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This article using the vacuum evaporation method on a quartz glass deposited ZnS film and carry out the surface structure and the cross-sectional situation of observation on the film prepared with the atomic force microscope (AFM) and scanning electron microscopy (SEM), simultaneously measuring the absorption of the film transmittance spectrum and photoluminescence spectra. The observation results showed that the Experimental Preparation of ZnS thin film is uniform and dense, small particles, of good quality, and at the same time can be derived based on the measured data of a thin film prepared by a hexagonal (wurtzite) structure of the alpha-ZnS. By to be doped ZnS thin films deposited on a glass substrate, doping elements, Na and Li, to obtain ZnS: Na and ZnS: Li film, the surface of these two doped film and then under the same conditions observations of the structure and the absorption and photoluminescence measurements. The results show that there is an obvious difference in both absorption in the visible range, the light-emitting efficiency varies greatly. The reason for this difference, a wide range of analysis to get a lot of meaningful conclusions, ZnS doping process is a valuable discussion and supplements. Later heat treatment of the thin film is very commonly used in thin-film processing in a way that it has an extremely important role in the film structure and to improve the performance. Preparation of ZnS thin films in an argon gas atmosphere, the annealing treatment, annealing is once every annealing of 100 ° C, the annealing time is 1 h after each annealing observation using SEM, the cross-sectional surface of the film case obtained micro-structural changes of the surface of the film after annealing, while access to the film thickness value. Also tested each after annealing absorption transmission spectrum, photoluminescence spectra, experimental data with theoretical calculations, a thin-film optical bandwidth with annealing temperature changes. The experimental results show that, with the annealing temperature changes, the structure of the film thickness, absorption and photoluminescence intensity in the visible range and so showing obvious regularity changes. From 300 ° C (average thickness for 105 nm) to 700 ° C (an average thickness of 85 nm), with the annealing temperature, the film thickness becomes small, while the average thickness of from 700 ° C to 900 ° C (for 108 nm), with annealing The temperature continues to rise, the film thickness becomes large. Through analysis, we think this is, the reason for the change and defect annealing of the defects of the film where appropriate. In the optical properties, the annealing temperature of 300 ° C to 600 ° C, with increasing temperature, the film reduced optical bandwidth is blue-shifted absorption in the visible region, the visible light region wide and deep level defects related luminescence Tape (DLE) increases; 600 ° C after annealing temperature continues to rise, the thin-film absorption in the visible light region increases, the red-shift in the optical bandwidth, DLE reduced. This article analyzes the main causes of this change, and found that this causes and the causes of the structural changes is essentially the same. On ZnS: Na and ZnS: Li under the same conditions of the annealing process and compare them after annealing the optical properties, the experiment can be seen by their optical properties were tested parameters, annealing for their optical properties significant impact, and annealing can be seen on both the nature of the existence of certain differences. We explore and analyze the physical mechanism of such an impact, and both of them the difference of the optical properties of the theoretical explanation.
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