). “Feasibility Study and Design of AFM Production Wafer Calibration Method using Electrostatic Pull-in Instability.” 2013. Masters Thesis, Delft University of Technology. Accessed April 22, 2021. http://resolver.tudelft.nl/uuid:a64e6ff5-eb0c-4f30-987e-356c57123fe7.

MLA Handbook (7^th Edition):

Molenaar, E P (author). “Feasibility Study and Design of AFM Production Wafer Calibration Method using Electrostatic Pull-in Instability.” 2013. Web. 22 Apr 2021.

Vancouver:

Molenaar EP(. Feasibility Study and Design of AFM Production Wafer Calibration Method using Electrostatic Pull-in Instability. [Internet] [Masters thesis]. Delft University of Technology; 2013. [cited 2021 Apr 22]. Available from: http://resolver.tudelft.nl/uuid:a64e6ff5-eb0c-4f30-987e-356c57123fe7.

Council of Science Editors:

Molenaar EP(. Feasibility Study and Design of AFM Production Wafer Calibration Method using Electrostatic Pull-in Instability. [Masters Thesis]. Delft University of Technology; 2013. Available from: http://resolver.tudelft.nl/uuid:a64e6ff5-eb0c-4f30-987e-356c57123fe7

4. ZHAO YI. Linearization and control of dual-axis micromirror.

Degree: 2006, National University of Singapore

URL: http://scholarbank.nus.edu.sg/handle/10635/15767

Subjects/Keywords: MEMS; Dual-Axis Micromirror; Electrostatic Actuation; Scanning Nonlinearity; Lineariztion; Pull-in Instability

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

YI, Z. (2006). Linearization and control of dual-axis micromirror. (Thesis). National University of Singapore. Retrieved from http://scholarbank.nus.edu.sg/handle/10635/15767

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

YI, ZHAO. “Linearization and control of dual-axis micromirror.” 2006. Thesis, National University of Singapore. Accessed April 22, 2021. http://scholarbank.nus.edu.sg/handle/10635/15767.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

YI, ZHAO. “Linearization and control of dual-axis micromirror.” 2006. Web. 22 Apr 2021.

Vancouver:

YI Z. Linearization and control of dual-axis micromirror. [Internet] [Thesis]. National University of Singapore; 2006. [cited 2021 Apr 22]. Available from: http://scholarbank.nus.edu.sg/handle/10635/15767.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

YI Z. Linearization and control of dual-axis micromirror. [Thesis]. National University of Singapore; 2006. Available from: http://scholarbank.nus.edu.sg/handle/10635/15767

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

5. Kim, Doyoung. Nanoscale electrostatic actuators in liquid electrolytes: analysis and experiment.

Degree: PhD, Aerospace Engineering, 2006, Texas A&M University

URL: http://hdl.handle.net/1969.1/3079

► The objective of this dissertation is to analytically model a parallel plate electrostatic actuator operating in a liquid electrolyte and experimentally verify the analysis. The… (more)

▼ The objective of this dissertation is to analytically model a parallel plate electrostatic actuator operating in a liquid electrolyte and experimentally verify the analysis. The model assumes the system remains in thermodynamic equilibrium during actuation, which enables the ion mass balance equations and GuassÂ Law to be combined into the Poisson-Boltzmann equation. The governing equations also include the linear momentum equation including the following forces: the electric force, the osmotic force, the spring force, the viscous damping force, and the van der Waals force. Equations are also derived for the energy stored in the actuator. The analytical results emphasize the stored energy at mechanical equilibrium and the voltage versus electrode separation behavior including the instability. The analytical results predict that the system may not be a good actuator because the displacement has a very limited stable range, although the actuator would be suitable for bistable applications. The experiment consisted of a fixed flat gold electrode and a movable gold electrode consisting of a gold sphere several micrometers in diameter mounted on the end of an Atomic Force Microscope (AFM) cantilever, which serves as the spring. The electrodes were separated by approximately 100nm of 1mM NaCl aqueous solution. The analytical results were not verified by the experiment. Relative to the analysis, the experiments did not show distinct critical points, and the experiments showed less electrode separation for a given applied electric potential. The experiments did show points at which the electrode separation versus electric potential rapidly changed slope, which may be instability points. It is suggested that this phenomenon may be due to coalesced gas bubbles on hydrophobic regions of the electrode surfaces, which are not included in the model. Although clean gold surfaces are hydrophilic, gold surfaces may become hydrophobic due to impurities. Advisors/Committee Members: Boyd, James G. (advisor), Hurtado, Johnny (committee member), Kim, Won-jong (committee member), Whitcomb, John D. (committee member).

