CMOS AS SENSOR TECHNOLOGY

Sensor design and fabrication using industrial IC technologies has the advantages of batch fabrication and on-chip interface circuitry. Sens ors made by CMOS or bipolar IC technology have been demonstrated for m agnetic, temperature and radiation measurands. Certain thermal, mechan ical and chemical sensors can be realized by combining IC technologies with additional, compatible processing. We distinguish the methods of multiple project wafers, single project wafers, post-processing IC ch ips or wafers, and IC fabrication merged with sensor processing perfor med before, after, and in-between the regular IC processing steps. Thi s paper is focused on sensor prototypes realized by industrial CMOS IC technology with post-processing micromachining. Examples include ther mally excited acoustic resonators, thermoelectric gas flow, infrared, and power sensors, and a thermal conductivity sensor.