CONTACT COMBUSTION TYPE GAS SENSOR

PROBLEM TO BE SOLVED: To provide an inexpensive contact combustion type gas sensor in a simple constitution which can obtain larger sensor outputs to combustible gases and therefore can improve a gas detect sensitivity to combustible gases of a low concentration or combustible gases of a low sensitivity. SOLUTION: The contact combustion type gas sensor calibrates a combustible gas by detecting a heat of combustion generated when the combustible gas is burnt. The sensor has a micro heater 4 formed on an Si substrate 2 for promoting burning the combustible gas, a catalyst layer 29 of palladium or the like formed on the micro heater 4 which heats in accordance with a calorific power of the micro heater 4 and acts as a catalyst to burning the combustible gas, and a first and a second thermopiles 5 and 8 set to the vicinity of the catalyst layer 29 and micro heater 4 for detecting the heat of combustion of the combustible gas.