Subjects/Keywords: nanoscale; electrostatic actuators; electrolytes; pull-in instability

…force and electrostatic force below the critical pull-in potential in Fig. 5 correspond to the… …45 3) Pull-in instability… …Elastic spring force and electrostatic force vs. distance of electrostatic actuator in the gas… …chemical, and thermal energy. Electrostatic actuators are the most common type of actuator in… …The parallel plate actuators undergo a “snap-down” or “pull-in” instability in which the two…

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Kim, D. (2006). Nanoscale electrostatic actuators in liquid electrolytes: analysis and experiment. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/3079

Chicago Manual of Style (16^th Edition):

Kim, Doyoung. “Nanoscale electrostatic actuators in liquid electrolytes: analysis and experiment.” 2006. Doctoral Dissertation, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/3079.

MLA Handbook (7^th Edition):

Kim, Doyoung. “Nanoscale electrostatic actuators in liquid electrolytes: analysis and experiment.” 2006. Web. 22 Apr 2021.

Vancouver:

Kim D. Nanoscale electrostatic actuators in liquid electrolytes: analysis and experiment. [Internet] [Doctoral dissertation]. Texas A&M University; 2006. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/3079.

Council of Science Editors:

Kim D. Nanoscale electrostatic actuators in liquid electrolytes: analysis and experiment. [Doctoral Dissertation]. Texas A&M University; 2006. Available from: http://hdl.handle.net/1969.1/3079

6. Wickramasinghe, Imiya M. Passivity-based stabilization of a 1-DOF electrostatic MEMS model with a parasitic capacitance.

Degree: Mechanical Engineering, 2008, Texas Tech University

URL: http://hdl.handle.net/2346/22651

► This thesis addresses the problem of stabilizing 1-DOF piston mode electrostatic actuator in the presence of parasitic capacitance due to conductive substrate. The current study… (more)

Subjects/Keywords: Charge pull-In; Parasitics; Electrostatic; Microelectromechanical systems

…gap is to be controlled by electrostatic actuation the fundamental nature of pull-in has to… …charge-controlled electrostatic MEMS through a saddle-node bifurcation known as charge pull-in… …phenomenon of voltage pull-in associated with voltage control of electrostatic MEMS is well known… …II ≥ 0.5, charge pull-in occurs at the points marked by an ‘x.’ Stable branches are solid… …proposal for total charge based control to eliminate charge pull-in. The work of this thesis…

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APA (6^th Edition):

Wickramasinghe, I. M. (2008). Passivity-based stabilization of a 1-DOF electrostatic MEMS model with a parasitic capacitance. (Thesis). Texas Tech University. Retrieved from http://hdl.handle.net/2346/22651

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wickramasinghe, Imiya M. “Passivity-based stabilization of a 1-DOF electrostatic MEMS model with a parasitic capacitance.” 2008. Thesis, Texas Tech University. Accessed April 22, 2021. http://hdl.handle.net/2346/22651.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wickramasinghe, Imiya M. “Passivity-based stabilization of a 1-DOF electrostatic MEMS model with a parasitic capacitance.” 2008. Web. 22 Apr 2021.

Vancouver:

Wickramasinghe IM. Passivity-based stabilization of a 1-DOF electrostatic MEMS model with a parasitic capacitance. [Internet] [Thesis]. Texas Tech University; 2008. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/2346/22651.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wickramasinghe IM. Passivity-based stabilization of a 1-DOF electrostatic MEMS model with a parasitic capacitance. [Thesis]. Texas Tech University; 2008. Available from: http://hdl.handle.net/2346/22651

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universidade do Minho

7. Dias, Rosana Maria Alves. Micro-g MEMS accelerometer based on time measurement.

Degree: 2013, Universidade do Minho

URL: http://hdl.handle.net/1822/24893

► Nas últimas décadas assistiu-se a um imenso crescimento no mercado de sensors MEMS, tendo os acelerómetros sido uma das maiores forças impulsionadoras desse crescimento devido… (more)

