Cadmium Sulphide Thin Films Grown By Atomic Layer Epitaxy

ABSTRACTPolycrystalline cadmium sulphide (CdS) thin films were grown by Atomic Layer Epitaxy (ALE) using indium tin oxide and tin oxide coated glass substrates. Some of the experiments were made using elemental reactants, and others with inorganic compounds as reactants. Films were characterized using various techniques such as XRD, SEM and optical transmission spectroscopy. Growth rate of CdS films was observed to be 1/4 - 1/3 monolayer per cycle with elemental reactants. A full monolayer/cycle coverage was obtained when using CdCl2 and H2S as reactants. The crystalline structure of the CdS films wis β-cubic (111) when using elemental reactants. The mixed structure was observed when inorganic compounds were used as reactants. Only the hexagonal phase was observed, when substrate surface was pretreated before CdS deposition.