COMBUSTIBLE GAS SENSOR

The present invention provides a combustible gas sensor that can realize a considerable improvement in the measurement sensitivity and the measurement precision by increasing the contact area between the measurement object gas and the oxidation catalyst particles, increasing the amount of heat generation of oxidation reaction in accordance therewith, and improving the transference of the oxidation reaction heat, while reducing the scale of the whole. In this invention, a temperature measurement element such as a thermopile obtained by joining different kinds of metals is formed on a top surface of a Si substrate; a porous catalyst layer made by allowing a porous material layer to carry oxidation catalyst particles such as Pt or a chain-form catalyst layer made by linking and bonding numerous oxidation catalyst particles in a chain form is provided on a heat-sensitive part of this temperature measurement element; and this porous catalyst layer or the chain-form catalyst layer is integrally bonded with the heat-sensitive part of this temperature measurement element.