PbTe/CdTe superlattices on ITO and a solar cell made from CdTe/CdS

Electrochemical Atomic Layer Deposition (ECALD) has been used to deposit CdTe, PbTe and superlattice structure of CdTe/PbTe thin films on ITO coated glass. These are intended to be used as the absorber layer of a solar cell. In our experiments, Cyclic Voltammetry (CV) and current monitoring helped us obtain appropriate deposition potentials. The chemical composition of the films was determined by Energy-Dispersive X-ray Spectroscopy (EDS). We were able to successfully deposit 79.3nm thick stoichiometric film of CdTe. The crystallinity was investigated by x-ray diffraction measurements. Optical absorption measurements were made in order to determine the band gap energy of the deposited films. CdTe/PbTe superlattices were also successfully grown on ITO-coated glass substrates. Recently, we built a CdTe/CdS on ITO solar cell. The stoichiometric composition of CdTe film was deposited using ECALD approach on pre-coated CdS film on ITO substrate. The terminal voltage of our CdTe/CdS solar cell was 0.35V.