Electrodeposition of stoichiometric CdTe thin film for photovoltaic application

Theoretical model based on the Buler-Volmer equation was developed to obtain the potential of perfect stoichiometry (PPS) under a variety of deposited conditions, and results were confirmed experimentally. It also shows that the stoichiometric deviation of CdTe thin film can be controlled accurately. The simulation of electrodeposited process for CdTe was conditioned in the acidic electrolyte containing reducible ions of Cd2+ and HTeO2+. Based on the simulated predictions, well-connected granular CdTe thin films were deposited at PPS. Due to near stoichiometric sample shows slightly p-type, the concentration of HTeO2+ ion was then decrease to reach more intrinsic condition under the PPS applied. Particularly, the p-type, near i-type and n type of CdTe thin films can be electrodeposited se-quentially. The thickness of each layers deposited was achieved by varying the applied potential with different deposited time. (C) 2012 American Institute of Physics. [doi:10.1063/1.3670409]