Fabrication And Properties Of Sulfide Thin Films, And The Patterned Thin Films

Sulfide semiconductor nanomaterials have novel optical physical properties,they have a wide range of light absorption, so, they can greatly improve the lightabsorption efficiency, and they can prepare super ionic conductors. Inphotoluminescence, sensors, photoelectric conversion, and other materials have anirreplaceable role, and they have good prospects in the field of solar cells. Since theimportant applications in microelectronics, chips, micro electro-mechanical systermsetc, now that micro and nano-scale surface micro-machining or design technology ona solid surface has been developing at a tremendous pace.Based on the ultraviolet lithography process and the modification of substratesby self-assembled monolayers (SAMs), the CdS, and In₂S₃ thin films and thepatterned thin films were successfully fabricated using the chemical bath depositionmethod in this work. The optical, photoelectrochemical, and electrical properties ofthe thin films have been performed. The main results of this thesis are drawn asbelow:1. The CdS thin films were prepared using chemical bath deposition method,and the best deposition condition was discussed.The surface morphologies of theCdS thin films were examined using a field emission scanning electron microscope(FESEM). The structure and the phase composition were analyzed by X-raydiffraction (XRD) and X-ray photoelectron spectroscope (XPS). The opticalabsorption and photoelectrochemical response properties of the thin films weremeasured using an UV-Vis spectrophotometer and an electrochemical workstation.The results show that CdS thin films with strong absorption in the short wavelengthregions, which meet the requirements of solar cells window material and transitionlayer. UV-vis spectrum shows that the photoelectric spectrum of CdS thin films showa strong photoelectric response and hold the typical features of n-typesemiconductor.2. The patterned CdS thin films were fabricated by a chemical bath depositiontechnique combined with the ultraviolet lithography method, with a better selectivity,the clear pattern boundaries, and the complete uniform. The characterization andphotoelectrochemical properties of the patterned CdS microarrays, along with theeffects of the pattern features on the optical and photoelectrochemical properties ofpatterned thin films were investigated. The results show that this method can be usedto effectively regulate the surface feature size as well as photoelectrochemicalproperties of CdS thin films.3. The In₂S₃ thin films were prepared using chemical bath deposition method.The surface morphologies of the In₂S₃ thin films were examined using a fieldemission scanning electron microscope (FESEM). The structure and the phasecomposition were analyzed by X-ray diffraction (XRD) and X-ray photoelectronspectroscope (XPS). The optical absorption and photoelectrochemical responseproperties of the thin films were measured using an UV-Vis spectrophotometer andan electrochemical workstation. The results show that the optical absorption andphotoelectrochemical response properties of the thin films can be controlled byadjusting the deposition time.4. The patterned In₂S₃ thin films were fabricated by a chemical bath depositiontechnique combined with the ultraviolet lithography method. The effects of SAMswith different functional groups for patterned In₂S₃ thin films growth were discussed.The behaviors of controlling the particles growth on the substrates were investigated.The positive and negative patterned In₂S₃ thin films were successfully fabricated.The results show that the patterned In₂S₃ thin films were fabricated by a chemicalbath deposition technique combined with the ultraviolet lithography method, with abetter selectivity, the clear pattern boundaries, and the complete uniform.