The Synthesis And Photoelectric Characteristics Of The Oxide Coated Porous Semiconductor Structures

In this thesis, the nanocomposite materials were prepared in the porous semiconductor material, and its photoelectric characteristics were investigated. The main works of this thesis as follows:1. By the Ag-assisted chemical etching technology, highly oriented Si nanowire arrays?Si NWs? on the Si wafer were synthesized. The TiO₂ was deposited on the surface of Si NWs by atomic layer deposition?ALD? technology. After deposition, annealing process was carried out to improve the crystalline quality of the TiO₂ shell. The results indicate that the annealing treatment did not affect the crystal quality of Si material in the nanocomposite materials, leaving the material TiO₂ from amorphous into polycrystalline. The sample with annealed at 500 ?,the anatase TiO₂ had the best crystalline quality. The degradation of methyl orange was up to 88% after 6h of irradiation.2. Indium phosphide?InP? nanoporous material have been successfully fabricated by electrochemical etching technology. The InP nanoporous were passivated by?NH4?2S solution, and the photoluminescence properties were improved. Using ALD and the hydrothermal method at InP surface of the porous material prepared ZnO material having branched structure formed InP/ZnO nanocomposites. The response performance of the nanocomposite structures was carried out. The results show that the nanocomposite structure has a response in the wavelength range of 350-1000 nm.