DETERMINATION OF THE CRYSTALLOGRAPHIC ORIENTATION OF CUINSE2 THIN-FILMS BY RAMAN AND INFRARED-SPECTROSCOPY

Polarized Raman spectra were measured at room temperature from the (00 1)- and (112)-oriented CuInSe2 heteroepitaxial layers grown on (001)- and (Ill)-oriented Si substrates. The analysis of the results proved t he expected orientation and good crystalline quality of the (001) laye rs. No special crystallographic direction was identified unambiguously on the (112) plane. Similar behavior was confirmed by infrared transm ission spectroscopy. This can be explained by the existence of rotatio nal twins, which have been observed by x-ray diffraction. (C) 1997 Ame rican Institute of Physics.