| 摘要 |
PURPOSE:To prevent deterioration of a substrate due to a high temp. reducing atmosphere, by forming a dense coating layer on the surface of the insulating substrate prepd. by adding a contracting agent to a gas-sensitive metallic oxide semiconductor. CONSTITUTION:The region 2 of the substrate of the gas detection element is made of an insulating material prepd. by adding 0.1-2wt% CuO, MnO2, ZnO, or the like contracting agent to a gas-sensitive metallic oxide semiconductor of SnO2, TiO2, In2O3 or the like. The gas sensing region 3 is made of said semiconductor alone or contg. a small amt. of noble metal co-catalyst. Electrode regions 3, 4, are made of a semiconductor, e.g., SnO2 contg. 0.5wt% CuO and about 25wt% Pt as a contracting agent. A dense glass coating layer 6 made of glass, cement, or the like is formed on the region 2 except the region 3 to protect the element, thus preventing deterioration of the region 2 due to a high temp. reducing atmosphere. |
