Optimization of Optical Properties of Annealed Cadmium Selenide (Cdse) Thin Films Grown by Chemical Bath Deposition Technique

Abstract

Two groups of cadmium selenide thin films deposited at 25⁰C and 74⁰C respectively on glass substrates by chemical bath deposition method were studied. A moderately stable sodium selenosulphite (Na₂SeSo₃) was used as a source of Se^2- ions. To prevent spontaneous precipitation and ensure ion-by-ion deposition on the substrate, TEA was used as a complexing agent. The optical characterization was centered on transmittance, reflectance for the annealed and various annealing temperature of thin film. The structural nature was obtained from X-ray diffraction (XRD) analysis. The optical properties were obtained from absorption and transmittance data within the range of 200-to-1000nm. Some of the films were found to have a good transmittance and low reflectance hence suitable for window coatings for cold climates and antireflection coatings.

Key Words: - Characterization, Deposition and annealing temperature and time, optical, Chemical Bath Technique, Cadmium Selenide thin Films, annealing, transmittance, reflectance, band gap.