A COMPARATIVE STUDY OF THE PROPERTIES OF SPRAY-DEPOSITED Sb_2Se_3 THIN FILMS PREPARED FROM AQUEOUS AND NONAQUEOUS MEDIA

摘要

Semiconducting antimony triselenide thin films were obtained by spray- depositing aqueous and nonaqueous media, at optimized substrate temperature and solution concentration, onto optically fiat glass substrates. Film thickness was of the order of 0.5 um. X-ray diffraction studies revealed that the as-deposited films prepared from the aqueous medium were polycrystalline, while those prepared from the nonaqueous medium were amorphous. The optical gap of the Sb_2Se_3 thin films prepared from the aqueous medium was l.88 eV, due to direct interband transition. In contrast, the optical gap for the films prepared from the nonaqueous medium was l.73 eV. Room-temperature electrical resistivity for the films prepared from both media was found to be of approximately the same order, l0~7 Ω -cm. Thermoelectric power (TEP) measurement studies revealed that the films prepared from both media showed p-type conductivity, with Seebeck coefficients of 46.2 and l8.3 uV/deg.C for the polycrystalline and amorphous Sb_2Se_3 thin films, respectively.