Publications

Lab-on-a-Chip Mechanical and Optical Components

Nikolas Chronis
Luke P. Lee
Lisa Pruitt
Albert P. Pisano
Richard S. Muller
2004
The present work aims to provide new tools for the manipulation and detection of biological samples. They can be envisioned as individual components of an integrated, lab-on-a-chip system. A novel SU-8 microgripper is introduced for the manipulation of single cells or other biological species in solution with minimal undesired interactions. The electrothermally activated polymer gripper consists of two SU-8 ‘hot-and-cold-arm’ actuators that are fabricated in a two-mask...

Capacitive Power Transfer

Mitchell Kline
Bernhard E. Boser
Seth R. Sanders
2011

The simplicity and low cost of capacitive interfaces makes them very attractivefor wireless charging stations and galvanically isolated power supplies. Major benefits include low electromagnetic radiation and the amenability of combined power and data transfer over the same interface.

We present a capacitive power transfer circuit using series resonance that enables efficient high frequency, moderate voltage operation through soft-switching. An included analysis predicts fundamental limitations on...

Micromachined Dual Input Axis Rate Gyroscope

Thor Juneau
Albert P. Pisano
Roger T. Howe
Roberto Horowitz
1997
The need for inexpensive yet reliable angular rate senors in fields ranging from automotive to consumer electronics has motivated prolific micromachined rate gyroscope research. The vast majority of research has focused on single input axis rate gyroscopes based upon either translational resonance, such as tuning forks, or...

Design, Theory, and Applications of Integrable Carrier-Domain Magnetometers

Juan Goicolea
Richard S. Muller
1986
This thesis describes an integrated silicon vertical geometry carrier-domain magnetometer fabricated on a silicon substrate using a commercial linear bipolar process. It also describes several chips in which CDMs are used in conjunction with other cir...

Polycrystalline Silicon-Germanium Films for Integrated Microsystems

Andrea Franke
Tsu-Jae King
Roger T. Howe
Timothy Sands
2000

Poly cystalline silicon (poly-Si) and silicon dioxide (SiO2) are the standard strucutral and sacrifical materials in surface micromachines MEMS. Polycrystalline silicon-germanium (poly-SiGe) can be deposited in a standard LPCVD furnace at much lower temperatures (less than or equal to 450degC) than poly-Si. This allows integration of poly-SiGe MEMS after completion of a CMOS process with Al or Cu interconnects. Modularly integrating MEMS onto wafers with standard CMOS circuits reduces parasitics, increases packaging simplicity and reliability, could lower processing cost, allows for...

Energy Measures for Sensor Networks

Lance Doherty
Kristofer S.J. Pister
Kannan Ramchandran
Ming Gu
2004
The problem of full data recovery from a sensor network of thousands of randomlyplaced nodes is addressed as it relates to the complexity of the network data. In the applications of interest, the user requires a representation of the full twodimensional data generated by a field underlying the area of the network. The usefulness of data recovery algorithms is judged by the units of energy consumption to recover sufficient data to reconstruct the field to a...

Electro Micro-Metrology

Jason Clark
Kristofer S. J. Pister
James Demmel
Sanjay Govindje
Luke P. Lee
2005
Electro Micro-Metrology (EMM) is a novel methodology for precision metrology, sensing, and actuation at the micro- and nano-scale. EMM is well-suited for tiny technology because it leverages off the electromechanical benefits of the scale. EMM is the method of using micro- or nano-scale devices to measure and characterize themselves, other devices, or whatever the devices subsequently interact with. By electronically measuring the change in capacitance, change in voltage, and/or resonant frequency of just a...

Devices, Structures, and Processes for Optical MEMS

Hyuck Choo
Richard S. Muller
Jeffrey Bokor
James R. Graham
2007

High-precision microlenses have been fabricated utilizing hydrophobic effects and polymer-jet printing technology. The lenses are formed precisely at desired locations on a wafer using a polymer-jet system in which hydrophobic effects define the lens diameter and surface tension creates a high-quality optical surface. They have 200–1000-μm diameters and 343–7862-μm focal lengths. At 635 nm, wavefront aberrations (measured using a Shack-Hartmann sensor of λ/100 accuracy) are λ/5-...

Surface Engineering for MEMS Reliability

William Ashurst
Roya Maboudian
David B. Graves
Roger T. Howe
2003

The integration of miniaturized mechanical components with microelectronic components has spawned a new technology known as microelectromechanical systems (MEMS). This technology extends the benefits of microelectronic fabrication to sensing and actuating functions. Examples of MEMS devices that have been commercially produced include relatively simple mechanisms such as accelerometers, pressure sensors and digital mirror projectors.

Despite recent progress in micromachining capability, the realization of more complex commercial and specialized use of MEMS is challenged due to...

Actively Variable-Spectrum Optoelectronics with Black Phosphorus

Hyungjin Kim
Shiekh Zia Uddin
Der-Hsien Lien
Matthew Yeh
Nima Sefidmooye Azar
Sivacarendran Balendhran
Taehun Kim
Niharika Gupta
Yoonsoo Rho
Costas P. Grigoropoulos
Kenneth B. Crozier
Ali Javey
2021

Room-temperature optoelectronic devices that operate at short-wavelength and mid-wavelength infrared ranges (one to eight micrometres) can be used for numerous applications. To achieve the range of operating wavelengths needed for a given application, a combination of materials with different bandgaps (for example, superlattices or heterostructures) or variations in the composition of semiconductor alloys during growth are used. However, these materials are complex to fabricate, and the operating range is fixed after fabrication. Although wide-range, active and reversible tunability...