Structural Analysis of the Formation of CuInSe2

The mechanism of the phase change from Cu2-xSe to CuInSe2 by the absorption of indium selenide is analyzed in terms of the simulation of X-ray diffraction. The crystal structure of Cu2-xSe is proposed on the basis of zincblende structure. The simulated X-ray diffraction patterns indicate that more than half of the anion sites are randomly occupied by selenium atoms with the cation sites being fully occupied with copper atoms in the crystal structure of Cu2-xSe which is regarded as a frame structure of CuInSe2.