Research On Silicon Nanowires And Selective Diffusion For Crystalline Silicon

As a new one-dimensional nanomaterial,SiNWs has attracted much attention owing to its own unique optical and electrical properties. The researchers focus their attention on how to control the morphology of the product,exploit the mechanism of growth process and investigate or improve the properties of the nanostructures. As we all know, silicon is a wonderful material for solar cells and there has been intense research on various aspects. Investigation into Characteristics of electronic transmission, optical absorption properties and the excellent photosensitivity in SiNWs was becoming the highlight of silicon nanowire solar cells.Firstly, Synthesis, Characterization and Application of SiNWs were studyed in this thesis, one dimensional SiNWs has been synthesized by metal-particle-induced chemical etching technique. The as-prepared samples were characterized by morphology and growth structure of SiNWs; Seondly, the study on seleetive diffusion for crystalline silicon solar cell was introduced, including the explain away strueture of seleetive emitter solar cell and the technological design of seleetive diffusion.1. Large-area aligned high quality silicon nanowire arrays were formed in 4.6mol/L HF and 0.02 mol/L AgNO3 etching solutions using a novel metal-particle-induced chemical etch-ing technique at etching temperature of 50℃, etching time of 30min. The theoretical analysis and experimental studying indicated that SiNWs were prepared from the bulk silicon with the development of the up-bottom fabrication. The length of single crystal SiNWs was related with the Experimental Conditions. The experimental results showed that SiNWs had different morphologies and microstructures as a result of the experimental conditions. SiNWs synthesized at above condition had good growing orientation, uniform structure and less defects.2. As far as the new technology of selective diffusion, the method is used by SiO2 barrier diffusion and Lithography mask technology with phosphorous paste as diffusion source. The result is showed that the value of sheet resistence is 43.2Ωin heavily doping area and 89.1Ωin lightly doping area. The difference is 45.9Ω.Therefore, the selective diffusion is brought about successfully.3. The diffusion is studyed in nomal diffusion furnace and The values of the sheet resis-tence decrease as the reaction temperatures increase.The result is showed that the excellent diffusion characteristics with phosphorous paste is changed with technology.So, The phosphorous paste has excellent diffusion performance and is suited for fabricating selective emitter.