MINIATURIZED INFRARED-SENSOR USING SILICON DIAPHRAGM BASED ON GOLAY CELL

A miniaturized infrared sensor based on the principle of the Golay cel l has been developed. The sensor has a gas chamber and a parallel plan ar capacitor consisting of a thin diaphragm formed by silicon bulk mic romachining. Illumination with infrared light heats the gas in the cha mber and then the deflection of the diaphragm induced by the expansion of the gas is detected as a capacitance change of the capacitor. The chamber of our device is completely sealed and can be filled with vari ous kinds of gas. The sensor containing a certain gas shows a specific response of the intrinsic absorption spectrum of the ambient gas. Sel ective detection of ambient gas has been confirmed using various senso rs containing different gases. (C) 1998 Elsevier Science S.A. All righ ts reserved.