Research On Polysilicon Laser Texturing Process And Key Technologies For Parallel Processing Equipment

Texturing is one of the important means to improve the photoelectric conversion efficiency of crystalline silicon cells.At present,chemical texturing is generally used,and the reflectance is above 10%.Further reducing the reflectivity has become a research hotspot,and the laser texturing anti-reflective effect is better,and it is urgent to optimize its process plan and further improve the texturing efficiency.In order to solve the bottleneck problem of low efficiency of laser texturing,this paper proposes a parallel production method of the perforation laser aperture hole sub-region,and optimizes the whole process efficiency based on the laser texturing process,and the equipment is developed.The specific research contents are as follows:Based on the finite difference time domain(FDTD)method,the microstructure parameters of the microstructure were simulated and optimized,which provided a theoretical basis for the preparation of high-efficiency anti-reflective surface.The anti-reverse theory model based on the subsequent process is established.The finite-difference time-domain method is used to simulate the electric field distribution of the incident light interacting with the array hole.The influence of the geometric parameters of the array hole on the reflectivity is studied.Studies shows that the array hole has the lowest reflectivity when the hole depth is constant and the hole diameter and center distance are equal to the spot diameter.Optimized the laser texturing process parameters,and carried out the experimental study on the preparation of the array hole by picosecond laser.Based on the single-point etching experiment of picosecond laser,the influence mechanism of laser process parameters on laser texturing depth was studied to improve the quality and efficiency of texturing.The experiment of preparing the picosecond laser array hole surface was carried out,and the mechanism of the array hole pitch on the surface reflectance and the photoelectric conversion efficiency of the crystalline silicon cell was studied.Finally,made a uniform surface with a reflectivity of 5.17% and the corresponding battery photoelectric conversion was performed.The efficiency is 18.45%.Aiming at the bottleneck problem of low efficiency of laser texturing,the whole process of the process is optimized,and the parallel processing method of sub-area is proposed,and its equipment is developed.For the problem of low efficiency of the laser texturing process,the whole process of the texturing process is optimized.Reduces the process of insert and separate silicon,etc.and shortens the pickling corrosion time.Aiming at the problem of low efficiency of laser processing one by one and the difficulty of processing large-area silicon wafers,a parallel processing method of multi-beam parallel texturing and sub-region galvanometer is proposed,and parallel processing equipment is developed.Significantly improve laser texturing efficiency.Analyze the key technologies in the scheme of sub-regions multi-beam parallel processing,and develop parallel optical system and automated wafer transport system.Aiming at the multi-beam parallel processing equipment scheme in sub-region,the parallel optical path system was developed,which realized the laser sub-region processing and parallel beam processing,which significantly improved the laser texturing efficiency.The R&D automated conveying system of wafer realizes the automatic feeding of silicon wafers,online pickling,automatic detection of the production process of inserts,and promotes the industrial application of laser texturing.