| The Zn doped SnS2 thin films were prepared by vacuum co-evaporation with single source. In order to obtain enhance the properties of the thin films, heat treatments were conducted under different conditions in circumstance of nitrogen. The structure, surface morphology, optical and electrical properties of the film were tested and analyzed by X-ray diffraction, atomic force microscope, manual profiler, X-ray photoelectron spectrum, ultraviolet-visible spectrophotometer, desktop multimeter, cold and hot probe, respectively.The experimental results showed that the film with Sn:S=1:1.5(at%) and heat treatment at 380℃for 15 minutes presented well crystallization. The films showed simple orthorhombic SnS2 polycrystalline, of which the space group was P-3ml(164). The space group of SnS2 thin films prepared with the same ratio of Sn and S at 5wt% or 9wt% Zn doped with heat treatment at 350℃for 30min and 370℃for 20min kept unchanged. Whild the surface topography of Zn-doped films became more compact and rough. The state of Sn and S were Sn4+, S2-, regardless of the doping behaviour. The chemical state of Zn in SnS2 thin films was Zn2+.The surface stoichiometry was Sn:S=1:1.08 in un-doped SnS2 thin films; Sn:S=1.44,Sn:S=1:1.55 respectively in 5wt% and 9wt% Zn doped SnS2 thin films. S in un-doped SnS2 thin film suffered serious losses. Zn doped SnS2 could improve the film stoichiometry obviously and approach the standard stoichiometry.Direct optical band gap of prepared SnS2 films was 2.12eV. After Zn (9wt%) doped, the band gap narrowed to 2.07eV. The resistivity of pure SnS2 thin films was 4.97×102 (Ω·cm). The resistivity of Zn (9wt%) doped films decreased 2 magnitude order, to 2.0 (Ω·cm).The conduction type of all SnS2 thin films were N type.
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