The Process Research Of Black Silicon Solar Cell

At present, in order to reduce the production cost, the thinner silicon wafer is the development trend of crystalline silicon solar cell. Due to the wafers become thinner, especially when the passivation effect is good, light absorption becomes a crucial factor. Therefore, we need to maximize light absorption of the silicon substrate to ensure high efficiency. Black silicon technology is to make the silicon wafer surface become nanostructures. Within a wide range of spectrum, the absorption of incident light is close to95%.In this paper, PⅢ (Plasma immersion ion implantation) technology is used to fabricate polycrystalline black silicon and it can achieve low cost manufacturing. The principle is that the silicon wafers directly immersed in plasma, and then add the negative bias on it. As a result of the formation of sheath layer on the surface of silicon wafer, it will be injected reactive ion. At the same time, the reactive ion will react with silicon to form black silicon. This paper adopts self-built equipment system to fabricate black silicon, and then study the optimum technological conditions. It also compares the efficiency of black silicon solar cell and conventional solar cell, indicates that the efficiency of black silicon is increased0.3%on average.Finally, owing to the nanostructures, black silicon has large superficial area and a large number of surface states, and also makes the electronic state and band structure change, so this article is to study on a series of surface passivation. Hoping to discovery a method of effectively reduce the silicon surface activity and improve the minority carrier lifetime. Experiments using traditional plasma enhanced chemical vapor deposition (PECVD) technique to grow silicon nitride thin film on silicon surface, mainly study the gas ratio, deposition temperature and deposition time effect on antireflection and passivation; it also studies the influences of deposition conditions on the battery quantum efficiency.