Preparation of CIGS solar cell components by improved e-beam ablation technology and control of their final parameters

Abstract

Two step technology for deposition of CuIn/sub 1-x/Ga/sub x/Se/sub 2/ (CIGS) polycrystalline films was developed: deposition with the help of an "e-beam ablation" process at 250/spl deg/C and subsequent selenization at 500/spl deg/C. X-ray diffraction analysis of films showed chalcopyrite structure with stringent <112> orientation. The thin films have optical absorption coefficients in the 10/sup 4/ cm/sup -1/ range and the band gaps are 1.0, 1.4 and 1.65 eV for x=0, 0.25, and 1.0 respectively. The method of admittance spectroscopy for determination of density of concentration of deep states (N(E)) was applied for optimization of the deposition process and the photovoltaic properties. The continuous distribution N(E) has been found.