Recrystallization of cadmium sulphide films

CdS thin films deposited onto substrates of supremax glass and fused silica were annealed at temperatures of about 700 °C in vacuum or argon atmosphere. Annealing of the samples resulted in a secondary recrystallization due to texture leading to the occurrence of monocrystalline regions with diameters up to a few millimetres. The recrystallization behaviour is similar to that observed by Gilles and Van Cakenberghe [1] and Vecht and Apling [2], however avoids strong doping connected with the technique used by these authors. The presence of oxygen or vapour of one of the components of CdS during annealing prevents the samples from secondary recrystallization, whereas covering of the CdS film with a thin silver film lowers the activation energy of recrystallization and enables therefore recrystallization at lower temperatures.