The MOS Device Applied to Hydrogenated Gas Sensor Device

Abstract

The present work reports the MOS (metal/semiconductor/oxide) device application as a gas sensor to H2 and NH3 detection. For this propose we used the C x V curve behavior to study the sensor response by using the change of flat band voltage or capacitance near to flat band state. The sensor showed a nonlinear response as a function of H2 concentration with high sensibility at low gas concentration and low sensibility at high gas concentration. The chemical image response of sensor was obtained by scanning pulse light of small beam on the gate region area. The chemical images pointed out that the sensor response strongly depends on the carrier gas used in the experimental assay.The chemical images patter corresponding to H2 and NH3 didn’t showed significant differences however theirs intensities were clearly different. These results were discussed in the present work.