▼ Nas últimas décadas assistiu-se a um imenso crescimento no mercado de sensors MEMS, tendo os acelerómetros sido uma das maiores forças impulsionadoras desse crescimento devido às suas aplicações na indústria automóvel. Desde então, a gama de aplicações destes sensores expandiu-se multidirecionalmente, novas aplicações emergiram e acelerómetros convencionais em aplicações já existentes foram substituídos por acelerómetros MEMS. Isto deve-se essencialmente ao seu baixo custo e pequenas dimensões. Há no entanto, aplicações para as quais o desempenho dos acelerómetros MEMS ainda não é suficiente. O objectivo deste trabalho é desenvolver um acelerómetro de elevado desempenho tirando partido da elevada sensibilidade do efeito de pull-in a forças externas tais como a aceleração. O efeito de pull-in, descrito pela primeira vez há mais de 40 anos, ocorre em dispositivos capacitivos com partes móveis. Este é um efeito não-linear geralmente evitado/indesejado, uma vez que se traduz numa instabilidade que dificulta o controlo da posição das partes móveis. Na última década foi dedicada alguma investigaçao científica a este fenómeno, tendo sido descoberta a existência de um perfil de deslocamento particular, denominado meta-estabilidade, em determinadas condições de amortecimento e de actuação electrostática. Esta característica do pull-in torna a sua duração extremamente sensível a variações nas forças intervenientes, incluindo aceleração externa. Assim sendo, a medição do tempo de pull-in de micro-estruturas especificamente concebidas para o efeito pode ser utilizada para medir aceleração. Esta abordagem apresenta vantagens significativas em comparação com a transdução direta de capacidade para aceleração (caso da generalidade dos acelerómetros capacitivos). Nomeadamente, a variável tempo pode ser medida com elevada precisão com relativa facilidade e sem necessidade de desenvolvimentos tecnológicos (o que não é o caso da medição de capacidade). Por exemplo, o uso de uma frequência de relógio de 100 MHz no mecanismo de contagem de tempo permite uma resolução de 100 ns na medição de tempo, o que corresponde, considerando a sensibilidade de 0.26 μs/μg do acelerómetro desenvolvido neste trabalho, a uma resolução na medição de acceleração de 0.38μg. Um dos maiores desafios do desenvolvimento de um acelerómetro baseado no tempo de pull-in é o desenho do amortecedor, pois a sensibilidade e o ruído/resolução do sensor final dependem do nível de amortecimento. Uma nova geometria para o amortecedor (estabelecido por um mecanismo de squeeze-film) é apresentada e estudada neste trabalho. Esta consiste em abrir canais nas placas paralelas facilitando assim o fluxo de ar quando as placas se movem. Ficou provado que esta geometria é eficaz na redução da razão capacidade/amortecimento, o que constituía um problema recorrente no desenho de dispositivos de placas paralelas in-plane. Neste trabalho é descrito o desenvolvimento de um acelerómetro em malha aberta com uma sensibilidade de 0.26 μs/μg e 2.7 μg /√Hz de… Advisors/Committee Members: Rocha, Luís A. (advisor), Correia, J. H. (advisor).

Subjects/Keywords: Pull-in; MEMS; accelerometer; noise; parallel-plates; damping; electrostatic feedback; gas viscosity; acelerómetro; placas-paralelas; amortecimento; feeback electrostático; viscosidade de gas

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Dias, R. M. A. (2013). Micro-g MEMS accelerometer based on time measurement. (Doctoral Dissertation). Universidade do Minho. Retrieved from http://hdl.handle.net/1822/24893

Chicago Manual of Style (16^th Edition):

Dias, Rosana Maria Alves. “Micro-g MEMS accelerometer based on time measurement.” 2013. Doctoral Dissertation, Universidade do Minho. Accessed April 22, 2021. http://hdl.handle.net/1822/24893.

MLA Handbook (7^th Edition):

Dias, Rosana Maria Alves. “Micro-g MEMS accelerometer based on time measurement.” 2013. Web. 22 Apr 2021.

Vancouver:

Dias RMA. Micro-g MEMS accelerometer based on time measurement. [Internet] [Doctoral dissertation]. Universidade do Minho; 2013. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1822/24893.

