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Thesis (Elec.E)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1982., MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING, Includes bibliographical references., by Huan Lim Lee., Elec.E

Thesis (Elec.E)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1982., MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING, Includes bibliographical references., by Huan Lim Lee., Elec.E

Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000., Includes bibliographical references (leaves 34-35)., by Alicia M. Volpicelli., S.B.and M.Eng.

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1999., Includes bibliographical references (p. 165-172)., by Yao-Joe Yang., Ph.D.

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1999., Includes bibliographical references (p. 165-172)., by Yao-Joe Yang., Ph.D.

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1999., Includes bibliographical references (p. 165-172)., by Yao-Joe Yang., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1990., Includes bibliographical references (leaves 207-211)., by Joseph Barry Bernstein., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1990., Includes bibliographical references (leaves 207-211)., by Joseph Barry Bernstein., Ph.D.

Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998., Includes bibliographical references (leaf 29)., by Michael Hopgood., S.B.and M.Eng.

Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998., Includes bibliographical references (leaf 29)., by Michael Hopgood., S.B.and M.Eng.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998., Includes bibliographical references (p. 67-70)., by Joseph Y.-J. Young., M.S.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering; and, (S.M.)--Massachusetts Institute of Technology, Sloan School of Management, 2002., Includes bibliographical references (p. 64-65)., MEMS (Micro-Electronic Mechanical Systems) is an emerging and promising technology. It offers the promise of unique competitive advantages to companies able master the difficulties associated with it. One of those difficulties is manufacturing. Each new product poses a very unique fabrication challenge. The development of the fabrication process has to go hand in hand with the development of the product itself, and sometimes even drives it. ABB has identified MEMS technologies as a platform to improve its product line. It is currently developing a series of new products that will be enabled by MEMS. It has decided to outsource most if not all of the fabrication of its components. This presents it with a series of challenges related to the design and management of the associated supply-chain. This thesis focuses on the challenges faced by ABB in this journey. More specifically, the thesis will: ** Give a brief description of the efforts at ABB to incorporate MEMS technologies into their product portfolio; ** Report on the work done to survey the existing vendor pool for process competencies and to develop methods to find matches with ABB product needs; ** Describe the development of a database to anchor ABB's MEMS knowledge base; ** Analyze and describe the tactical options open for ABB in the design of its Supply Chain for MEMS Manufacturing; ** Identify the factors for success and the potential pitfalls going forward for ABB., by Rodrigo Sanchez., S.M.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering; and, (S.M.)--Massachusetts Institute of Technology, Sloan School of Management, 2002., Includes bibliographical references (p. 64-65)., MEMS (Micro-Electronic Mechanical Systems) is an emerging and promising technology. It offers the promise of unique competitive advantages to companies able master the difficulties associated with it. One of those difficulties is manufacturing. Each new product poses a very unique fabrication challenge. The development of the fabrication process has to go hand in hand with the development of the product itself, and sometimes even drives it. ABB has identified MEMS technologies as a platform to improve its product line. It is currently developing a series of new products that will be enabled by MEMS. It has decided to outsource most if not all of the fabrication of its components. This presents it with a series of challenges related to the design and management of the associated supply-chain. This thesis focuses on the challenges faced by ABB in this journey. More specifically, the thesis will: ** Give a brief description of the efforts at ABB to incorporate MEMS technologies into their product portfolio; ** Report on the work done to survey the existing vendor pool for process competencies and to develop methods to find matches with ABB product needs; ** Describe the development of a database to anchor ABB's MEMS knowledge base; ** Analyze and describe the tactical options open for ABB in the design of its Supply Chain for MEMS Manufacturing; ** Identify the factors for success and the potential pitfalls going forward for ABB., by Rodrigo Sanchez., S.M.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998., Includes bibliographical references (p. 67-70)., by Joseph Y.-J. Young., M.S.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering; and, (S.M.)