Publications

Crystal-Free Wireless Communication with Relaxation Oscillators and its Applications

David C. Burnett
Kristofer S.J. Pister
Ali M. Niknejad
Lance J. Kriegsfeld
2019

For the last decade, the size of complete 2.4GHz wireless modules containing everythingbut power have stagnated at ~1cm x 1cm. This is despite continued advances in semiconductorprocesses due to components needed by the core communication IC. Breaking this size barrier (which also sets a power and cost barrier) by eliminating all off-chip components is the goal of the Single-Chip Mote project, of which this dissertation is a part. The major componentsto be eliminated are antenna, battery, and crystal...

CMOS Based Chemical Sensors

Dharmesh Bhalchandra Jani
Kristofer S.J. Pister
1995
Detection of chemical species using solid state sensors is of great practical importance. The niche for chemical microsensors exists in places where continuous measurement of a chemical concentration is required from a number of locations. Microsensors...

Biochemical Microflow System / Microfabricated Optical Chopper

Michael T. Ching
Richard M. White
Albert P. Pisano
1993

The application of micromechanics to biochemical instrumentation yields many improvements in size, efficiency, and power consumption. The microdevices have small volumes which are compatible with many biochemical reactions. With the addition of integrated sensors, ...

Articulated Mechanisms and Electrostatic Actuators for Autonomous Microrobots

Richard Yeh
Kristofer S.J. Pister
Roger T. Howe
Dorian Liepmann
2001

Enabled by advances in both integrated circuit technology and micro electromechanical systems (MEMS), the continuing miniaturization and integration of electronics, sensors, and actuators and mechanisms will make it feasible to create insect-sized autonomous microrobots. We propose to create a class of autonomous crawling microrobots the size on the order f 1cm^3 and equipped with a power source, low-power CMOS controller, sensors, wireless communications devices and motorized articulated legs. The work presented here demonstrates how articulated insect legs could be created from rigid...

A CMOS Magnetic Sensor Chip for Biomedical Applications

Peng Liu
Bernhard E. Boser
Seth Sanders
Yuri Suzuki
2012

The growing need for pointofcare applications in global health and personalized medicine motivates a significant reduction in the size and cost of present technologies. Current solutions use fluorescent or enzymatic labels with complex optical instrumentation that has proven difficult to miniaturize. Recently, magnetic bead labeling has emerged as an alternative solution enabling portable and low...

A Micro-Electro-Mechanical Systems (MEMS) Device to Measure the Fracture Strain of Polycrystalline Silicon

Peter Truxtun Jones
Roger T. Howe
1995

The past decade has witnessed the establishment of a new field of technology concerned with the manufacture of microscopic sensors and actuators, known as Micro-Electro-Mechanical-Systems (MEMS). The field of MEMS is based on the use of integrated circuit fabrication techniques to create...

A MEMS Thin Film AlN Supercritical Carbon Dioxide Valve

Ya-Mei Chen
Albert P. Pisano
Liwei Lin
Tsu-Jae King Liu
Tarek Zohdi
2011
In this thesis, a new piezoelectric valve system with bi-chevron aluminum nitride (AlN) actuator is described. The intended application of the new piezoelectric valve is for the advanced printing technology with supercritical carbon dioxide as the solvent. With supercritical carbon dioxide as the solvent, the ink dissolved will start to nucleate with a micronozzle and generate extremely small and uniform ink particles due to rapid expansion of supercritical...

A Silicon-Based Microsensor to Measure Airborne Contaminants

Bharat M. Shah
Richard M. White
Albert P. Pisano
1994

In this reseach project the ability of a microfabricated acoustic-wave microsensor to detect volatile organic compounds in indoor air was studied. The microsensors were made in the Berkeley Microfabrication facility following designs developed at the Berkeley Sensor & Actuator Center. The devices were exposed in a four-liter chamber to vapor-phase concentrations of six representative VOCs one at a time: tetrachloroethylene, 1,1,1-trichloroethane, toluene, benzene, ethanol, and formaldehyde. The device sesnitivity to each VOC was computed from the measured oscillator frequency and...

A Multi-Stage Micro-Tangential Flow Filtration System for BioMEMS Applications

Patrick Pak-Ho Leung
Dorian Liepmann
Luke P. Lee
Liwei Lin
2002

The micromachining technology that emerged in the 1980s has yielded an explosion of developments of micro electromeclianica1 systems (MEMS) in the past two decades. The developments have brought lives to many miniaturized sensors and...

A MEMS Sensor for AC Electric Current

Eli Sidney Leland
Paul K. Wright
Richard M. White
Dennis K. Lieu
2009
This manuscript describes the development of a new MEMS sensor for the measurement of AC electric current. The sensor is comprised of a MEMS piezoelectric cantilever with a microscale permanent magnet mounted to the cantilever’s free end. When placed near a wire carrying AC current, the magnet couples to the oscillating magnetic field surrounding the wire, causing the cantilever to deflect, and piezoelectric coupling produces a sinusoidal voltage proportional to the current in the wire. The sensor is itself...