Process for fabricating a semiconductor gas sensor

摘要

The invention relates to a process for fabricating a semiconductor gas sensor having a metal oxide semiconductor as a core. This sensor can be used in all fields of the national economy as well as in households for measuring reductive gases and vapours. The purpose of the invention is to develop a process for fabricating a gas sensor having high sensitivity and stability which works reproducibly over long periods and has short response and decay times. In particular, it is to be highly sensitive to methane. According to the invention, the gas sensor is fabricated by suitable combinations of stepwise doping with noble metals or noble metal compounds and special baking-out variations in diverse gases, further treatment of tin dioxide by special coating on suitable carrier materials, contacting and heating and final artificial ageing at elevated temperature in a test gas stream. The invention can preferably be applied in the public gas supply, but also in other fields, for example for breathalysers or exhaust-gas measurements.