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As the currently most promising silicon-based thin-film solar cells, with raw materials inexhaustible, inexhaustible, widely distributed, and green as well as low-cost advantages, and therefore get a wide range of research and application. The structural defects of the silicon film significantly affect the performance of the thin film solar cell. The silicon thin film in the preparation process is often the presence of grain boundaries, micro-voids, dangling bonds and other defects. X-ray small angle scattering (SAXS) has been confirmed by the presence of micro-voids in the film, the grain boundary defects observed by TEM and HR-TEM, while the most common defects in the silicon thin film is a dangling bond defects. The presence of the dangling bond defect a great impact on the solar cell performance, easily become additional recombination centers for electrons and holes, so that the electron capture cross section increases life expectancy decline, affecting the stability of the battery performance. Dangling bonds in the unpaired electron, there is spin, electron spin resonance (ESR) technology measured evaporation and sputtering amorphous silicon, the spin density of 1020 cm-3, indicating that the dangling bond defect The concentration is rather high. Non-doped amorphous silicon dangling bonds in the high density (1018cm-3 or higher), the electrical performance is poor, and can not meet the application requirements of the device. Dangling bonds and related defects in silicon thin film is very necessary. This thesis uses ECR-PECVD, ArF excimer laser crystallization, frequency magnetron sputtering methods such as a silicon thin film was prepared, using a transmission electron microscope (TEM), X-ray diffraction (XRD), the Raman spectra (Raman) Fourier detection means of infrared spectroscopy (FTIR), electron spin resonance (ESR), the phase structure of the thin film, crystalline state, hydrogen content, and the dangling bond density were observed and analyzed. Understand the degree of crystallinity of the silicon thin film, hydrogen content and the density of dangling bonds on the silicon thin film studied to seek methods and processes of the stabilization treatment. Experimental results show that the use of ECR-PECVD method Si film deposited on the Si substrate, when the Ar flow rate of 70 sccm, the film suspension bond density minimum 4.42x 1016cm-3, and the hydrogen content at this time is close to 10 at. %, the degree of crystallinity of about 50%. The optimum Ar flow value of 70 sccm. Parameter conditions of the present experiment, the dangling bond density of the ArF laser surface treatment of the silicon thin film than the non-through laser processing dangling bond density reduced by nearly an order of magnitude. Prepared on the silicon in the present experimental parameters using the intermediate-frequency magnetron sputtering method to the silicon thin film was obtained in the silicon substrate (100) and ordinary glass substrate, the draw of the silicon thin film on the Si substrate obtained dangling bond density than the ordinary glass film dangling bond density is low.
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