PREPARATION AND PROPERTIES OF CUINS2 THIN-FILMS

A thin film of chalcopyrite CuInS2 has been formed by sulfurization of a layered metallic precursor at 550 degrees C in argon containing H2S. The Cu/In ratio of the film is ranged from 0.8 to 1.85. The resistivity of the film decreases by aging in air and then increases by annealing in vacuum or in air. The former effect can be attributed to gas absorption in the film which gives rise to an increase in the hole mobility, while the latter gives rise to gas desorption. The hole concentration of the films is of the order of 10(20) cm(-3) and is almost independent of aging. Electrical conduction in the thin film is discussed in terms of hole transport crossing over an intergranular potential barrier in the polycrystalline film.