What is the production process of solar batteries?

The production process of solar storage batteries, rich in silicon silicon, is one of the most abundant materials on our planet. Since scientists discovered the semiconductor properties of crystalline silicon in the 19th century, it has changed almost everything, even human thinking. At the end of the 20th century, silicon can be seen everywhere in our lives and its uses. Crystalline silicon solar batteries have been industrialized the fastest in the past 15 years. Processing process The processing process can be roughly divided into five steps: a, the purification process b, the drawing process c, the slicing process d, the battery making process e, and the packaging process. Taking monocrystalline silicon as an example, the processing process can be divided into: process one, silicon wafer cleaning and flocking surface treatment: removing surface oil and metal impurities) removing the cutting damage layer on the surface of the silicon wafer) making suede on the surface of the silicon wafer, Form anti-reflection texture and reduce surface reflectivity) Using the anisotropic corrosion of Si in the dilute NaOH solution, a 3-6 micron pyramid structure is formed on the surface of the silicon wafer, so that the light on the surface of the silicon wafer will undergo multiple reflections and reflections. Refraction, adding light absorption) Step two, diffusing the single/double-sided liquid source phosphorus of the silicon wafer to make an N-type emitter region to form the basic structure of photoelectric conversion: PN junction. The liquid POCl3 molecules enter the furnace tube under the N2 carrier gas. After a series of chemical reactions at high temperatures, phosphorus atoms are replaced and diffused into the surface of the silicon wafer, activated to form N-type dopants, and form PN junctions with P-type substrates. The important chemical reaction formula is as follows: POCl3+O2(rarr)P2O5+Cl2P2O5+Si(rarr)SiO2+P Step 3: Plasma cuts to remove the short-circuit ring formed around the silicon wafer after diffusion) Step 4: Remove phosphosilicate glass to remove silicon The surface oxide layer and the phosphosilicate glass formed during diffusion (phosphosilicate glass refers to the SiO2 layer doped with P2O5). Step 5, PECVD purpose anti-reflection + passivation: PECVD is plasma enhanced chemical vapor deposition equipment, PlasmaEnhancedChemicalVaporDeposition) to produce SiN film (~80nm) that reduces the reflection on the surface of the silicon wafer) SiN film contains a lot of hydrogen ions, and hydrogen ion implantation In the silicon wafer, the purpose of surface passivation and bulk passivation is achieved, the recombination of carriers is effectively reduced, and the short-circuit current and open-circuit voltage of the battery are increased. Disclaimer: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous post: What are the advantages of lithium iron phosphate battery packs?