Study On The Growth Of SnO / CdO Nanocrystals On The Surface Of Crystalline Silicon Cells And The Performance Of Composite Batteries

Currently, crystalline silicon solar cells still remain as the mainstream in photovoltaic industry. Because of its mature process and abundant resources, silicon solar cell has occupied the market for a long time. While in recent years, researches on efficiency enhancement of silicon solar cells have been extremely hot. In this research, metal-oxidesemiconductor layers with different bandgaps were fabricated on the top of polycrystalline silicon., and through treatments like FESEM, UV-Vis-NIR Spectrophotometer, minority carrier lifetime measurement and so on, optical and electrical properties could be analyzed through different angles.In this research, we used two different deposition methods to deposit two metallic salt solutions on the surface of crystalline silicon. Firstly, dipping deposition was used to deposit Cd²⁺ on washed silicon wafer. Through changing deposition time, we could control the thickness of deposited layer and then compare the difference of performance. After those measurements we can find out that the deposited layer performed a best surface morphology and terrific effect of restraining of carrier recombination when the thickness of deposited Cd O layer was about 20 nm. Besides, the research was also conducted to discuss different influences on composited solar cell by changing solvent system. In addition, Chlorate tin was used as material to apply in this part of research. With spin-coating method, SnO₂ layers with various morphologies were prepared on silicon surface. Here we changed the deposition times and temperature of thermal treatment to illustrate the effect on optical and electrical performance by different morphologies. As a result, firstly, deposition numbers have a strong impact on morphology of SnO₂. When SnO₂ layer formed concave shape, the composited solar cell obtained the best absorption performance. Besides, if the time was too long and temperature was too high, thermal treatment was able to take deep damage to composited solar cell.According to the order of bandgaps, we developed SnO₂/CdO/Si multi-layer composited solar cell. This composited solar cell not only occupies a good absorption performance and spectrum-widening property of single-layer composited solar cells, but also obtains initiative separation effect between electrons and holes due to its unique structure. And thanks to this effect, carrier lifetime value of multi-layer composited solar cell is 22% higher than that of single-layer composited cells. And the PCE is 21.9% higher compared to blank Si solar cell.