偏振激光散射检测单晶硅片磨削后的亚表面微裂纹

Detection of subsurface microcracks after grinding of single crystal silicon wafer by polarized laser scattering

单晶硅片在磨削过程中会不可避免地产生亚表面微裂纹损伤。采用偏振激光散射检测方式对单晶硅片亚表面微裂纹损伤进行无损检测,得到其对应的检测信号强度,再利用有损检测方式对单晶硅片亚表面微裂纹损伤体积密度进行定量测定,建立检测信号强度与体积密度之间的对应关系并进行试验验证。结果表明:采用偏振激光散射检测方式得到的硅片亚表面微裂纹体积密度与有损检测方式的比较,其相对误差在10%以内;在不影响生产效率的前提下,偏振激光散射检测方式能无损、准确、快速地检测硅片的亚表面微裂纹。

In grinding process,there will inevitably produce subsurface microcrack damages on the monocrystalline silicon wafer.The subsurface microcrack damages of monocrystalline silicon wafer are nondestructively detected by the polarized laser scattering method,and the corresponding signal strength is obtained.The volume density of subsurface microcrack damages is quantitatively determined by using the destructive detection method,and the relationship between the detection signal strength and the volume density is established and verified by experiments.The results show that the relative error of the volume density of the subsurface microcracks obtained by the polarized laser scattering method is within 10%compared with the volume density obtained by the damage detection method.The polarized laser scattering method can detect the subsurface microcracks of silicon wafer nondestructively,accurately and quickly without affecting the production efficiency.