激光在PERC晶硅电池中背面点接触电极制备中的应用

Application of Laser Technique for Fabrication of Rear Dot-contact of PERC Crystalline Silicon Solar Cell

在经过Al2O3全钝化发射极钝化局部背接触(PERC)结构电池的背面实现良好的接触电极一直是制约着PERC高效电池向产业化推广的重要因素之一。本文采用532 nm激光烧蚀背面钝化介质层方法和传统的光刻工艺来实现背面电极的局部接触,并对两种方法进行详细的比较与分析。对激光烧蚀和激光烧结两种不同的局部接触电极制备方式进行了对比,发现激光烧蚀是更为适宜的工艺方式。相较于激光烧结,以激光烧蚀方式制备的电池的串联面接触电阻从10.7Ω.cm2降到1.24Ω.cm2,效率从4.2%提高到10.7%。

One of the factors restricting the appliance of high-efficiency passivated emitter and rear cell （ PERC ） -type solar cell to the industrial silicon solar cell is that the formation of good ohmic contacts on the rear side of PERC-type solar cell passivated by AlE O3 film. This work focuses on the formation of rear local contacts instead of high efficiency by using laser ablation with 532 nm wavelength and conventional photolithographic technique. The results of the contact formed by these two methods are compared and analyzed. In addition, we compare and analyze the rear local contacts formed by laser ablation and laser firing using 532 nm line laser. The results suggest that the laser ablation can provide better contacts in the PERC-type solar cell. The contact resistance of the solar cell using laser ablation technique is reduced to 1.24 Ω.cm2from 10.7 Ω.cm2 using laser firing method, and the efficiency is enhanced from 4.2% to 10.7%.