Laser scribing system for a-Si thin film solar cell preparation

The laser scribing process for a-Si(amorphous silicon) thin film solar cell preparation requires the line width of 30 μm～50 μm,the dead zone of less than 300 μm in size,and the compliance of line depth with the process requirements.Thus,the high beam quality of the laser is required,as well as the high imaging quality and wide focal depth of the optical system.A laser scribing system with a single laser and four-way light splitters was designed.With the designed laser scriber,a laser scribing test was done on a 1 400 mm×1 100 mm×3.2 mm glass substrate.The widths of the scribing lines P1,P2 and P3 were 35 μm,50 μm and 45 μm,respectively,the dead zone(distance between P1 and P3) was 287 μm,and their final depths were 0.98 μm,0.24 μm and 0.58 μm respectively.The results show that the widths and depths of the scribing lines meet the requirements of thin film solar cell preparation process.