Publications

Polymer-Ceramic MEMS Bimorphs as Thermal Infrared Sensors

Clinton Warren
Albert P. Pisano
Luke P. Lee
Liwei Lin
2010
Thermal infrared detectors based on MEMS bimorph beams have the potential to exceed the performance of current uncooled thermal infrared cameras both in terms of sensitivity and cost. These cameras are part of a rapidly growing industry are used for a vast array of applications such as military and civilian night vision, industrial monitoring, and medical imaging. Many researchers have explored the use of metal-ceramic MEMS bimorphs...

The Design and Implementation of Parametrically Amplified Lorentz Force MEMS Magnetometers

Matt Thompson
David A. Horsley
Donald Margolis
Dean Karnopp
2010

This dissertation has two distinct goals. The first is to fabricate a MEMS Lorentz force navigation magnetometer using the same techniques as gyroscopes and accelerometers allowing for construction of a single ...

Cortical Microstimulation for Neural Prostheses

Subramaniam Venkatraman
Kristofer S.J. Pister
2010

Brain-controlled prostheses have the potential to improve the quality of life of a large num- ber of paralyzed persons by allowing them to control prosthetic limbs simply by thought. An essential requirement for natural use of such neural prostheses is that the user should be provided with somatosensory feedback from the artificial limb. This can be achieved by electrically stimulating small populations of neurons in the cortex; a process known as cor- tical microstimulation. This dissertation describes the development of novel technologies for experimental neuroscience and their use...

Oxygen Concentration Microgradients for Cell Culture

Jaehyun Park
Michel M. Maharbiz
Ming C. Wu
Amy E. Herr
2010

There is a growing need for technology that can control microscale oxygen gradients onto a tissue or culture sample in vitro. This dissertation introduces the oxygen microgradient chip (OMA), which employs electrolysis to generate oxygen microgradients within cell culture without forming bubbles. Dissolved oxygen generated at noble microelectrodes patterned on a chip surface diffuses through a gas-permeable silicone membrane and is dosed into cell culture. The amount of generated oxygen is directly proportional to a current flowing across the electrodes and thus can be controlled...

Fully Integrated Complementary Metal Oxide Semiconductor (CMOS) Bio-Assay Platform

Octavian Florescu
Bernhard E. Boser
Richard M. White
Ali Javey
Eva Harris
2010

We present a post-processed 6.25mm2 0.18μm Complementary Metal Oxide Semiconductor (CMOS) platform that leverages the advantages of super-paramagnetic bead labeling to integrate on-chip the label separation and detection functionalities required for high sensitivity bio-assays. The surfaces of the CMOS chip and of the magnetic beads are functionalized with bio-chemicals complementary to a target analyte. In a sandwich capture format, the presence of the target analyte will strongly bind 4.5μm magnetic bead labels to the...

An Experimental Study of Enhanced Thermal Conductivity Utilizing Columnated Silicon Microevaporators for Convective Boiling Heat Transfer at the Microscale

Christopher Hogue
Albert P. Pisano
Dorian Liepmann
Ming Gu
2011

In this work, siliconbased twolayer microfluidic evaporators were designed, fabricated, and tested in an experimental study designed to examine the effects of outofplane vaporization and subsequent lateral convection on the effective inplane thermal conductivity of the device. The evaporator region in all devices measured 10 mm x 10mm, with an overall device size of 24...

Light-induced Electrokinetics: A path to a Versatile Micro Total Analysis System

Justin Valley
Ming C. Wu
Michel M. Maharbiz
Amy E. Herr
2011

The micro total analysis system (uTAS) has seen great interest and advances since its definition over two decades ago. By harnessing the fabrication tools of the semiconductor industry and exploiting the unique physical phenomena that dominate at the micro- to nano-scale, these devices aim to address applications ranging from point-of-care diagnostics to pharmaceutical development. A truly versatile uTAS technology platform will enable reconfigurable, parallel, and high resolution analysis, processing, and sorting/purification. To this end, we present the concept of light-induced...

Towards a Synthesizable Standard-Cell Radio

Richard Su
Kristofer S.J. Pister
Jan Rabaey
Paul Wright
2011

Radios available today are designed to be high performance devices. These radios require careful design by experienced and skilled RF IC designers, more expensive RF processes, and large chip areas for RF passives. The resulting cost of these devices is at the dollar level without the off chip components, and the careful design required makes integration of these radios with other circuits (microprocessors, sensors, etc) an expensive proposition. We believe that radios that require limited design skills while still having good performance will enable widespread use of wireless...

High-Q Low-Impedance MEMS Resonators

Li-Wen Hung
Clark T.-C. Nguyen
Tsu-Jae King Liu
Liwei Lin
2012

The ever increasing need for regional and global roaming together with continuous advances in wireless communication standards continue to push future transceivers towards an ability to support multi-mode operation with minimal increases in cost, hardware complexity, and power consumption. RF channel-select filter banks pose a particularly attractive method for achieving multiband reconfigurability, since they not only provide the needed front-end reconfigurability, but also allow for power efficient and versatile transceiver designs, e.g., software-defined radio. Such channel-select...

Atomically Thin Processing of High Surface Area Nanomaterials for Electrochemical Energy Devices

Emmeline Kao
Liwei Lin
Hayden Taylor
Dorian Liepmann
2018

As interest in renewable energy grows on both research and policy fronts, energy storage likely represents one of the most viable solutions to the problems posed by the intermittency and irregularity of renewable resources. While new classes of materials promise improved performance of energy storage systems, understanding energy storage electrode architecture and fabrication at the micro-scale allows us to fully leverage performance along different dimensions.

This dissertation aims to explore the...