--Massachusetts Institute of Technology, Sloan School of Management, 2002., Includes bibliographical references (p. 64-65)., MEMS (Micro-Electronic Mechanical Systems) is an emerging and promising technology. It offers the promise of unique competitive advantages to companies able master the difficulties associated with it. One of those difficulties is manufacturing. Each new product poses a very unique fabrication challenge. The development of the fabrication process has to go hand in hand with the development of the product itself, and sometimes even drives it. ABB has identified MEMS technologies as a platform to improve its product line. It is currently developing a series of new products that will be enabled by MEMS. It has decided to outsource most if not all of the fabrication of its components. This presents it with a series of challenges related to the design and management of the associated supply-chain. This thesis focuses on the challenges faced by ABB in this journey. More specifically, the thesis will: ** Give a brief description of the efforts at ABB to incorporate MEMS technologies into their product portfolio; ** Report on the work done to survey the existing vendor pool for process competencies and to develop methods to find matches with ABB product needs; ** Describe the development of a database to anchor ABB's MEMS knowledge base; ** Analyze and describe the tactical options open for ABB in the design of its Supply Chain for MEMS Manufacturing; ** Identify the factors for success and the potential pitfalls going forward for ABB., by Rodrigo Sanchez., S.M.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998., Includes bibliographical references (p. 67-70)., by Joseph Y.-J. Young., M.S.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering; and, (S.M.)--Massachusetts Institute of Technology, Sloan School of Management, 2002., Includes bibliographical references (p. 64-65)., MEMS (Micro-Electronic Mechanical Systems) is an emerging and promising technology. It offers the promise of unique competitive advantages to companies able master the difficulties associated with it. One of those difficulties is manufacturing. Each new product poses a very unique fabrication challenge. The development of the fabrication process has to go hand in hand with the development of the product itself, and sometimes even drives it. ABB has identified MEMS technologies as a platform to improve its product line. It is currently developing a series of new products that will be enabled by MEMS. It has decided to outsource most if not all of the fabrication of its components. This presents it with a series of challenges related to the design and management of the associated supply-chain. This thesis focuses on the challenges faced by ABB in this journey. More specifically, the thesis will: ** Give a brief description of the efforts at ABB to incorporate MEMS technologies into their product portfolio; ** Report on the work done to survey the existing vendor pool for process competencies and to develop methods to find matches with ABB product needs; ** Describe the development of a database to anchor ABB's MEMS knowledge base; ** Analyze and describe the tactical options open for ABB in the design of its Supply Chain for MEMS Manufacturing; ** Identify the factors for success and the potential pitfalls going forward for ABB., by Rodrigo Sanchez., S.M.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998., Includes bibliographical references (p. 67-70)., by Joseph Y.-J. Young., M.S.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1994., Includes bibliographical references (leaves 194-202)., by Scott Anthony Sikorski., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1990., Includes bibliographical references (leaves 151-156)., by Mehran Mehregany., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, February 2002., Includes bibliographical references (p. 80-84)., The field of MEMS has matured significantly over the last two decades increasing in both complexity and level of integration. To keep up with the demands placed by these changes requires the development of computer-aided design and modeling tools (CAD/CAM) that enable designers to reduce the time and cost it takes to produce working prototypes. An ideal scenario is one in which a designer is able to quickly model and simulate an entire microsystem - sensors, actuators and electronics -- with the certainty that their results will match that of physical prototypes. This vision of design requires the existence of system level models of MEMS devices that can capture the complex non-linear coupling between multiple physical domains, yet be sufficiently fast and compact in form to insert into a system dynamics simulator. In this thesis I explore techniques of automatically constructing such models from meshed representations of device geometry. These dynamical models are known as "reduced-order" models or "macromodels." They are characterized by few degrees of freedom (DOF), and a small set of state equations. Our process for constructing macromodels is built upon two well-established methodologies - normal mode superposition and Lagrangian mechanics. This is referred to as the "CHURN process" and was originally developed by Gabbay et al. to create models of electromechanical devices with two electrodes under conditions satisfying linear mechanics., (cont.) In this thesis I significantly extend this process to model multi-port magnetostatic devices, multi-port electrostatic devices, and geometrically non-linear mechanical devices exhibiting stress stiffening. I also address one of the key concerns in building macromodels -- the required degree of sophistication, and the extent of involvement, of a designer in the model construction process. I propose and implement several heuristic techniques that automate the model generation process. I also apply these techniques to a fabricated microelectromechanical high frequency filter and present verification of our modeling results., by Matthew Varghese., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1995., Includes bibliographical references (leaves 140-143)., by Peter Maynard Osterberg., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2002., Includes bibliographical references., This thesis presents the nonlinear analysis, design, fabrication, and