Optical Properties Of Silicon Nanowire Materials And SiNWs Solar Cell Simulation

Silicon nanowires material(SiNWs) is a novel kind of one-dimensional material. It has many unique optical and electrical properties which are different from bulk silicon material due to its nanometer magnitude structure. In recent years, silicon nanowires material has aroused great interest in the field of basic research and applied research. The Single-electron effects and the Coulomb blockade effects has been observed in the silicon nanowires material, which is resulted from the small size and the surface morphology of the nanowires. Because of its outstanding electrical and optical properties, silicon nanowires material will play an important role in future nano-electronics and nano-optics connections and functional devices development.The unique physical properties the preparation methods of silicon nanowires material are briefly introduced in this thesis. Aligned identical silicon nanowires array were prepared on single crystalline p-Si<100> wafers by the metal catalyzed chemical etching method under normal conditions(room temperature,1.01xl05Pa). The morphologies of prepared samples, reflection spectrum, transmission spectrum and absorption property are analyzed. The reflection spectrum show that the obtained SiNWs arrays could drastically suppress the optical reflection over a wide spectral bandwidth ranging of200~1lOOnm, the reflectance is about3.5%. The length of the silicon nanowire arrays used as the antireflective layer of solar cell should be less than1.O6.μm and the etching time should be controlled less than2min, in order to ensure high efficiency of silicon nanowires solar cells.Flat silicon nanowires solar cells with different thickness of nanowires layer are simulated by PC-ID simulation software. Some important solar cell parameters, such as I-V characteristic, external quantum efficiency and photoelectric conversion efficiency are calculated and discussed. When the nanowires have a thickness ofO.6μm, a short-circuit current of37.58mA/cm+2and a photoelectric conversion efficiency up to14.54%of SiNWs solar cells have been got, which provides a reference for the actual preparation of the silicon nanowires solar cells.