Enhancement in sensitivity of copper sulfide thin film ammonia gas sensor: Effect of swift heavy ion irradiation

The studies are carried out on the effect of swift heavy ion (SHI) irradiation on surface morphology and electrical properties of copper sulfide (Cux S) thin films with three different chemical compositions (x values). The irradiation experiments have been carried out on Cux S films with x=1.4, 1.8, and 2 by 100 MeV gold heavy ions at room temperature. These as-deposited and irradiated thin films have been used to detect ammonia gas at room temperature (300 K). The SHI irradiation treatment on x=1.4 and 1.8 copper sulfide films enhances the sensitivity of the gas sensor. The results are discussed considering high electronic energy deposition by 100 MeV gold heavy ions in a matrix of copper sulfide. © 2009 American Institute of Physics