Alternative deposition methods of copper and silver indium ternary sulphides with spinel structure

We compared properties of CuIn5S8 and AgIn5S8 spinel thin films deposited on soda lime glass and sapphire substrates by three methods: a) conventional sulphurisation of a metallic precursor (I), b) alternative evaporation of the binary sulphides with a post-annealing step in sulphur vapour (II), and c) with a post-annealing in decomposition products of bulk spinel in an evacuated ampoule (III). X-ray diffractometry reveals the polycrystalline nature of the films and demonstrates the presence of cubic spinel phases in the films prepared by all the methods. However, the morphology and the electrical transport properties of the spinel films are essentially different. A high Hall mobility of electrons of 10–50 cm2/(V s) was determined in AgIn5S8 films prepared from binary sulphides.