Study On The Growth And Microstructural Properties Of ZnS_xSe_1-x Thin Films Prepared By Vulcanization And Selenization

In this work,ZnS,ZnSe and ZnS_xSe_1-xfilms were prepared by magnetron sputtering in combination with sulfurization and selenization.The films were characterized by XRD,SEM,EDS,UV-Vis spectrophotometer and Raman spectroscopy and slow positron beam Doppler broadening energy spectrum.The effects of S powder mass on ZnS thin films,deposition temperature on ZnSe thin films,different chemical components on the structure,microstructure defects and optical properties of ZnS_xSe_1-xthin films were studied.The Zn metal films and the sulfur powder of different quality were vulcanized at 500? for 6 hours to prepare ZnS films with different S/Zn molar ratios.The results show that the ZnS films have a hexagonal phase structure.SEM and EDS results show that when the mass of sulfur powder is 1.5 mg,the surface of the film is uniform,the density is the best,and the molar ratio is the best ratio.The results of Doppler broadening energy spectrum and the SEM explain the changes in defect concentration and defect types of the ZnS film.ZnSe thin films were prepared by selenization of Zn metal films and Se powders at different deposition temperatures for 6h.The results show that the ZnSe film has a hexagonal phase structure.The increase of temperature significantly improved the crystallinity of the films,and the light transmittance of the films gradually increased,and the band gap value increased in the range of 2.38eV?2.54eV.The results show that with the increase of temperature,the defect concentration decreases gradually and the defect type tends to be single.The ZnSe films prepared at 700? have the best structure,defect and optical properties.ZnS_xSe_1-xthin films were prepared by sulfurization and selenitization at 700?for 6h with the mixture of sulfur and selenium powder with different molar ratios.The results show that the ZnS_xSe_1-xthin film has a hexagonal phase structure,and the EDS results show that the chemical composition ratio in the thin film is close to the ideal stoichiometric ratio.With the increase of component x,the grain size of the film gradually decreases,while the optical transmittance of the film increases.The defect concentration is obviously affected by component x:when 0<x?0.5,the defect concentration is significantly reduced due to the appearance of cracks on the film surface.When x=0.5,the cracks almost disappear,and the film quality reaches the best.At 0.5<x<1,the surface of film cracks again and the defect concentration increases.The ZnS_xSe_1-xthin films prepared by the selenitization and method successfully achieved the band gap adjustment of 2.53 eV?3.58 eV.