Publications

High electron mobility III-V compound semiconductors such as indium arsenide (InAs) are promising candidates for future active channel materials of electron devices to further enhance device performance. In particular, compound semiconductors heterogeneously integrated on Si substrates have been studied, combining the high mobility of III-V semiconductors and the well-established, low cost processing of Si technology. However, one of the primary challenges of III-V device fabrication is controllable, post-growth dopant profiling. Here InAs nanowires and ultrathin layers (nanoribbons...

Electrocorticography (ECoG) has been used for decades clinically to help localize epileptic seizures but has only recently come into vogue as a potentially useful imaging modality. This change has partially been driven by the development of new micro-electrocorticography (µECoG) arrays which take advantage of modern surface micromachining techniques to achieve extremely dense electrode arrays packed with tiny (less than500µm diameter) electrodes. As an imaging tool, µECoG may be improved by taking advantage of the transparent µECoG array technology developed at the University of...

In order to create a low-power and lightweight wireless sensor node for the control of MEMS microrobots, the Single Chip Mote project aspires to integrate a fully-functioning microprocessor, radio, sensors, and solar cells onto a single die, while also eliminating the need for external components through careful architectural design. This report presents the past two years of work on the design of the Single Chip Mote digital system, complete with an ARM Cortex-M0 microprocessor, control logic for an IEEE 802.15.4 radio, special-purpose radio timers, and ADC interface. This includes...

Vacuum encapsulation of RF disk and beam resonators is often needed to maintain high quality factor and frequency stability. Conventionally, this is performed at the wafer level by anodic, eutectic, fusion, or glass frit bonding. After wafer dicing, packaging proceeds with die attach to the package substrate and plastic over molding. This process leads to many contacts between materials of different coefficients of thermal expansion (CTE) resulting in package-induced stress. The focus of this work is to determine the effect of this stress on the temperature stability of...