Multiparameter integrated sensor development involving alternate materials

Abstract

The sensor community has long been presented with the problem of prioritizing among several competing sensor system variables due to the inability to produce a high confidence, low-cost, reliable, and compact device. Typically a solution for very critical scenarios has been a high-cost scale reduction of larger more laboratory based instrumentation. This often produces data on a single parameter that is beyond reproach, however this can also produce a very delicate, bulky, and costly system often requiring a vacuum system of some sort. An alternative approach involves using micro-opto-electro-mechanical systems (MOEMS) based sensors. This typically results in low-cost and extremely compact devices that often produce dubious or insufficient data. Our approach integrates multiple orthogonal stimuli within a single chip to produce a MOEMS based sensor that has a very high degree of signal confidence. The combination of multiple independent parameters significantly improves detection reliability in a small low-cost package. However, it is often the case that the most efficient MOEMS sensing methods require the use of material properties other than the conventional microlithograph based Si, SiN x , SiO 2 and metals. Thus we have been developing techniques to employ more exotic semiconductors for various sensing applications. The group III-V and II-VI compound semiconductors form a very important and versatile collection of material property variables (thermal, optical, mechanical, electrical) available to the MOEMS designer.