Electrodeposition of CdTe Semiconductor Layers from Basic Ammoniacal Aqueous Solutions-Thermodynamics, Morphology, and Electrical Properties

摘要

CdTe is a promising material for solar cell applications, since its band gap is suitable for energy conversion from sunlight to electricity. In addition to some non-wet processes, electrodeposition has been investigated for the preparation of polycrystalline CdTe layers, and thin-layered n-CdS/p-CdTe hetero-junction solar cells have already been manufactured industrially. The authors demonstrated that aqueous basic ammoniacal electrolytes, instead of traditional acidic sulfate electrolytes, are suitable for electrodeposition of uniform p-type CdTe layers. In this paper, the behaviors of CdTe electrodeposition from basic electrolytes are reviewed based upon potential-pH diagrams and compared with those from acidic electrolytes. The morphology, microstructure, and electrical properties of electrodeposited CdTe are also discussed.