Council of Science Editors:

Dias RMA. Micro-g MEMS accelerometer based on time measurement. [Doctoral Dissertation]. Universidade do Minho; 2013. Available from: http://hdl.handle.net/1822/24893

University of Notre Dame

8. Jie Su. A Lateral-Drive Method to Address Pull-in Failure in MEMS</h1>.

Degree: Electrical Engineering, 2008, University of Notre Dame

URL: https://curate.nd.edu/show/0g354f1841c

► Electrostatic drive is the most common actuation method in MEMS due to its low power, simplicity and ability to generate large forces. However, an… (more)

Subjects/Keywords: MEMS; Actuator; Fabry-Perot; Pull-in; Electrostatic

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Su, J. (2008). A Lateral-Drive Method to Address Pull-in Failure in MEMS</h1>. (Thesis). University of Notre Dame. Retrieved from https://curate.nd.edu/show/0g354f1841c

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Su, Jie. “A Lateral-Drive Method to Address Pull-in Failure in MEMS</h1>.” 2008. Thesis, University of Notre Dame. Accessed April 22, 2021. https://curate.nd.edu/show/0g354f1841c.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Su, Jie. “A Lateral-Drive Method to Address Pull-in Failure in MEMS</h1>.” 2008. Web. 22 Apr 2021.

Vancouver:

Su J. A Lateral-Drive Method to Address Pull-in Failure in MEMS</h1>. [Internet] [Thesis]. University of Notre Dame; 2008. [cited 2021 Apr 22]. Available from: https://curate.nd.edu/show/0g354f1841c.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Su J. A Lateral-Drive Method to Address Pull-in Failure in MEMS</h1>. [Thesis]. University of Notre Dame; 2008. Available from: https://curate.nd.edu/show/0g354f1841c

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Oxford

9. Gomez, Michael. Ghosts and bottlenecks in elastic snap-through.

Degree: PhD, 2018, University of Oxford

URL: http://ora.ox.ac.uk/objects/uuid:11ab7b19-ee4b-4cd6-ac9a-116363a4e4d7 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.757801

► Snap-through is a striking instability in which an elastic object rapidly jumps from one state to another. It is seen in the leaves of the… (more)

▼ Snap-through is a striking instability in which an elastic object rapidly jumps from one state to another. It is seen in the leaves of the Venus flytrap plant and umbrellas flipping on a windy day among many other examples. Similar structures that snap-through are used to generate fast motions in soft robotics, switches in micro-scale electronics and artificial heart valves. Despite the ubiquity of snap-through in nature and engineering, its dynamics is usually only understood qualitatively. In this thesis we develop analytical understanding of this dynamics, focussing on how the mathematical structure underlying the snap-through transition controls the timescale of instability. We begin by considering the dynamics of 'pull-in' instabilities in microelectromechanical systems (MEMS) - a type of snap-through caused by electrostatic forces in which the motions are dominated by fluid damping. Using a lumped-parameter model, we show that the observed time delay near the pull-in transition is a type of critical slowing down - a so-called 'bottleneck' due to the 'ghost' of a saddle-node bifurcation. We obtain a scaling law describing this slowing down, and, in the process, unify a large range of experiments and simulations that exhibit delay phenomena during pull-in. We also investigate the pull-in dynamics of MEMS microbeams, extending the lumped-parameter approach to incorporate the details of the beam geometry. This provides a model system in which to understand snap-through of a continuous elastic structure due to external loading. We develop a perturbation method that systematically exploits the proximity to pull-in to reduce the governing equations to a simpler evolution equation, with a structure that highlights the saddle-node bifurcation. This allows us to analyse the bottleneck dynamics in detail, which we compare with previous experimental and numerical data. The remainder of the thesis is concerned with the dynamics of snap-through in macroscopic systems. In particular, we explore the extent to which dissipation is required to explain anomalously slow snap-through. Considering an elastic arch as an archetype of a snapping system, we use the perturbation method developed earlier to show that two bottleneck regimes are possible, depending delicately on the relative importance of external damping. In particular, we show that critical slowing down occurs even in the absence of damping, leading to a new scaling law for the snap-through time that is confirmed by elastica simulations and experiments. In many real systems material viscoelasticity is present to some degree. Finally, we examine how this influences the snap-through dynamics of a simple truss-like structure. We present a regime diagram that characterises when the timescale of snap-through is controlled by viscous, elastic or viscoelastic effects.

