CdTe films covered with thin layer of Zn were deposited by thermal
evaporation technique. Zn interdiffusion in CdTe was studied by annealing the
prepared films at different temperatures (Tan ) and for different time interval
(tan ). The effect of thermal annleaing temperature (Tan ) and time of annealing
(Tan ) on the optical bandgap energy (Eg), diffusion length (L) and the
corresponding diffuison coefficient (D) is discussed. Results revealed that
during thermal annealing process at 100 °C and after a time of 30 min, a thin
layer of CdZnTe mixed structure have been formed on the top of CdTe films
with variable bandgap between 1.74 and 2.05 eV. The formation of this mixed
structure is attributed to the diffusion process of Zn atom to the top surface of
CdTe film.