Research On Fabrication Technology For Tandem Amorphous Silicon Solar Cells

With the increasing demand of renewable and environmentally acceptable terrestrial energy resources,solar energy has been one of the most promising energy resources. Solar radiation is inexhaustible,no-pollution,low-cost,which become a new way to ease the energy shortage. Compared with crystal silicon solar cells the thin film a-Si:H solar cells have advantages as following:The fabrication technology of a-Si:H solar cells is simple.The low deposition temperature,and using the low cost of material make the low cost of a-Si:H solar cells,and easy to integration.But single junction based amorphous solar cell conversion efficiency is low,and have S-W effect.Tandem a-Si:H solar cell enhance the solar photovoltaic conversion efficiency and stability by the band gap adjustments. In this thesis we have investigated a-Si:H tandem thin film solar cell both theoretically and experimentally.Focusing on the above research direction,this paper detailedly investigated the technology which taking H₂,SiH₄,B₂H₆,PH₃andCH₄ as reaction gases to prepare different layers by PECVD.We have investigated the preparation of amorphous silicon thin film and the influence of deposition parameters on its electrical and optical properties.By optimizing the preparation condition of a-Si:H,and solar cell design we succeeded to prepare a a-SiC/a-Si single junction solar cell with conversion efficiency 4.09%(Voc=0.82V,Jsc=7.25mA/cm²) at a lower substrate temperature of less than 200℃.Than we succeeded to prepare a a-SiC/a-Si double junction solar cell with conversion efficiency 4.64%(Voc=1.18V,Jsc=6.28mA/cm²).In order to improve output power,we designed the make to make the solar cell integration.