Nanostructured Chalcogenide Thin Films Synthesized by Chemical Methods for Photovoltaic Applications

Abstract

The chalcogenide semiconductors, like CdS, CdSe, CdTe, PbS, PbSe are of great interest for photovoltaic applications, in particular, due to the possibility to be part of multi-layered (tandem) photovoltaic converters. These materials are not expensive and can be produced by economic and ecologically friendly techniques like CBD (Chemical Bath Deposition) and its recent versions (SILAR -Successive Ionic Layer Adsorption and Reaction, and LACBD -Light Assisted Chemical Bath Deposition). It is known that nano--porosity is an essential feature of these techniques. In this paper we study its effects upon the band gap values; the corresponding band gap variations can be used for optimizing the device efficiency. The porosity was modeled by close-packed ball system. In general, we conclude that the quantum confinement effects caused by nano-structuration of semiconductor thin films for photovoltaic converters improve the converter's parameters.