激光刻蚀柔性薄膜太阳电池复合背反射层的研究

Laser etching of compound back reflector of flexible thin film solar cell on polyimide

柔性聚酯膜衬底薄膜电池通过激光刻蚀等工艺形成集成串联,激光刻蚀柔性薄膜太阳电池复合背反射层(Ag/ZnO)是其中的重要工艺。首先对聚酰亚胺(PI)、Ag、ZnO材料的光学特性进行了分析,然后采用1 064nm脉冲激光与532nm脉冲激光分别对柔性薄膜太阳电池复合背反射层进行刻蚀研究。通过改变重复频率、激光功率、扫描速度和焦点位置等参数,分析了激光刻蚀物理机制,获得了好的刻蚀效果。结果表明,1 064nm纳秒脉冲激光更适合刻蚀柔性PI衬底复合背反射层Ag/ZnO,在激光功率860mW、刻蚀速度800mm/s和重复频率50kHz下,获得了底部平整、两侧无尖峰的刻线,刻线宽为32μm,满足柔性薄膜太阳电池集成串联组件的制备工艺要求。

The monolithic series interconnection of flexible thin film solar cell on polymer （PI） substrate is obtained by laser etching and other technology, and laser etching of compound back reflector （Ag/ ZnO） on polyimide is very important. The optical characteristics of polyirnide and Ag/ZnO are analyzed. Pulsed lasers with wavelengths of 532 nm and 1064 nm are used for comparison. The influence of various laser parameters like laser power,pulse overlap, etc. ,is discussed and the parameters are optimized. Laser-etching mechanism is analyzed. The experiments show that 1 064 nm pulse laser is more suitable for laser etching of Ag/ZnO on PI. At laser power of 860 mW,etching speed of 800 mm/s and repetition frequency of 50 kHz,a very good etching line with 32/um width is obtained.