【摘要】 相比其他加工方式,激光加工具有割线小,切割速度快,割缝边缘垂直度好,切割时无机械应力等优点。本文结合国内外激光薄膜加工研究结果,从激光与物质相互作用的角度出发,建立激光切割硅薄膜太阳能电池的理论模型。用有限元法(FEM)求得柱面坐标下热平衡方程的数值解。讨论激光波长,能量密度,脉冲重复频率,光斑形状与薄膜损伤阈值,切割速度,以及切割质量之间的关系。结合理论分析与实验,优化了激光器的设计,选择氪灯抽运的λ=532 nm Nd:YAG激光器,采用KDP倍频,声光调Q方式工作,给出了重复频率与切割速度的配对关系,提出用柱面聚焦系统代替球面聚焦系统,从而减小垂直于割缝方向的热影响,并有利于切割速度的提高。更多还原

【Abstract】 Laser scribing has been widely used in semiconductor process for its various advantages. A discussion based on the most recent international research result relating to semiconductor fllrn scribing has been developed. A transient combined nonlinear optical -thermal model for single laser pulse incidence on a multilayer film -glass substrate. Finite Element Method (FEM) is applied to solve the model. According to the solution, the effects of laser wavelength, energy destiny, pulse duration and the style of focusing on the ablation threshold of film and the scribe quality are mainly discussed. The wavelength of laser beam was found to play the crucial role on the process quality and the energy destiny, while the pulse duration has effects on them.更多还原