Publications

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 ...

Microfabricated Electrostatic Actuators for Magnetic Disk Drives

David A. Horsley
Albert P. Pisano
Roberto Horowitz
Roger T. Howe
1998
This dissertation describes microfabricated electrostatic actuators which have been designed to serve as the secondary actuator in a dual-stage servo system for magnetic hard disk drives. Both translational and rotational designs are presented, each of which consists of a flexurally suspended ...

An Integrated MEMS Syringe for Advanced Drug Delivery: Design, Fabrication and Fluid Mechanics of Suspension Flow through Microneedle Arrays

Boris Stoeber
Dorian Liepmann
Albert P. Pisano
Luke P. Lee
2002

New approaches for drug delivery seek to enable improved patient comfort as well as to provide an improved level of care. New approaches are especially important for drugs that cannot be administered orally. Liquid and lyophilized drugs can be delivered under the stratum corneum because of rapid diffusion of the drug into the capillary bed under the skin.

For this purpose, a syringe has been developed and fabricated using microfabrication to make an array of hollow, out-of-plane silicon needles using a combination of DRIE and isotropic etching. The needles have a typical height of...

Micromachined Resonators

Dubravka Bilić
Roger T. Howe
Kristofer S. J. Pister
Roberto Horowitz
2001

In this work, we present approaches of making a micromachined resonators and oscillators. In the first study, we investigated the effects of anchoring on the resonator's performance. Using the Analog Devices BiMEMS integrated technology, double-ended tuning fork resonators have been fabricated with on-chip circuitry. The results show an improvement in the resonator's quality factor when using anchors with multiple contacts to the substrate. Resonators with frequencies up to 3MHz were tested at µTorr pressures to give quality factors as high as 58,000.

In order to reduce...

Miniature-Scale and Micro-Scale Rotary Internal Combustion Engines for Portable Power Systems

Kelvin Fu
A. Carlos Fernandez-Pello
Albert P. Pisano
Kristofer J. Pister
Dorian Liepmann
2001

This work describes the development of both miniature-scale and micro-scale rotary internal combustion engines. This work is part of a project to develop a portable, high specific energy, liquid hydrocarbon-fueled power supply. A Wankel-type rotary engine was chosen for development because of its self-valving operation, planar geometry, and the ability to extract either mechanical or electrical power. To investigate engine behavior and design issues, larger-scale "mini-rotary'' engines have been fabricated from 4 steel. Mini-rotary engine chambers are approximately 1000 mm3 to 1 700 mm3 in...

Capacitive Position-Sensing Interface for Micromachined Inertial Sensors

Xuesong Jiang
Bernhard E. Boser
Roger T. Howe
Roberto Horowitz
2003

A monolithic MEMS/circuits technology enables the implementation of multiple sensors and more functions, such as sensing, signal processing and actuation, on a single chip. In this work, issues related to monolithic integration of micromachined inertial sensors, including accelerometers and gyroscopes, are investigated. Mechanical sensitivity, noise, and experimental performance verification of the open-loop accelerometer are discussed. The resolution of a position-sensing accelerometer can be improved by increasing the mechanical sensitivity and the accuracy of position measurement. 1¹G=...