abstract |
A sensor comprising a metal heat generating member formed with a heat-resistant insulating coating of Al₂O₃ or the like over its surface, and an atmosphere-sensitive layer of SnO₂ or the like supported on the coating. The insulating coating is formed, for example, by alumina sol coating and thermal decomposition, or plasma CVD of an aluminum compound. The sensitive layer is formed, for example, by the thermal decomposition of an organic compound of tin, vacuum evaporation or sputtering of tin, or printing of SnO₂ on the heat generating member when the member is in the form of a flat plate. At least one electrode is connected to the sensitive layer for deriving an output from the layer in response to a combustible gas, humidity or the like. |