Influence of Deposition Time on the CdS Thin Films Prepared by a Chemical Bath Deposition (CBD)

Abstract

Cadmium sulfide thin layers are frequently used in photovoltaic, especially in the realization of Cu2ZnSnS4 (CZTS) based solar cells as buffer layer. In this work, cadmium sulphide (CdS) thin films have been carried out by using chemical bath deposition (CBD) method. They were deposited onto glass substrates from chemical bath containing cadmium sulfate, thiourea and ammonia at pH = 12. The temperature of the bath was fixed at 60 ºC, and under 150 RPM stirring, the time deposition was varied (10 mn–40 mn). X-ray diffraction revealed the cubic and hexagonal structures formation with secondary phase CdO. AFM images of CdS thin films show that the substrate is covered with granular structures of different size, the root mean square (Rms) value prepared at different time (10 mn, 20 mn, 30 mn and 40 mn) are, 26.05, 25.08, 19.93 and 38.55 nm. High transmission is obtained in the visible and near infra-red.