Oxygen interaction with CdS based gas sensors by varying different preparation parameters

The interaction of oxygen gas atmosphere with CdS films prepared by spray p yrolysis is studied. Spray time and deposition temperature are taken as var iable parameters. The prepared film structure is characterized by XRD to el ucidate the film crystallinity nature and size. Both thickness and crystall ite size of the CdS films decrease as the deposition temperature increases from 340 to 490 degrees C at constant deposition time. The opposite trend w as observed when the films are deposited at different deposition times and constant deposition temperature. The films are exposed to different concent rations of oxygen and the thinner CdS films show higher sensitivity and a s horter response time than the thicker films. The results obtained are promi sing to use the prepared films for detecting oxygen.