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Cadmium sulfide (CdS) is excellent semiconductor optoelectronic materials, and has broad prospects for application in solar cells and optoelectronic devices, photocatalytic materials and nonlinear optics. Especially on large-scale preparation of CdS thin films and applications, the completion of the research work, and will promote the development of photovoltaic technology and its applications. This article has a more detailed description of research on materials of different spatial dimensions CdS preparation method and application prospects. The theoretical part: First, the growth mechanism of the chemical bath deposition Preparation of CdS thin films. Second, the the vacuum evaporation prepared CdS thin film laboratory equipment, operational processes, film-forming principle and Characterization of CdS thin films means of detection. Experimental parts: First, introduce a chemical bath deposition prepared CdS thin films. CBD deposition of CdS thin films experiments, it is found that the growth of CdS thin films by a variety of factors such as: the initial concentration of the reaction solution, deposition time, deposition temperature, ultrasonic vibration and the solution is stirred for speed, etc.. These factors to determine the thickness of the CdS film is mainly the initial concentration and the deposition temperature of the reaction solution. Moreover, the late annealing treatment on the structure, morphology and transmittance of CdS films also have a great impact. After packet comparative experiments and XRD spectrum, SEM image, Raman spectroscopy, transmission spectroscopy, fluorescence spectroscopy characterization of CdS thin films derived from the quality preparation of CdS thin films best: CdCl2 at a concentration range of select 0.01 ~ 0.02 mol / L of NH4Cl the concentration range is selected as 0.02 to 0.04 mol / L, SC (NH2) 2 in the concentration range is selected as 0.01-0.015mol / L, a pH value range is selected as 10-11, the reaction temperature is controlled at 85-90 ° C, The deposition time is 20-30min, and the annealing temperature was 400 ° C. And appropriate ultrasonicated film defects can be reduced, uniform thickness, and the transmittance was improved. CdS films prepared under the above conditions, the large area (20cm × 20cm), and tested the light conductive characteristics. Secondly, the vacuum evaporation Preparation of CdS thin films. By a series of experiments and research by means of transmission spectra, XRD spectrum, SEM image, characterized evaporation current, deposition time and annealing treatment preparation parameters on the transmittance of CdS films, structure and surface morphology. When other conditions remain unchanged, in the case of evaporation current of less than 100A, CdS film deposition rate with increasing evaporation current becomes faster, while crystallization of the film becomes good; when other conditions remain unchanged, deposition time 16min within the CdS film thickness growth almost linear; the latter part of the annealing process, make the CdS particles having a certain energy, can move within a certain range, with the increase in the temperature of annealing treatment, the particles to obtain more kinetic energy of the can greater range of movement, to form a larger particle groups, and more uniform, better crystalline CdS thin film structure after the annealing at 400 ° C, the conductive and optical properties. The best preparation conditions for the final CdS films: evaporation current: 100A, annealing temperature: 400 ℃, deposition time: 15 min. Finally, the legal system with pulling to prepare CdS/Cu2S bilayer. Were prepared using chemical bath deposition method and a vacuum evaporation method out of the CdS film was immersed into a solution of CuCl, and then pulling Preparation out CdS/Cu2S bilayer membrane. Prepared by the vacuum evaporation method, the CdS film so superior light resistance and uniformity of the film of the CdS/Cu2S bilayers the CBD method CdS films prepared by CdS/Cu2S double membrane. Experiment found easy to fall off, Cu2S deposition on the CdS films without annealing, annealing above 500 ℃, the bilayer membrane defects. Via the bilayer membrane photoconductive test CdS/Cu2S better than CdS monolayer.
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