A silicon pressure sensor with stainless diaphragm for high temperature and chemical application

This paper shows how to use silicon pressure sensors for high temperature and silicon corrosive environments. A sensor chip has been developed to be used in high temperature up to 300/spl deg/C, which has SOI (Silicon On Insulator) structure employing Si/Al/sub 2/O/sub 3//Si double hetero-epitaxial technology[1]. The sensor chip is covered with a stainless diaphragm, and never contact with media of pressure. In experiments, a pressure sensor which is designed for a range of 1 MPa has a sensitivity of 18.3 mV/V/MPa. After compensating of the temperature influence, a maximum offset error of 1.3%F.S., and a maximum sensitivity error of 1.1%F.S. from 50/spl deg/C to 200/spl deg/C were obtained.