On the capability of revealing the pseudosymmetry of the chalcopyrite-type crystal structure

The tetragonal crystal-structure type of chalcopyrites (chemical formula A^IB^IIIC^VI₂) is a superstructure of sphalerite type. The c/a ratio differs generally from the ideal value 2, i.e., the crystal structure is pseudocubically distorted. For CuInSe₂ and CuGaSe₂ thin films, simulations demonstrate that it is theoretically possible to reveal the tetragonality in electron backscatter-diffraction (EBSD) patterns for CuGaSe₂, whereas it may not be possible for CuInSe ₂. EBSD experiments on CuGaSe₂ thin films using the "Advanced Fit" band-detection method show that it is possible to extract accurate misorientation-angle distributions from the CuGaSe₂ thin film. Pole figures revealing the texture of the CuGaSe₂ thin film are shown, which agree well with X-ray texture measurements from the same layer.