Studies On The Double Layer Anti-refrective Coating Solar Cell Mass Production Process Technology Based On Polysilicon

The effect of solar cell is more and more important with energy crisis getting more and more urgent,It is demanded to improve current manufacturing process to decrease electric power generation cost. We have got several access to cost down, one, the raw material cost can be decreased; another, solar cell conversion efficiency is promoted by improving process without increasing manufacturing cost. It is the key piont for promoting solar cell efficiency that the loss of the light reflected,transmitted and photon-generated carrier recombined should be decraesed. Currently on the market, crystal silicon solar cell mainly uses monolayer silicon nitride as antireflection coating,that the reflectivity is reduced to 9% from 350nm~1100nm optical spectrum. The reflectivity, abtained theoretically by calculation, can be reduced further.It is only based on current equipment and manpower that double layer antireflection coating can gain solar cell efficiency 0.2% or more. Though it is gained just 0.2%, it is a great progress on manufactruring and electric generation cost down. It is studied on SiON/SiN double layer and double silicon nitride antireflection coating process parameter in this paper1) It is found that how the silicon nitride despostion rate andphoton-generated carrier life time is impacted by total gas flow,pressure, temperature by lots of experiment. It is the guidance for double layer desposition process2)According to optical interference theory in thin film, the efficiency of antireflection monolayer coating solar cell has been promoted by double layer antireflection, attribute to its so wind and good antireflection performance on optical wave from 300~1100 nm, reflectivity for double antireflection coating with equivalent admittance is caculated through evaluation function of weighted average reflectivity. Monolayer and double layer antirelfection reflectivity profile is drawn with Matlab and Excel 2007 function progamme.It is found that how the reflectivity of double antireflection coating is influenced by varying thickness and refractive index of each layer, through simulation DOE. The best combination of thickness and refractive index of each layer has been got.3) SiON/SiN double layer and double layer silicon nitride antireflection coating solar cell have been obtained, Comparing reflectivity, quantum efficiency and electrical properties, the SiON/SiN double layer and double layer silicon nitride antireflection coating solar cell has got +0.1~0.15 A better short-circuit current, 2~3mv better open circuit voltage, In all, it has got higher efficiency 0.2~0.3% than monolayer antirelfection coating solar cell. it is conclusion that double layer antirefletion coating have so wind and outstanding antireflection performance, as to promote mass production solar cell effeiciency effectively...