Crystalline silicon material is the most important photovoltaic material, the nature of a metallic luster with a grey-black solid, high melting point (1410), hardness, brittle, at room temperature chemical properties are not active. It has a market for crystalline silicon: a 75mm diameter silicon chip that can integrate tens to hundreds of thousands or even millions of components, forming microelectronics that gave rise to microcomputers, microprocessors and so on. Due to the current development of information engineering, silicon is mainly used in microelectronics technology. Is given priority to with silicon thyristor power semiconductor devices, components grew, compared with silicon transistor integrated circuits on the contrary, in a diameter of 75 mm silicon wafers, can only do a bear a few kA current and kV voltage components, the components to infiltrate electronics, power, control, three areas to form a new discipline - power electronics. In order to adapt to the development of large scale integrated circuit, monocrystalline silicon forward large diameter, high purity, high uniformity, development in the direction of no defects. The maximum wafer diameter has reached 150mm, and the high purity silicon in the laboratory is close to the theoretical limit purity. The commonly used solar cells are silicon cells. If you cover one square meter with silicon solar cells, you get 100 watts of power. With stable performance, high conversion efficiency, small size and light weight, monocrystalline silicon solar cells are very suitable for power supply on spacecraft. Skylab, a large U.S. spacecraft, has four solar panels, which are composed of 147,840 8-square-centimeter arrays of single-crystal silicon solar cells that generate about 12KW of power. The rate is above 90%, and will remain the mainstream material for solar cells for a long time to come.