The effect of substrate temperature on Cu(In,Ga)Se2 layers deposited by dual thermal evaporation

Abstract

This paper focuses on the preparation of CuInxGa1-xSe2 (CIGS) by a dual thermal evaporation method only without post-salinization treatment. The effect of substrate temperature on the deposition of stoichiometric layers has been explored. Fabricated CuInxGa1-xSe2 layers were described by energy-dispersive X-ray (EDX), diffraction of X-ray, Raman spectroscopy, atomic force microscopy (AFM), scanning electron microscopy (SEM), Ultraviolet-Visible-Near IR Spectroscopy and the four-point probing technique. CIGS layers of chalcopyrite structures were fabricated successfully with a bandgap of 1.35 eV. The stoichiometry, the grain size and roughness of layers are affected dramatically by the substrate temperature due to re-evaporation of the selenium content during deposition at high temperature. Electrical measurements explain the relationship between electrical conductivity and the value of metal/Se.