Abstract:(NH4 ) 2 S was used to passivate P+ 2type InP, and thermal annealing at different temperature was followed. In order to appraise the effects of the surface electronic properties, Photoluminescence was used to achieve the photo-luminescence ( PL) intensity of sulfided samp les thermally annealed at different temperature. In order to understand the sulfur passivation mechanism, X-ray photoelectron spectroscopy (XPS) was used to investigate chemical binding states of the samp les.