Subjects/Keywords: 510; Applied Mathematics; MEMS; Elasticity; Viscoelasticity; Bistability; Snap-through; Microbeam; Creep; Saddle-node ghost; Dynamics; Instability; Buckling; Electrostatic pull-in; Critical slowing down; Elastic arch

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APA (6^th Edition):

Gomez, M. (2018). Ghosts and bottlenecks in elastic snap-through. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:11ab7b19-ee4b-4cd6-ac9a-116363a4e4d7 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.757801

Chicago Manual of Style (16^th Edition):

Gomez, Michael. “Ghosts and bottlenecks in elastic snap-through.” 2018. Doctoral Dissertation, University of Oxford. Accessed April 22, 2021. http://ora.ox.ac.uk/objects/uuid:11ab7b19-ee4b-4cd6-ac9a-116363a4e4d7 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.757801.

MLA Handbook (7^th Edition):

Gomez, Michael. “Ghosts and bottlenecks in elastic snap-through.” 2018. Web. 22 Apr 2021.

Vancouver:

Gomez M. Ghosts and bottlenecks in elastic snap-through. [Internet] [Doctoral dissertation]. University of Oxford; 2018. [cited 2021 Apr 22]. Available from: http://ora.ox.ac.uk/objects/uuid:11ab7b19-ee4b-4cd6-ac9a-116363a4e4d7 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.757801.

Council of Science Editors:

Gomez M. Ghosts and bottlenecks in elastic snap-through. [Doctoral Dissertation]. University of Oxford; 2018. Available from: http://ora.ox.ac.uk/objects/uuid:11ab7b19-ee4b-4cd6-ac9a-116363a4e4d7 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.757801

Virginia Tech

10. Younis, Mohammad Ibrahim. Modeling and Simulation of Microelectromechanical Systems in Multi-Physics Fields.

Degree: PhD, Engineering Science and Mechanics, 2004, Virginia Tech

URL: http://hdl.handle.net/10919/11202

► The first objective of this dissertation is to present hybrid numerical-analytical approaches and reduced-order models to simulate microelectromechanical systems (MEMS) in multi-physics fields. These include… (more)

▼ The first objective of this dissertation is to present hybrid numerical-analytical approaches and reduced-order models to simulate microelectromechanical systems (MEMS) in multi-physics fields. These include electric actuation (AC and DC), squeeze-film damping, thermoelastic damping, and structural forces. The second objective is to investigate MEMS phenomena, such as squeeze-film damping and dynamic pull-in, and use the latter to design a novel RF-MEMS switch. In the first part of the dissertation, we introduce a new approach to the modeling and simulation of flexible microstructures under the coupled effects of squeeze-film damping, electrostatic actuation, and mechanical forces. The new approach utilizes the compressible Reynolds equation coupled with the equation governing the plate deflection. The model accounts for the slip condition of the flow at very low pressures. Perturbation methods are used to derive an analytical expression for the pressure distribution in terms of the structural mode shapes. This expression is substituted into the plate equation, which is solved in turn using a finite-element method for the structural mode shapes, the pressure distributions, the natural frequencies, and the quality factors. We apply the new approach to a variety of rectangular and circular plates and present the final expressions for the pressure distributions and quality factors. We extend the approach to microplates actuated by large electrostatic forces. For this case, we present a low-order model, which reduces significantly the cost of simulation. The model utilizes the nonlinear Euler-Bernoulli beam equation, the von K´arm´an plate equations, and the compressible Reynolds equation. The second topic of the dissertation is thermoelastic damping. We present a model and analytical expressions for thermoelastic damping in microplates. We solve the heat equation for the thermal flux across the microplate, in terms of the structural mode shapes, and hence decouple the thermal equation from the plate equation. We utilize a perturbation method to derive an analytical expression for the quality factor of a microplate with general boundary conditions under electrostatic loading and residual stresses in terms of its structural mode shapes. We present results for microplates with various boundary conditions. In the final part of the dissertation, we present a dynamic analysis and simulation of MEMS resonators and novel RF MEMS switches employing resonant microbeams. We first study microbeams excited near their fundamental natural frequencies (primary-resonance excitation). We investigate the dynamic pull-in instability and formulate safety criteria for the design of MEMS sensors and RF filters. We also utilize this phenomenon to design a low-voltage RF MEMS switch actuated with a combined DC and AC loading. Then, we simulate the dynamics of microbeams excited near half their fundamental natural frequencies (superharmonic excitation) and twice their fundamental natural… Advisors/Committee Members: Nayfeh, Ali H. (committeechair), Masoud, Ziyad N. (committee member), Ragab, Saad A. (committee member), Leo, Donald J. (committee member), Hendricks, Scott L. (committee member).

