| 摘要 |
PURPOSE:To obtain a inflamable gas detecting element that detects the concentration of inflamable gas in a high sensitivity by reading the variation of temperature caused by adsorption and desorption of the gas, by providing a layer of metallic oxide semiconductor showing a high sensitivity to the inflamable gas on the surface of a thin platinum film resistor. CONSTITUTION:An alumina tube or transparent quartz tube 1 is washed, and then a uniform thin film of platinum is formed by a sputtering device having a rotary jig. This thin film is then stabilized with a heat aging to form a thin platimum film resistor 2. The resistor 2 undergoes a trimming by a diamond cutter or laser cutter to obtain a desired value of resistance, and the platinum lead wires 4 for signal extraction are attached across the resistor by baking the platinum wires with the platinum paste. Thereafter, a thin film or thick film 3 of semiconductor oxide is formed uniformly on the surface of the resistor 2 by the sputtering method or painting method. The resistor is then stabilized with heat aging, and the heater 5 is incorporated. Thus a desired detecting element is obtained. |
