An integrated gas sensor fabricated on a silicon substrate

摘要

We have developed an integrated thin-film gas sensor using semiconducting thin-films on an SiO_2 diaphragm, which is formed on an Si substrate. A micro heater is fabricated on the same diaphragm. The fabrication procedure is based on thin-film and micromachining technologies and IC fabrication process. The two sensing films are composed of multi-layered metal oxides; an SnO_2-based film on an Fe_2O_3-based film and a WO_3-based film on an Fe_2O_3-based film.