testing of an axial-gap magnetic induction micro machine, which is a two-phase planar motor in which the rotor is suspended above the stator via mechanical springs, or tethers. The micro motor is fabricated from thick layers of electroplated NiFe and copper, by our collaborators at Georgia Institute of Technology. The rotor and the stator cores are 4 mm in diameter each, and the entire motor is about 2 mm thick. During fabrication, SU-8 epoxy is used as a structural mold material for the electroplated cores. The tethers are designed to be compliant in the azimuthal direction, while preventing axial deflections and maintaining a constant air gap. This enables accurate measurements of deflections within the rotor plane via a computer microvision system. The small scale of the magnetic induction micro machine, in conjunction with the good thermal contact between its electroplated stator layers, ensures an isothermal device which can be cooled very effectively. Current densities over 109 A/m2 simultaneously through each phase is repeatedly achieved during experiments; this density is over two orders of magnitude larger than what can be achieved in conventional macro-scale machines. More than 5 Nm of torque is obtained for an air gap of about 5 zm, making this micro motor the highest torque density micro-scale magnetic machine to date. About 0.3 buNm for the large air gap of 70 m is also achieved in systematic tests that reveal the influence of strong eddy-currents and associated nonlinear saturation within the micro motor., (cont.) Eddy-current effects are modeled using a finite-difference vector potential formulation. Its results demonstrate the presence of flux crowding on the stator surface, which leads to heavy saturation. To capture saturation effects, a fully nonlinear finite-difference time-domain simulation is developed to solve Maxwell's Equations within the computational space of the micro machine. To mitigate the inherent stiffness in the partial differential equations, the speed of light is artificially reduced by five orders of magnitude, taking special care that assumptions of magnetoquasistatic behavior are still met. The results from this model are in very good agreement with experimental data from the tethered magnetic induction micro motor., by Hür KöÅŸer., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, February 2002., Includes bibliographical references (p. 80-84)., The field of MEMS has matured significantly over the last two decades increasing in both complexity and level of integration. To keep up with the demands placed by these changes requires the development of computer-aided design and modeling tools (CAD/CAM) that enable designers to reduce the time and cost it takes to produce working prototypes. An ideal scenario is one in which a designer is able to quickly model and simulate an entire microsystem - sensors, actuators and electronics -- with the certainty that their results will match that of physical prototypes. This vision of design requires the existence of system level models of MEMS devices that can capture the complex non-linear coupling between multiple physical domains, yet be sufficiently fast and compact in form to insert into a system dynamics simulator. In this thesis I explore techniques of automatically constructing such models from meshed representations of device geometry. These dynamical models are known as "reduced-order" models or "macromodels." They are characterized by few degrees of freedom (DOF), and a small set of state equations. Our process for constructing macromodels is built upon two well-established methodologies - normal mode superposition and Lagrangian mechanics. This is referred to as the "CHURN process" and was originally developed by Gabbay et al. to create models of electromechanical devices with two electrodes under conditions satisfying linear mechanics., (cont.) In this thesis I significantly extend this process to model multi-port magnetostatic devices, multi-port electrostatic devices, and geometrically non-linear mechanical devices exhibiting stress stiffening. I also address one of the key concerns in building macromodels -- the required degree of sophistication, and the extent of involvement, of a designer in the model construction process. I propose and implement several heuristic techniques that automate the model generation process. I also apply these techniques to a fabricated microelectromechanical high frequency filter and present verification of our modeling results., by Matthew Varghese., Ph.D.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1981., MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING., Includes bibliographical references., by Ralph Benhart Iverson., M.S.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1980., MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING., Includes bibliographical references., by Steven Lee Garverick., M.S.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1985., MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING., Includes bibliographical references., by Michael Christian Wohnsen Coln., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1990., Includes bibliographical references (leaves 151-156)., by Mehran Mehregany., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1994., Includes bibliographical references (leaves 142-149)., by Albert Min-Hsien Young., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997., Includes bibliographical references (leaves 59-64)., by Raj K. Gupta., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1992., Includes bibliographical references (leaves 109-116)., by Jeffrey Yen Pan., Ph.D.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998., Includes bibliographical references (leaves 45-46)., by Erik R. Deutsch., M.S.

