Raman Spectra of CuInSe ₂ Thin Films Prepared by Chemical Spray Pyrolysis

Abstract

Raman spectra have been investigated for CuInSe 2 polycrystalline thin films prepared by chemical spray pyrolysis. The A 1 mode Raman peak at 174 cm -1 , the dominant peak in CuInSe 2 with a chalcopyrite structure, and a peak at 182 cm -1 have been observed. The A 1 mode peak is dominant for Cu-rich films and stoichiometric films deposited at high substrate temperature. On the other hand, the 182 cm -1 peak is dominant for In-rich films and stoichiometric films deposited at low substrate temperature. By comparing the Raman results with the X-ray diffraction measurements, the peak at 182 cm -1 is found to be characteristic of CuInSe 2 with a sphalerite structure.