A STUDY OF GAS SENSING PROPERTIES OF OXIDE MULTILAYER THIN FILMS

Abstract- The film structures and gas sensing properties of Fe 0-Ti0-Sn02 oxide n~ultilayer thin films deposited onto the silicon or2t%e czramic substrates have been studied in this paper. The unique double sensing characteristic of the multilayer thin films had high sensitivity and excellent selectivity to NOx and C H OH gas was found. It is considered 5. to be caused by the heterojunctlon an % sleving effects. 1. Intruductiori During the last few years extensive research has been [~~rried out to develop a thin film gas sensor using microelectronic technology. This approach has obvious advantages over conventionally fabricated sensors on ceramic substrates, e.g. small size,low costs due to automatic and batch production, low energy consumption, and the possibility of integration with electronics. However, the preparation of the most important of part of the gas sensor, its gas-sensitive layer, is not able to be fabricated. Truly thin-film gas sensors, deposited by conventional thin film methods, have generally shown poor gas selectivit