Effect of Annealing Temperature on the Structure and Optical Properties of CdS:Cu Thin Films Prepard By Thermal Vacuum Evaporation

Abstract

In this study, we are studying the effect of annealing temperature on
 
 the structure and the optical properties of CdS:Cu thin films which were
 prepared by thermal evaporation technique in vacuum with rate deposition
 (4.1A°/sec) and thickness(=400nm),all these samples have been annealed at
 different annealing temperatures (RT,373,423 and 473 K). The structural
 properties of the films have been studied by using X-ray diffraction. The
 optical measurements indicate that CdS:Cu films have direct optical energy
 gap (E,""), and it decreases from 2.43 eV to 2.37 eV with the increase of
 annealing temperatures (R.T — 473)K. The optical constants refractive
 index (n), extinction coefficient (k),absorption coefficient (a) and dielectric
 constants (€, and €;) were also studied.