BETRIEBSVERFAHREN FUER EINEN SENSOR FUER GASANALYSE.

摘要

The presence of one or more components in a gas mixt. is detected by the consequent emission of an electric signal from a sensor which reaches its terminal value after a specific interval. Progressive changes in the signal as it strengthens or dies away after subjection to the mixt. are recorded and evaluated. A suitable sensor has an MOS detector (10) on a semiconductor substrate (21), with a protective SiO2 coating (3) below a gate valve layer (4). The catalytically active layer of Pd etc. (5) is coupled to a terminal (15), and may be covered by a zeolite layer (31) specific to detection of a particular gas. Adjacent is a resistance heater system (6). Detector temp. pref. differs from ambient value, and be modulated e.g. at specific frequency, while readings are taken.