Technology Considerations For Integrated Multifunctional Silicon Sensors

Abstract

Multifunctional silicon integrated sensors have been fabricated for simultaneous measurement of several physical and chemical variables. These sensors are based on the compatible introduction of thin films of piezoelectric and pyroelectric zinc oxide combined with conventional MOS processing technology in the fabrication of 1) a 64-element infrared sensing array, 2) a mass air-flow sensor, 3) a tactile sensor array for precision robotics applications, 4) carbon monoxide sensor, 5) surface-acoustic wave chemical vapor sensor, 6) microbeam accelerometer, and 7) infrared charge-coupled device imager. This paper specifically addresses technology issues involved in incorporating sensors with high-performance silicon integrated circuits. Focus is directed toward 1) zinc oxide based sensors, 2) silicon micromachining pf sensor membranes, and 3) compatible processing issues necessary for a generic integrated sensor technology. Performance examples for a 64-element room-temperature pyroelectric imager are presented.