Publications

Optical MEMS for Free-Space Communication

Lixia Zhou
Kristofer S.J. Pister
Joseph M. Kahn
Roger T. Howe
Alice M. Agogino
2004
The convergence of MEMS technology with communication and digital circuitry makes high-speed, low power, free-space communication links over distances up to several km possible. MEMS corner cube retroreflectors (CCRs) are proposed to work as a passive optical transmitter, sending collected information back to an interrogating center. MEMS scanning microm...

Water-Powered Microfluidic Devices for Diagnostic and Drug Delivery Systems

Yu-Chuan Su
Liwei Lin
Albert P. Pisano
Luke P. Lee
2003
This dissertation presents the development of water-powered microfluidic devices, including actuators, pumps, pressure-sensitive valves, and flow discretizers, by integrating osmosis, capillarity, microfabrication, and polymer processing technologies at the microscale. By harvesting and coordinating the mechanical actuations driven by chemical potentials and interfacial forces, these water-powered devices can transport flows in pre-...

Electromagnetic Effects in MEMS Application: Actuators, Relay and Packaging

Andrew Cao
Liwei Lin
Albert P. Pisano
Luke P. Lee
2004
Two electromagnetic effects are utilized in MEMS applications: electromagnetic Lorentz force for bidirectional actuator/relay operations, and electromagnetic induction heating for MEMS bonding and packaging processes. As a proofofconcept demonstration, a liquidmetal wetted contact process is developed to reduce the contact resistance in MEMS relay applications. Electromagnetic Lorenz force is utilized to control the actuation direction of bi...

Electromagnetic Generators for Portable Power Applications

Matthew Kurt Senesky
Seth R. Sanders
Albert P. Pisano
Dennis K. Lieu
2005
The power source that is common to almost all electrically powered portable devices— the electrochemical battery — has failed to shrink at the same rate as circuits and sensors. While this growing disparity has been partially mitigated by the decreasing power requirements of many electronic circuits, the size and weight of portable electronic devices are increasingly dominated by electrochemical batteries. An obvious set of candidates for energy storage with...

MEMS Microbial Fuel Cells and Photosynthetic Electrochemical Cells

Kien-Bang Lam
Liwei Lin
Albert P. Pisano
Kevin E. Healy
2005
In this dissertation, we present three MEMS (Micro-electro-mechanical Systems) biological electrochemical cells: (1) a microbial fuel cell (μMFC) utilizing glucose as the bio-fuel and live baker’s yeast as the bio-catalyst; (2) a photosynthetic electrochemical cell (μPEC1) based on unicellular bacteria Anabaena as the biological photo-electrical converter; and (3) a second photosynthetic electrochemical cell (μPEC2)...

Silicon Processed Microstructures Using Self-Aligned Plastic Deformation

Jongbaeg Kim
Liwei Lin
Albert P. Pisano
Luke P. Lee
2004

Two self-aligend plastic deformation processes are devleoped to fabricate silicon microstructures, including angular vertical comb-drives, scanning micromirrors, variable capacitors, and two-axial actuators based on global-furnace and localized-Joule heating methods. As a proof-of-concept demonstration, an ultrasonic packaging procedure that generates local plastic deformation of metallic bonding materials is also established for MEMS packaging applications.

Plastic defomation of silicon occurs at elevated temperature when silicon is stresses to a level higher than the reduced yield...

Piezoelectric Aluminum Nitride Vibrating RF MEMS for Radio Front-End Technology

Gianluca Piazza
Albert P. Pisano
Roger T. Howe
Liwei Lin
Kristofer S.J. Pister
2005
The demand of consumer electronics for RF filters and frequency reference elements has focused attention on the reduction of size, power consumption and price and pushed current research interests towards the manufacturing of a single-chip, integrated RF solution. Vibrating contour-mode MEMS resonators constitute the most promising technology for ultimately realizing this vision. This dissertation presents analytical and experimental results on a new class...

Localized Synthesis, Assembly and Integration of Silicon Nanowires

Ongi Englander
Liwei Lin
Albert P. Pisano
Oscar D. Dubon
2005
Localized synthesis, assembly and integration of one-dimensional silicon nanowires with MEMS structures is demonstrated and characterized in terms of local synthesis processes, electric-field assisted self-assembly, and a proof-of-concept nanoelectromechanical system (NEMS) demonstration. Emphasis is placed on the ease of integration, process control strategies, characterization techniques and the pursuit of integrated devices. A top-down followed by a...

Fabrication of Exposed Gate Field Effect Transistors for Sensor Applications

Albert William Flounders
Dennis W. Hess
1992

A dual dielectric structure was used as the gate insulating layer of an exposed gate field effect transistor in sensor applications. This structure, which consisted of thermally grown silicon dioxide and chemical vapor deposited (CVD) silicon nitride, provided elecmcal...

Microfabricated Silicon High Aspect Ratio Flexures for In-Plane Motion

Christopher Guild Keller
Roger T. Howe
John W. Morris, Jr.
Kristofer S.J. Pister
Timothy D. Sands
1998

High aspect ratio microfabricated silicon flexures for in-plane motion were made by three methods: (1) 2-sided timed bulk etching in aqueous potassium hydroxide (KOH), (2) deep reactive ion etching (RB) with Cl2/He, and with SF6 (Bosch process), and (3) the hexsil ...