Electrical properties of CuInSe2-films prepared by evaporation of Cu2Se and In2Se3 compounds

Abstract

We prepared CuInSe2 films by evaporating In2Se3 and Cu2Se compounds instead of elemental sources, The resulting CuInSe2 film grown at 680 degrees C had a smooth and dense microstructure with the grain size of 2 similar to 3 mu m. But the CuInSe2 films were Cu-rich, with a low resistivity of about 0.1 Omega cm. So we conducted H-2 post annealing to control the electrical resistivity and composition of CuInSe2 films. In a H-2 atmosphere, the resistivity increased to about 100 Omega cm by annealing at 350 degrees C for 1 h. The resistivity decreased again when the annealing temperature was above 350 degrees C, This resistivity change might be related to the contents of Cu, In, Se atoms and the valency states of Cu and In ions in the films. We discussed the reason of resistivity change caused by H-2 post annealing in this paper.