Optical Characterization of CuInSe₂ Thin Films Grown by Metal Organic Chemical Vapor Deposition

Abstract

We studied the photoluminescence (PL) in CuInSe2 thin films grown by metal organic chemical vapor deposition (MOCVD) using a Cu precursor and two gases. By X-ray diffraction (XRD) and PL analysis, we found that the best quality of CuInSe2 thin films can be obtained when the deposition time of the trimethylindium (TMI) gas is 30 min. The improvement of the quality of CuInSe2 thin films after rapid thermal annealing (RTA) is evident from the full width at half maximum (FWHM) of PL. The FWHM of the PL peak is minimum when the RTA temperature is 500 °C. It is found the binding energy of the impurity level in CuInSe2 thin films increases after RTA, revealing that the thermal stability of CuInSe2 thin films is improved after RTA.