2.51 eV photoluminescence from Zn-doped CuAlSe2 epilayers grown by low-pressure metalorganic chemical vapor deposition

A photoluminescence (PL) peak at 2.51 eV was observed at 77 K in Zn-doped CuAlSe2 chalcopyrite semiconductor epilayers grown by a low-pressure metalorganic chemical vapor deposition. The emission can be seen as blue-green. The PL peak at 2.51 eV was absent in Al-rich epilayers. Photoreflectance measurements were performed on both undoped and Zn-doped CuAlSe2 epilayers. Zn doping up to the level of 0.02 at. % did not affect the valence band profile.