Influence of grain size on the electrical properties of Sb2Te3 polycrystalline films

Resistance of vacuum deposited Sb2Te3 films of thickness between 100 and 500 nm has been measured in vacuum. It is found that the resistance of the polycrystalline films strongly depends on the grain size and inter-granular voids. The charge carriers are shown to cross this high resistivity inter-granular void by ohmic conduction. The barrier height as well as temperature coefficient of resistance (TCR) are also shown to depend on the grain size and inter-grain voids.