| Cadmium sulfide (CdS) is an excellent compound semiconductor photoelectric material, and showing potential application prospects in solar cells,optoelectronic devices,photocatalytic materials,nonlinear optical devices and so on.The large scale of CdS films research and application are especially important that study on it may boost the development of optoelectronic technology and its applications.In this dissertation thesis the different spatial dimensions preparation of CdS were introduced. The recent advances and applications were reviewed.Theoretical parts, first of all, it presented the desposition process and growth mechanism of CdS thin films prepared by the chemical bath deposition. Then introduced the laboratory equipment, operational processes, film deposition theory of CdS thin films prepared by vacuum evaporation,and detection means of characterize of CdS thin film.Experimental parts, first of all, presented CdS thin films prepared by the chemical bath deposition. The growth behaviors of CBD-CdS thin films may be influenced by the experimental conditions, such as, the initial reaction solution concentration, deposition time, deposition temperature, ultrasonic vibration and the solution stirring speed. In these conditions factors, the initial reaction solution concentration and deposition temperature were the main conditions factors to determine the thickness of CdS thin films. In addition, post-annealing treatment had greatly affected on the structure, surface morphology and transmittance of CdS thin films. After comparing experimental groups and the characterization of CdS thin films by XRD spectra, SEM graph, Raman spectroscopy, transimission spectroscopy, fluorescence spectroscopy that we have obtained the optimum conditions to deposit CdS thin films in the CBD process. The optimum ranges were:CdCl2 concentration in the range of 0.01 to 0.02mol/L, NH4Cl concentration in the range of 0.02 to 0.04mol/L, SC(NH2)2 concentration in the range of 0.01 to 0.015mol/L, pH value in the range of 10 to 11, temperature in range of 85 to 90℃, deposition time general during from 20 to 30 min, annealing temperature 400℃, and appropriate ultrasonic vibration could benefict reduction film defects reduce the film defects, make thickness uniform and improve transmission rate, ect. In the conditions above, we prepared the large area (20cm×20cm) of CdS thin films, and tested the optical and electrical properties.Secondly, it presented CdS thin films prepared by the vacuum evaporation. Analysis of preparation parameters include evaporation current, deposition time and annealing treatment influencing on the transmittance, structure and surface morphology of the CdS thin films by doing a series of experiment tests and using transmission spectroscopy, XRD spectra, Raman spectroscopy, SEM graph of characterization. When other conditions remained unchanged, the current less than 100A that deposition rate of the CdS thin films increased with the current becomed faster, while the crystallinity of films changed for the better. When other conditions remain unchanged, deposition time in less than 16min and the growth of CdS film thickness was almost linear. Post-annealing treatment would lead to CdS particles with a certain energy that could move within a certain range, as the annealing temperature increased, the particles gained more kinetic energy could be moved to larger and larger particles, and more uniform crystalline better. After annealing at 400℃, the structure, conductivity and optical properties of CdS thin films would be the best. So the optimum ranges were:evaporation current 100A, annealing temputer 400℃, deposition time 15min.Finally, we prepared CdS/Cu2S bilayers by pulling method. Using the chemical bath deposition and vacuum evaporation prepared CdS thin films respectively, then dipping into a solution of CuCl and pulling out to be CdS/Cu2S bilayers. The light resistance and uniformity of CdS/Cu2S bilayers prepared by vacuum evaporation CdS thin films were excellent. In the experiment found that the CdS thin films without annealing and then depositing Cu2S was easy to fall off, annealing above 500℃the bilayer membrane deficit. After tested the photoelectric of CdS/Cu2S bilayers better than CdS monolayer.
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