NOx sensing properties of In2O3 thin films grown by MOCVD

The NOx and O2 sensing properties of highly textured indium oxide In2O3 thin films grown by metal organic chemical vapor deposition (MOCVD) technique have been investigated as a function of the operation temperature and partial pressure. The sensor is very sensitive to NOx and its response is strongly dependent on the gas partial pressure and operating temperature. The responses to NOx and O2 have been found to be maximal at 150 °C. The optimum detection temperature for NOx occurs in the range 150–200 °C considering the response and recovery times. In this range a very low response to O2 is observed indicating that the sensor is very suitable for selective NOx detection.