As information systems have evolved from isolated computational engines to distributed networks, the autonomous ability to gather and act on information is becoming increasingly important. My research is in the interdisciplinary area of MicroElectroMechanical Systems (MEMS): sensor and actuator systems with performance derived from integration of electronics and mechanical structures with features measured in microns to millimeters. Fabrication of the batch-fabricated electromechanical devices and the development of related processes leverage the enormous investment in mature Very-Large-Scale Integrated (VLSI) circuit manufacturing. Benefits of this approach include much lower manufacturing cost, greater miniaturization, greater integration, and in many cases higher performance than can be achieved with conventional methods used to build systems requiring sensors and actuators. My research focus on integrated MEMS will eventually lead to the manufacture of low-cost sensor-and-actuator Application-Specific Integrated Circuits (ASICs). Integrated MEMS technology will be pervasive in future embedded systems.
Our research group designs, fabricates, and tests microdevices that are primarily made using a process in high conventional foundry CMOS is followed by simple micromachining steps. This process provides us with high-performance electronics integrated on chip with electrostatically actuated microstructures, capacitive and piezoresistive sensors, and polysilicon thermal heaters. Projects include micromechanisms for magnetic probe-based data storage, accelerometers and gyroscopes for inertial sensing, and ciliary sensors for tactile and acoustic imaging. Of particular interest is how large arrays of these sensors and actuators may improve overall system-level performance. Issues include system design and integration, distributed control and communication, and interfacing to the environment.
MEMS are coupled multi-domain systems and, therefore, are difficult to design without expertise in a diverse set of fields. To address this problem in our lab, MEMS designers and CAD developers work closely together in a synergetic research environment. We are developing a multi-domain hierarchical design methodology to speed up the design cycle. A MEMS schematic is being developed in which mechanical, electromechanical, and electronic elements are graphically interconnected, resulting in rapid simulation and evaluation of designs. We are also modeling topologies for common MEMS applications, such as accelerometry, to codify design constraints for use in automated synthesis tools.