fabrication and investigation on structural and optical properties of CdS/CdTe bilayer structuer on ITO substrate

Document Type : Full length research Paper

Authors

1 Thin Film Laboratory, Faculty of Physics, Semnan University, Semnan, Iran

2 Faculty of Physics, Semnan University, Semnan, Iran

Abstract

In this investigation, fabrication and investigation on structural and optical properties, the layer growth and quantum efficiency of CdS/ CdTe bi-layer structure on ITO substrate for the production of cadmium telluride- base solar cells are dealt with. The mentioned bi-layer was made by using physical vapor deposition (PVD) method. In order to find the crystal structure of the individual layers or observation of new phase formed at their interface, X-ray diffraction analysis was used. With the help of this analysis, CdTe1-xSx ternary phase was observed at 2Ө=89.95° which has been attributed to the inter diffusion of the two layers. Optical studies show the change in optical transmission compared to the pure cadmium telluride. The surface uniformity and thickness of the specimens and morphology of the grown columns were investigated by FESEM analysis. The FESEM images showed that the layers growth was in uniform columnar form. Quantum efficiency showed that during photovoltaic phenomenon, all photons with a wavelength of 800 nm can produce either an electron. I-V plot study of the prepared bi-layer structure shows a cell efficiency of 1.4 percent and fill factor of 0.65.

Keywords


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