Publications

The increasing demands for higher performance, advanced wireless and mobile communication systems have continuously driven device innovations and system improvements. In order to reduce power consumption and integration complexity, radio frequency (RF) microelectromechanical systems (MEMS) resonators and filters have been considered as direct replacements for off-chip passive components. In this dissertation, a new radio architecture for direct channel selection is explored. The primary elements in this new architecture include a multitude of closely-spaced narrowband filters (...

This dissertation presents a design methodology for on-chip magnetic bead label detectors based on Hall-effect sensors to be used for biosensor applications. Signal errors caused by the label-binding process and other factors that place constraints on the minimum detector area are quantified and adjusted to meet assay accuracy standards. The methodology is demonstrated by designing an 8,192 element Hall sensor array implemented in a commercial 0.18 μm CMOS process with single mask post-processing. The array can quantify a one percent surface coverage of 2.8 μm beads in thirty seconds...

Water shortages, particularly evident in the state of California, emphasize the need for a better hydrologic understanding, and improved water management techniques. The majority of the state’s water originates in the Sierra Nevada as snow, melting throughout the year to meet the needs of various stakeholders. Current measurement techniques are unable to resolve variability of the snowpack at the basin scale, and snowmelt processes are not well captured by existing hydrologic models. A system-level solution is introduced to facilitate scientific understanding and water management...

Nanostructures have unique properties that will be leveraged for next generation sensor and energy applications: large surface-to-volume ratios, increased sensitivity at lower input power levels, and higher current densities all contribute to increased functionality of nano- structure devices. The synthesis and integration of carbon-, metal-, and metal oxide-based nanostructures for sensor and energy applications are studied with the goal of nano-to-micro devices utilizing well-established micro- and nano-fabrication tools and techniques: (1) self- assembled, integrated carbon...