Advanced silicon microstructures, sensors, and systems

This paper presents the progress in silicon-based biomedical microstructures, material characterization techniques, and mechanical microsystems by the authors' research team. Microneedle and microelectrode arrays with fluidic through-wafer vias and electrical contacts were developed. The structures are designed for dermatological and biological applications such as allergy testing, surface electromyography, and spatially resolved impedance spectroscopy. The characterization of thin films has relied on the bulge test. By the formulation of more powerful models, the application range of the bulge test was extended to elastically supported thin-film multilayers. This enables the mechanical properties of thin films to be determined reliably. Finally, progress in the operation and application of novel stress sensors based on CMOS diffusions and field effect transistors and exploiting the pseudo-Hall effect is reported. Their integration into powerful single-chip microsystems is described. Applications include stress mapping, force and torque measurements, and tactile surface probing of microcomponents. (c) 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.