Microtransducer CAD

Microtransducers are miniaturized signal-conversion devices realized using techniques established in the integrated circuit (IC) industry coupled with application-specific thin film deposition and micromachining technologies. Successful design of microtransducers and microsystems critically relies on taking into consideration the interaction of mixed-signal types, e.g., electrical, thermal, mechanical, magnetic, and radiant. Thus computer-aided-design (CAD) tools are becoming increasingly important for analysis and optimization of devices, processes, and systems pertinent to microsystem research and development. In stark contrast to IC device modeling, the field of microtransducer modeling is rather new. Microtransducers and ICs have very different design, and hence, CAD requirements. For example, a microtransducer is designed to interact with the environment, whereas in the IC world devices are shielded from the environment. The design of ICs includes suppression of ``parasitic'' effects while a microtransducer thrives on optimizing such ``parasitic'' effects in a controlled manner for high transduction efficiency. In this paper, the underlying physics, model equations, boundary conditions, and numerical techniques pertinent to microtransducer CAD will be reviewed. Selected examples comprising thermal-based microsensors and micro-electromechanical systems (MEMS) will be presented along with microsystem-level simulation strategies and a discussion of the challenges that lie ahead.