Improvement And Machanism Study On The Surface Texturing Of Monocrystalline Silicon

Texturing on the surface of monocrystalline Silicon is important in thepreparation process of solar cells. at present, alkali liquor is mainly usedin the texturing process so that pyramids structure exist on the surface ofmonocrystalline silicon.This paper analyzes the relationship between theSchr dinger equation and the defect density. It is deduced that therelationship between energy band and the forbidden band of crystal whichexists surface discontinuity in the one dimensional or two dimensional orthree-dimensional orientations and that of ideal crystal based on the theoryof electronic wave attenuation. And the surface morphology ofmonocrystalline silicon and the analysis of the theory are combined well.Besideds the article is based on the traditional alkaline etching the surfaceof the monocrystalline silicon, and study the influence of ethylene glycol,propylene glycol, ethanol and other alcohols on the monocrystallinesilicon surface morphology and test the surface reflectivity. It is found thatthe surface reflectivity is relatively low when the size of the pyramids onthe surface is small, which is usually about1~3μm. It is found that theminimum reflectance can be reduced to10.13%, and the theory isconsistent with the experiment. The theoretical results show that the defectdensity of state is relativelylower when thecrystal surface doesn’t have anydefect of structure. On the contrary, the density of defect states is relativelyhigher when the crystal surface with sharp corners or shape edges. As weknown, defect density of states is inversely proportional to the minoritycarrier lifetime. The experiment research shows that the density of defect states islower when the pyramids on crystal surface distribute nonuniformly and thevertex angle is sharp. On the contrary, the density of defect states isrelatively high when the vertex angle has arc transition and pyramids on thecrystal surface are distributed uniformly.