A LOW-POWER CMOS COMPATIBLE INTEGRATED GAS SENSOR USING MASKLESS TIN OXIDE SPUTTERING

This paper describes a CMOS compatible integrated gas sensor. The devi ce was designed so that the front-end fabrication is fully compatible with the standard CMOS process. The non-CMOS compatible fabrication st eps were carried out as post-processing steps. This included the silic on anisotropic etch to create the thermally isolated micro-hotplate (M HP) and the deposition of gas-sensitive thin films using maskless r.f. SnO2 sputtering. The sensors exhibited high sensitivities to gases, s uch as ethanol and hydrogen. (C) 1998 Elsevier Science S.A. All rights reserved.