Publications

Miniature Gaseous Light Sources

Hsi-Jen Yeh
Richard S. Muller
Roger T. Howe
1991

This report describes miniature gas-filled plasma-discharge cavities fabricated using combined surface and subsurface micromachining. Starting with a bare silicon substrate, successive layers of polycrystalline silicon, low-stress silicon nitride, and low-temperature oxide layers were deposited to form the micro cavities. Polysilicon electrodes were patterned to serve as electrical connections to the gas. Low-stress silicon nitride formed the insulating layer and the cavity wall which confined neon at atmospheric pressure. Low-temperature oxide served as the sacrificial layer which defined...

Microstructure Micropackaging

Kristen M. McNair
Roger T. Howe
Richard M. White
1991

Two processes are developed to fabricate electrostatic comb drives hermetically encapsualted in a silicon nitride or polysilicon micropackage. To fabricate the silicon nitride micropackage, high-doped phosphosilicate glass is deposited, after the electrostatic comb-drive process is complete except for the release etch, and reflowed to form a mould for the silicon nitride microshell. The mould is patterned with a 5:1 BHF wet etch, and then the etch channel layer of phosphosilicate glass is deposited and patterned with a wt etch. The silicon nitride microshell layer is depositied, and holes...

Micromechanical Electrostatic Voltmeter

Charles Heng-Yuan Hsu
Richard S. Muller
Roger T. Howe
1991

A microminiature, noncontracting electrostatic voltmeter (ESV), produced by IC processes on a silicon wafer, is described. The ESV works on the principle of intermittent shuttering and exposing a sensing electrode to an electric field between a remote electrode at a different potential from the sensing electrode. The resultant time-varying field at the electrode produces an electrical signal. The principle of ESV measurements by intermittent shuttering is well establihsed and hybrid designs are presently used commerically. This invention teaches how the entire structure, and eventually the...

Growth Stresses in Undoped LPCVD Polycrystalline Silicon Films

Peter Krulevitch
1991
Thin films have applications in many technological fields, particularly in the area of electronics, where they form the basis of integrated circuits [l]. More recently, the techniques used to manufacture VLSI circuits have been applied to mechanical systems, such as...

Analysis and Characterization of the Vertical Carrier Domain Magnetometer

Bret S. Burns
Richard S. Muller
Roger T. Howe
1989
The point of semiconductor device analysis is to find useful predictors of device performance. With these we can design to specifications, uncover promising directions for improving device operation, and understand device limitations. An actual device has no...

Polysilicon Microstructures to Characterize State Friction

Martin Lim
Roger T. Howe
Roberto Horowitz
1990

A polysilicon microstucture to characterize static fiction has been developed. A normal force is applied to a displaced suspended structure by an underlying electrode. The tangential force to measure the frictional force is produced by a...

A Tactile Sensor Utilizing Light Coupling Between Optical Fibers

Vadim Konradi
1987

A tactile sensing array emplying optical fibers has been constructed and tested. The sensor is composed of two layers of optical fibers, oriented at right angles to each other, and overlaid by an elastomer sheet. Fibers in the upper layer are illuminated individually. Total internal reflection is violated by pressure-induced contact between the elastomer and the upper fiber layer. Scattered light is collected by fibers in the lower layer, resultin gin a matrix of tactile pressure readings.

The sensor concept was verified, and recognizable tactile images were generated for simple...

Gimballed Electrostatic Microactuators with Embedded Interconnects

Lilac Muller
Albert P. Pisano
Roger T. Howe
Kristofer S.J. Pister
2005
A microgimbal with an integrated in-plane electrostatic microactuator was designed, fabricated, and tested. The microgimbal structure provided pitch and roll compliance between the microactuator and ground, and thus offered mechanical isolation from external disturbances, such as vibration and temperature variations. ...

Hinged Polysilicon Structures with Integrated CMOS Thin Film Transistors

Kristofer S.J. Pister
Roger T. Howe
1992
Before Micro Electro Mechanical &stems (MEMS) can achieve their full potential, design tools for these systems must be made available to members of other disciplines, and not restricted only to those with the...

Micromechanical Power Conversion

J. Mark Noworolski
Seth Sanders
Roger T. Howe
Albert P. Pisano
1998

A new concept in power conversion, based on electromechanical energy storage, is developed. Mechanical energy storage using Silicon offers a 2 order of magnitude improvement in volumetric energy storage density over conventional approaches using...