Anneal induced recrystallization of CdTe films electrodeposited on stainless steel foil: The effect of CdCl2

Electrodeposited CdTe films were treated with a saturated solution of CdCl2, and later annealed in air at various temperatures and time durations in order to investigate the influence of post deposition CdCl2 annealing treatments on the structure of the films. The XRD results showed that the CdCl2 treatment has a noticeable influence on the stress, grain growth and the re-crystallization of CdTe. The value of activation energy for 20% re-crystallization in CdTe was estimated as 1.17 ± 0.4 eV and 0.99 ± 0.1 eV respectively for untreated and CdCl2 treated CdTe films. In the early stages of annealing the re-crystallization is dominated by random orientation of the grains followed by a second phase in which once again the crystallites tend to orient in a particular direction. The Lattice constant (a) increases upon annealing and reaches a maximum and on further annealing for a long time it decreases and attains a value less than that of the powder sample.