Computer Simulation Of N-Type HIT And The Passivate Role Of The Buffer Layer

Sanyo developed a solar cell which is a hybrid composed of a N-type single crystal silicon wafer surrounded by layers of thin amorphous silicon HIT(hetero junction with intrinsic thin-layer). The HIT both have the advantages of the crystalline silicon solar cells and thin film solar cells. The efficiency of the solar is better and it can be made easily. Now, the research of the HIT with N-type subtrate in china is far behind Sanyo. We should do more research on it and that's the goal of this paper. The main results are as follows:1. The performance of a-Si: H /c-Si hetero-junction solar cells is simulated by AFORS-HET software. The short current (ISC) decreased and the short wave response became worse with increasing the thickness of emitter layer. The open circuit voltages and fill factors decreased rapidly with the density of interface defect state(sDit), while short current is not sensitive to Dit. By inserting an intrinsic layer with the thickness less than 30 nm on the interface of a-Si: H /c-Si as the buffer layer, the performance of the solar cells increased significantly. The deserved efficiency with bifacial intrinsic layer for a-Si/ i-a-Si:H/ c-Si/ i-a-Si:H/n+a-Si sollar sell is achieved to 28.45%.2. We use plasma enhanced CVD equipment in preparation of the silicon-based thin film on the silicon substrate. We compared the passive role of silicon-based thin film on silicon substrate and the effect of factor of the equipment by test the minor-carrier lifet ime of the sample. At last, The best parameters of preparation was gained. The structure of the sample was tested by Raman. It is completely amorphous structure through gaussian decomposition of the Raman curve. It showed that the silicon-based thin film with completely amorphous structure has the best passivation role on the substrate.