The Atomization Preparation Of Cds Thin Films And Its Doping Characteristics Of Study

Novel materials, especially optoelectronic and information materials, play an important role in the future development of science and technology. They will promote the development of science and technology, enhance national economy and improve the level of people's daily lives. Cadmium sulfide (CdS) is an important kind of optoelectronic and information materials. The research on CdS will facilitate the development of optoelectronics technology and solar cell, and has a great significance in national economy of our country.In this paper, a comprehensive introduction of CdS, various growth techniques, and the research background had been reviewed. The paper aimed to prepare pure CdS films and doped CdS films on the glass substrates by the ultrasonic spray pyrolysis (USP) method. The solution of cadmium diethyldithiocarbamate (CED) in dimethylsulfoxide was used as the precursor. The X-ray Diffraction (XRD), the Scanning Electron Microscopy (SEM) and the UV-Vis Spectrometer were employed to characterize the crystalline and microstructure of the thin films.The effects of growth parameters, such as doping concentration, substrate temperature, deposition time and annealing, on the quality of CdS thin films have been studied. During the ultrasonic spray pyrolysis process, the substrate temperature played a critical role in the preferential orientation of CdS thin films along c-axis. With the increase in substrate temperature, the preferential orientation along c-axis of CdS thin films was enhanced. However, when the substrate temperature was too high, the preferential orientation was weakened and the crystalline of CdS films deteriorated. Therefore, the appropriate substrate temperature is a key factor for preparing highly preferential oriented CdS films along c-axis. For the Mg doped CdS films, the preferential orientation of c-axis became stronger first and then weaker as the doping concentration increased from 0 to 50 at%. The preferential orientation of c-axis was the strongest when the doping concentration was 10 at%. The doped films were polycrystalline and had hexagonal blende structure characterized by XRD spectra. With the increase of the substrate temperature, the preferential orientation of doped films was enhanced and the FWHM decreased, while the grains became larger estimated according to the Scherrer formula. For the Mg/Mn codoped CdS films, as the proportion of Mn increased, the absorption band of UV transmittance spectra shift towards the longer wavelength. When the proportion of Mn increased further(Mg:Mn=1:5), the absorption band of UV transmittance spectra shift towards the shorter wavelength. The conductive type showed n in un-doped films. When the dope concentration was 10 at%, 30 at% and 50 at%, the conductive type showed p, n and p, respectively. With the increase of doping concentration, the resistivity of doped CdS films increased.