Massachusetts Institute of Technology. Dept. of Electrical Engineering. Thesis. 1974. Elec.E., MICROFICHE COPY ALSO AVAILABLE IN BARKER ENGINEERING LIBRARY., Includes bibliographical footnotes., Elec.E.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1992., Includes bibliographical references (leaves 214-222)., by Susan Cunningham Noe., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 1989., Includes bibliographical references (leaves 224-229)., by Herbert John Neuhaus., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1994., Includes bibliographical references (leaves 194-202)., by Scott Anthony Sikorski., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1992., Includes bibliographical references (leaves 214-222)., by Susan Cunningham Noe., Ph.D.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1981., MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING., Includes bibliographical references., by Ralph Benhart Iverson., M.S.

Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001., Includes bibliographical references (leaves 56-57)., With the growing use of microelectromechanical systems (MEMS), it becomes increasingly important that reliable, accurate methods for characterizing and calibrating MEMS be developed. One microsystem in need of specific characterization measurements is the polychromator, an electrically programmable, surface micromachined diffraction grating. A microvision system has been developed to measure the electromechanical behavior of the polysilicon beams that comprise this device. Proper rigor demands that the system for making characterizations should itself be characterized; its accuracy and precision should be determined, so that users may understand the possible error margins of its measurements. This thesis describes HUMS (Heavily Upsampling Microvision System), the software application developed to automate the characterization of the polychromator, and the method developed to quantify the accuracy of the HUMS application., by Jaydeep Porter Bardhan., M.Eng.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1994., Includes bibliographical references (leaves 194-202)., by Scott Anthony Sikorski., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1992., Includes bibliographical references (leaves 214-222)., by Susan Cunningham Noe., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1990., Includes bibliographic references (leaves 174-179)., by Pinyen Lin., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 1989., Includes bibliographical references (leaves 188-193)., by Mark George Allen., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 1989., Includes bibliographical references (leaves 188-193)., by Mark George Allen., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998., Includes bibliographical references (leaves 99-107)., This thesis describes work on incorporating electrostatically-actuated microstructures for analog tuning and positioning applications within optical and RF systems. The work focuses on the design, simulation, and optimization of actuators which undergo large-amplitude motion, including ways to overcome the so-called pull-in instabil­ity which typically limits the stable travel distance of electrostatic actuators. These techniques are applied to the design and fabrication of: (1) the polychromator, a micromcchanical diffraction grating with a thonsand analog-positioned mirrors for use in a correlation spectroscopy system, and (2) a tunable capacitance device with a lithographically-programmable capacitance-voltage (C-V) characteristic for use in tunable RF oscillators. With the polychromator, 1 cm long electrostatic mirror actua­tors have achieved over 1. 75µm of displacement out of a 2[mu]m gap. Prototype tunable capacitors fabricated in a non-optimized process exhibit a 25% capacitance tuning range with a linear C-V characteristic and 35V actuation voltage. With an optimized process, simulations show that a 150% capacitive tuning range can ht: achieved with 3.3V actuation voltage. The integration of micromechanical devices into complex, mixed technology sys­tems also requires methods for efficiently simulating the dynamics of micromcchani­cal devices. We present work on generating efficient reduced-order macromodels for simulating the dynamics of micromechanical devices by extracting global basis func­tions using information from a few runs of a computationally expensive finite element. model. Using a squeeze-film air-damped, electrostatically-actuated beam as an ex-­ample, a macromodel with 2 pressure and 2 displacement basis functions achieves less than 2% error and a factor of 37 increase in efficiency compared to meshed simulation techniques along with good correspondence to experimental data., by Elmer S. Hung., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2002., Includes bibliographical references (p. 77-80)., This thesis describes electrostatic actuation techniques and mechanical design features for realizing large planar analog vertical travel in an electrostatically actuated diffractive mid-infrared optical device, which is robust, both to manufacture, and against pull-in during use. This device, called the Polychromator, is fabricated by polysilicon surface-micromachining and consists of many parallel elements, each 20 microns wide and a centimeter in length. Typically, achieving such a large travel would require prohibitively large gaps and actuation voltages. In order to reduce the actuation voltage and achieve greater travel before pull-in, thinner beams are used which exploit stress stiffening. This, in turn, creates a number of stress control hazards because tensile stress in one layer can induce buckling in a lower layer. These issues have been solved with detailed attention to supports and their compliance. A multi-layer nonlinear spring has been incorporated to make the device robust against pull-in. The electromechanical behavior of the device is simulated using Energy Methods, Finite Difference Methods, and the MEMCAD software. Excellent agreement between MEMCAD simulation and experimental measurements for this structure are reported. Each detail, stress control, support structure, and pull-in, must be addressed in order to achieve the combined effects of large travel, robustness against pull-in, and optically flat beams., (cont.) Controlled planar actuation over a large vertical range at low applied voltages is obtained by combining a robust electromechanical design with a manufacturable surface micromachining process. Covering a centimeter square area, the 512 grating elements achieved 3.8 microns vertical displacement at 72 Volts with a 0.5 Volt standard deviation, indicating uniform performance across the device. The development of the device has led to innovations in position control, fabrication processes, device design, and device testing., by Erik R. Deutsch., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1985., MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING., Includes bibliographical references., by Michael Christian Wohnsen Coln., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1992., Includes bibliographical references (leaves 109-116)., by Jeffrey Yen Pan., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1988., Bibliography: leaves 180-185., by Martin Arnold Schmidt., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1995., Includes bibliographical references (leaves 140-143)., by Peter Maynard Osterberg., Ph.D.