For improving the energy conversion efficiency of solar cells, it is essential to reduce the surface recombination velocity of CuInSe2 absorber layer. The use of quaternary alloys with an increasing band gap gradient was also demonstrated to be effectively increased the open-circuit voltage of the cells. The experiments using different concentration ammonium sulfur solutions to proceed surface passivation and sulfurization of CuInSe2 and CuInSe2¡GSb films have been conducted to evaluate their influences on the band gap and other related properties. The band gaps of Cu-rich and In-rich CuInSe2 films did not change after ammonium sulfur treatment. For CuInSe2¡GSb films after immersing (NH4)2Sx solution, the PL spectra gave an evidence of the formation of the quaternary CuInSxSe2-x alloys. The metal contacts to CuInSe2 films with the structures of Mo/P-type CuInSe2/Al and Mo/N-type CuInSe2/Au had been fabricated. Their I-V characteristics indicate that the Schottky Contacts had been successfully formed.