The investigations of an efficient multi-crystal silicon solar cell

Abstract

This research work is on the possibilities of an efficient multi-crystal silicon solar cell. The research was carried out on cheaper methods of obtaining multi crystal silicon that is of electronic grade, having background theory in semiconductor physics, the principle of p-n junction, separation of carriers by the p-n junction, multicrystalline silicon production. Various materials and efficiencies for solar cells were investigated in this project. The researchers found out that Metallurgical grade silicon (MGS) is obtained by reduction of sand (Sio₂) with coke (coal) in an arcfurnace. Single crystal silicon may be grown by a number of methods. In the common Czochralski process a single crystal is drawn slowly out of a melt. In the float zone process a single crystal is gradually formed from a polycrystalline rod by passing a molten zone through it. This is more costly but produces higher purity material. In either case the dopant (usually boron) is introduced during growth to produce a p type crystal. The solid crystal is sliced into wafers and etched to smooth the rough surfaces.At the end, the result shows that typical module efficiencies for screen-printed multicrystalline solar cells are around 12% to 14%. The polycrystal Silicon has an overall efficiency of 14%. The polycrystal silicon often used because they are cheaper than single crystal silicon, which has efficiency of about 20%.In some of the solar panel that used multicrystal silicon, the main advantages are that they are less expensive, and these panels can be purchased by the less developed economy.