Review Of Multicrystalline Silicon Wafer Solar Cell Processing

Abstract

The challenges for searching and utilizing of new and sustainable energy sources especially solar cell electricity. The major obstacle of using solar cells for electricity generation has been a much higher price when compared to the price of electricity generated from the traditional sources. The photovoltaic industry needs to put an enormous pressure and optimization at every stage of the photovoltaic manufacturing chain of multicrystalline silicon wafer solar cell processing in order to reduce cost. Processing of multicrystalline silicon solar cells is starting by silicon wafer preparation, etching and texturing, saw damage etching, surface texturing, phosphor diffusion & edge isolation, phosphor diffusion, edge isolation, silicon nitride deposition for antireflection coating, and metallization process that consist of screen printing ag front side, screen printing of al back side, drying and firing and formation al back surface contact. Mechanical stability of silicon wafer became a serious issue due to reduction of wafer thickness, so probability for wafer to breakage is high; investigate the mechanism of wafer breakage is important to reduce breakage. The present of micro cracks reduces the mechanical strength of wafer significantly and wafer breakage will increase, because crack will start from the existing micro crack and that will propagate easier with presence of the stress. Mechanical stability is increase significantly after the etching process; on the other hand the screen printing process will reduce wafer strength. Etching of saw damage, that is induced during wafer slicing, and metallization of the surfaces are 2 crucial processing steps in the manufacturing of mc-silicon solar cells