Research On The Growth Quality And Microstructure Of ZnS And ZnS:Cu Thin Film Prepared By Sulfurization

As an important direct type administered broadband gap compound semiconductor material,ZnS has the forbidden band width in the range of 3.5 ? 3.7 e V,greater than the forbidden band width of CdS(2.4 eV).In visible and infrared regions,ZnS thin films have low optical absorption and high refractive index.And ZnS thin films play a great role in optoelectronic device.There are many kinds of way in preparaing ZnS thin films both at home and abroad,mainly gas phase method and liquid phase method.The gas phase method includes the magnetron sputtering method,thermal evaporation method,pulsed laser deposition method and ion beam assisted deposition method,etc.ZnS thin films prepared by magnetron sputtering method have the properties of high density and homogeneity,etc.In the process of annealing treatment,atoms inside film proliferation gain enough energy to produce migration which leads to some point defect restoration,thus reduce defects within the thin film.Then thin film stress is relaxed.In this paper,ZnS thin film have been prepared by sulfurizing zinc thin film which deposited on substrate by magnetron sputtering.ZnS films produced at 445 ? have the minimum structural defect concentration and the highest density.XRD results show that films are blende structure with the preference of(111)orientation above 400 ?.In the range of 410 ? to 440 ?,the preferred orientation of ZnS thin films transforms(200)crystalline planes into(111)crystalline planes.And the phenomenon that the composite target material form and pretreatment of Zn or Zn:Cu films have a significant effect on ZnS or ZnS:Cu films density,homogeneity and grain size has been found.