A silver indium sulfide (AgInS2) epilayer was grown by the hot wall epitaxy method, which has not been reported previously in the literature. The grown AgInS2 epilayer was found to have the chalcopyrite structure and evaluated to be a high quality crystal. From the photocurrent(pc) measurements in the temperature range from 30 K to 300 K, only two peaks A and B were observed, whereas three peaks A, B, and C were seen in the PC spectrum at 10 K. These peaks are ascribed to band-to-band transitions. The valence band splitting of AgInS2 was investigated by means of the photocurrent measurements. Crystal field splitting, Δcr, and spin orbit splitting, Δso, have been obtained to be 0.150 eV and 0.009 eV at 10 K, respectively. Also, the band gap energy at room temperature has been determined to be 1.868 eV. Further, the temperature dependence of the energy band gap, Eg(T), was determined.

Keywords: AgInS2, hot wall epitaxy, photocurrent, valence band splitting, energy band gap