Effects of synthesis temperature on CuIn(S,Se)_2 thin films prepared by one-step evaporation of Cu-In precursors

摘要

CuIn(S,Se)_2 thin films were grown on soda-lime glass substrates by one-step evaporation Cu-In precursors processes. Effects of synthesis temperature on the structural and optical properties of CuIn(S,Se)_2 absorption layers were studied. The changes of surface morphology among different samples were observed by field-emission scanning electron microscopy. From X-ray diffraction images and Raman spectra, the CuIn(S,Se)_2 films had good crystallinity quality when the synthesis temperature was 550 ℃. The FWHM of (112) peaks decreased from 0.537° to 0.180°, and secondary phase Cu_x(S,Se) disappeared when the synthesis temperature increased from 300 to 550 ℃. The Raman spectra of the films also showed the CuIn(S,Se)_2 A_1 mode peaks existed chalcopyrite, and the blue shift of the CuIn(S,Se)_2 A_1 mode peaks from 289 to 284 cm~(-1). The optical properties of the films were showed by transmission spectra, and the energy band gap of the CuIn(S,Se)_2 thin films fabricated at 550 ℃ is 1.34 eV.