Photoelectrochemical Study of AgInS_2 Thin Films Prepared Using Sulfurization of Evaporated Metal Precursors

摘要

The AgInS_2 polycrystalline films were grow n on glass substrates by using sulfurization of evaporated metal precursors. New procedures for the growth of AgInS_2 films are presented.. The influences of [Ag]/[In] molar ratio in the precursor films on structural, optical, electrical performances of films have been investigated. The X-ray diffraction patterns of the samples demonstrate the presence of polycrystalline structures of AgInS_2 phase in these films. The band gaps and carrier densities of these samples determined from transmittance spectra and electrochemical analysis are in the range of 1.92-4.94 eV, and 3.2x10~(20)～4.0x10~(20) cm~3, respectively. The flat band potentials of these samples are located between -0.83 and -1.10 V versus normal hydrogen electrode with the Mott-Schottky measurements. The maximum photocurrent density of samples prepared in this study with external potential kept at +1.0 V (vs. Ag/AgCl electrode) was found to be 4.4 mA/cm~2 under the illumination with white light intensity kept at 100 mW/cm~2.