| 摘要 |
The invention relates to a method for producing a purified crystalline silicon substrate in order to produce photovoltaic cells. Conventional technology for sawing a silicon ingot leads to a significant loss of materials and a variability in the doping rate of the silicon which varies depending on the position in the ingot. The invention describes a method that does not lead to material loss and produces completely planar substrates. According to the invention, a silicon substrate is produced by floating the liquid silicon 2 on the surface of a liquid bath 10 of fluorides of at least one chemical element from column II of the periodic table, and then by cooling the layer of liquid silicon until said layer of silicon solidifies and crystallises. According to the invention, the silicon 1 is melted in a pot 20 which is discharged onto the liquid bath of fluorides. The formerly liquid and now solid silicon thus flows over the surface of the bath of molten fluorides. A strip of crystallised silicon 4 is then extracted and cut along to the desired shape for the substrates. According to a development of the invention, the silicon is carried in powder form on the surface of the bath of molten fluorides. <b/> |
