晶圆减薄表面损伤层对断裂强度影响的研究

Study on the Effect of Surface Damage Layer on Fracture Strength after Wafer Thinning

介绍了晶圆机械磨削减薄原理、工艺过程和风险,分析了晶圆减薄损伤层厚度的影响因素,并对损伤层厚度与晶圆断裂强度的关系进行了研究。研究表明,在一定范围内,选用大目数磨轮、提升主轴转速、降低主轴进给速度能够有效减小减薄后晶圆被加工面损伤层的厚度,晶圆被加工面损伤层的厚度越小,其断裂强度越大。优化后的机械磨削减薄工艺提高了机械磨削减薄晶圆的断裂强度,降低了减薄晶圆碎片率,提升了封装可靠性。

The paper introduces the principle, process and the risk of thinning of wafer mechanical grinding, analysis the influencing factors of surface damage layer thickness after wafer thinning, an d studies the relationship between damage layer thickness and wafer fracture strength. The results show that ：within a certain range, selecting the large number of grinding wheels, increasing the speed and reducing the feed rate of the spindle can effectively reduce the thickness of the damaged layer of the processing surface after wafer thinning. The smaller the thickness of the damaged layer is , the higher the fracture strength is. Finally, we get the optimized mechanical grinding and thinning process, thereby improving the fracture strength of the wafer after thinning by mechanical grinding, reducing the probability of the wafer fragmentation , and improving the reliability of chip packaging.