Subjects/Keywords: Primary and Secondary Excitations; Singular Perturbation; Dynamic Pull-in; Finite Element; RF Switches; Microbeams; Microplates; MEMS; Electrostatic Actuation; Thermoelastic Damping; Squeeze-Film Damping; Resonators

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Younis, M. I. (2004). Modeling and Simulation of Microelectromechanical Systems in Multi-Physics Fields. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/11202

Chicago Manual of Style (16^th Edition):

Younis, Mohammad Ibrahim. “Modeling and Simulation of Microelectromechanical Systems in Multi-Physics Fields.” 2004. Doctoral Dissertation, Virginia Tech. Accessed April 22, 2021. http://hdl.handle.net/10919/11202.

MLA Handbook (7^th Edition):

Younis, Mohammad Ibrahim. “Modeling and Simulation of Microelectromechanical Systems in Multi-Physics Fields.” 2004. Web. 22 Apr 2021.

Vancouver:

Younis MI. Modeling and Simulation of Microelectromechanical Systems in Multi-Physics Fields. [Internet] [Doctoral dissertation]. Virginia Tech; 2004. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/10919/11202.

Council of Science Editors:

Younis MI. Modeling and Simulation of Microelectromechanical Systems in Multi-Physics Fields. [Doctoral Dissertation]. Virginia Tech; 2004. Available from: http://hdl.handle.net/10919/11202

Virginia Tech

11. Younis, Mohammad Ibrahim. Investigation of the Mechanical Behavior of Microbeam-Based MEMS Devices.

Degree: MS, Engineering Science and Mechanics, 2001, Virginia Tech

URL: http://hdl.handle.net/10919/31032

► An investigation into the responses of microbeams to electric actuations is presented. Attention is focused mainly on the use of microbeams in two important MEMS-based… (more)

▼ An investigation into the responses of microbeams to electric actuations is presented. Attention is focused mainly on the use of microbeams in two important MEMS-based devices: capacitive microswitches and resonant microsensors. Nonlinear models are developed to simulate the behavior of the microbeams in each device. The models account for mid-plane stretching, an applied axial load, a DC electrostatic force, and, for the case of resonant sensors, an AC harmonic force. Further, a novel method that uses a reduced-order model is introduced for simulating the behavior of microbeams under a DC electrostatic force. The presented method shows attractive features, like for example, a high stability near the pull-in and a low computational cost. Thus, it can be of significant benefit to the development of MEMS design software. The static behavior of microbeams under electrostatic forces is studied using two methods. One method employs a shooting technique for solving the boundary-value problem that governs the static behavior. The second method is based on solving an algebraic system of equations obtained from the reduced-order model. Further, the eigenvalue problem describing the vibrations of a microbeam around its statically deflected position is solved using a shooting method to obtain the microbeam mode shapes and natural frequencies. The dynamic behavior of resonant microbeams is also investigated. A perturbation method, the method of multiple scales, is used to obtain two first-order nonlinear ordinary-differential equations that describe the amplitude and phase of the response and its stability. The results show that an inaccurate representation of the system nonlinearities may lead to an erroneous prediction of the nonlinear resonance frequency of a microbeam. The case of three-to-one internal resonance between the lowest two modes is treated. Finally, the reduced-order model is used to study the dynamic behavior of the electrostatically actuated microbeams. The proposed models are validated by comparing their results with experimental results available in the literature. Advisors/Committee Members: Nayfeh, Ali H. (committeechair).

Subjects/Keywords: MEMS; Pull-in; Capacitive Microswitches; Electrostatic Resonators; Reduced-Order Model

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Younis, M. I. (2001). Investigation of the Mechanical Behavior of Microbeam-Based MEMS Devices. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/31032

Chicago Manual of Style (16^th Edition):

Younis, Mohammad Ibrahim. “Investigation of the Mechanical Behavior of Microbeam-Based MEMS Devices.” 2001. Masters Thesis, Virginia Tech. Accessed April 22, 2021. http://hdl.handle.net/10919/31032.

MLA Handbook (7^th Edition):

Younis, Mohammad Ibrahim. “Investigation of the Mechanical Behavior of Microbeam-Based MEMS Devices.” 2001. Web. 22 Apr 2021.

