紫外激光刻蚀单晶硅片工艺的试验研究

Experimental Research on Monocrystalline Silicon Etching by Using UV Laser

紫外激光刻蚀单晶硅片时,热传导作用和等离子热效应等多种作用机理共同决定刻蚀效果,热传导作用导致材料的熔化和气化,等离子体热效应导致材料破碎和抛出。从理论上分析各种作用机理中相关工艺参数的作用,并针对不同的工艺参数进行测试,综合分析各个工艺参数在刻蚀过程中对刻蚀质量的影响,在此基础上,为寻找最优刻蚀工艺参数和最佳刻蚀效果提供指导原则,通过试验验证指导原则的合理性,并得到刻蚀硅片的最优刻蚀工艺参数。试验可知,单个激光脉冲的功率密度和频率对槽深和槽宽影响最大,单个激光脉冲的功率密度和扫描速度对槽的成形质量影响最大。

When etching monocrystalline silicon with UV laser, several action mechanisms codetermine the etching result, such as thermal conduction and plasma effect. Thermal conduction leads to material melting and evaporation, plasma effect leads to material breaking and throwing-out. Analyses theoretically the role of relevant process parameters in every action mechanism, tests respectively the key process parameters, ultimately obtains the relationship between the optimal process parameter and the best etching quality. On the basis of analysis and test, the guiding principle is obtained which is used to guide the experiment on how to get the best etching quality. The result shows the guiding principle is reasonable, and the optimal process parameter of etching monocrystalline silicon is achieved. The experiment shows, the power density of single pulse and frequency determines the slot’s depth and width, both power density of single pulse and scanning speed determine the shape and surface quality of the slot.