Vancouver:

Younis MI. Investigation of the Mechanical Behavior of Microbeam-Based MEMS Devices. [Internet] [Masters thesis]. Virginia Tech; 2001. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/10919/31032.

Council of Science Editors:

Younis MI. Investigation of the Mechanical Behavior of Microbeam-Based MEMS Devices. [Masters Thesis]. Virginia Tech; 2001. Available from: http://hdl.handle.net/10919/31032

12. Kärkkäinen, Anna-Maija. MEMS Based Voltage References.

Degree: 2006, VTT Technical Research Centre of Finland

URL: http://lib.tkk.fi/Diss/2006/isbn9513868605/

► Voltage references are fundamental building blocks in many instruments like data logging systems, digital multimeters, and calibrators. State-of-the-art DC voltage references are large and expensive… (more)

▼ Voltage references are fundamental building blocks in many instruments like data logging systems, digital multimeters, and calibrators. State-of-the-art DC voltage references are large and expensive Josephson voltage standards, operated at cryogenic temperatures. On the other hand, small and affordable Zener diodes are noisy and require temperature compensation, so there is a gap to be filled between these devices. The situation regarding AC voltage references is even worse. There are no references fundamentally based on AC, beside the AC Josephson voltage standard. Usually AC references are based on generating an AC voltage from DC, and respectively, an AC voltage is measured by converting it to DC. Hence, a small and affordable MEMS based AC voltage reference would be a very unique device. The excellent mechanical properties of silicon microelectromechanical systems (MEMS) have been demonstrated in many commercial applications. Currently the performance of the components is limited by electrostatic instability phenomena and mechanical stress effects arising from component mounting and packaging. However, when these problems are solved, new application areas open up for micromechanical components, for example, in voltage metrology. The stability of a MEMS based voltage reference is ultimately based on mechanical properties of one of the most stable materials: single crystal silicon. This dissertation reports a DC voltage reference and an AC voltage reference based on the pull-in voltage, a characteristic property of an electrostatic MEMS component. First a brief introduction to voltage metrology and MEMS is given, then methods available for making MEMS based voltage references are discussed, and finally results are presented. The results are divided into three Sections: design and manufacturing of the components, readout electronics, and measurement results of the reference long-term stability. The stability of the reference voltage is of major importance in metrological applications and it is studied both theoretically and experimentally in this work. A detailed analysis of the electromechanical coupling of MEMS components is presented. Due to the lack of an appropriate text book, a majority of the formulas are derived from the basic equations by the author, including also those presented in the Methods Section. Component manufacturing, design and materials choices are also discussed focusing on the stability issue. In the experimental part of this work a DC voltage reference and an AC voltage reference were designed, manufactured and characterized. Also two MEMS moving plate capacitors were designed: one optimised for use as a DC reference and the other optimised for use as an AC reference. The capacitor electrodes required metallizing which could not be manufactured using the existing processes. Hence a new silicon-on-insulator (SOI) manufacturing process utilising low temperature fusion bonding was developed. The stability of the AC voltage reference presented in this dissertation is at ppm-level (10−6).… Advisors/Committee Members: Helsinki University of Technology, Department of Electrical and Communications Engineering.

Subjects/Keywords: MEMS; micro electromechanical systems; DC voltage reference; AC voltage reference; electrostatic charging; pull-in voltage; long-term stability; micromachining

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Kärkkäinen, A. (2006). MEMS Based Voltage References. (Thesis). VTT Technical Research Centre of Finland. Retrieved from http://lib.tkk.fi/Diss/2006/isbn9513868605/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Kärkkäinen, Anna-Maija. “MEMS Based Voltage References.” 2006. Thesis, VTT Technical Research Centre of Finland. Accessed April 22, 2021. http://lib.tkk.fi/Diss/2006/isbn9513868605/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Kärkkäinen, Anna-Maija. “MEMS Based Voltage References.” 2006. Web. 22 Apr 2021.

Vancouver:

Kärkkäinen A. MEMS Based Voltage References. [Internet] [Thesis]. VTT Technical Research Centre of Finland; 2006. [cited 2021 Apr 22]. Available from: http://lib.tkk.fi/Diss/2006/isbn9513868605/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Kärkkäinen A. MEMS Based Voltage References. [Thesis]. VTT Technical Research Centre of Finland; 2006. Available from: http://lib.tkk.fi/Diss/2006/isbn9513868605/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

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