晶圆尺寸级封装器件的热应力及翘曲变形

摘要

The sizes and material parameters of wafer level chip scale package(WLCSP) device would have an influence on the reliability of WLCSP. A WLCSP device of EPS/APTOS was studied by the finite element analysis software. The results show that the chip thickness, BCB thickness, the height of up pad and PCB board thickness have evident effect on the thermal stress. The thermal stress increases 21.60 MPa when the chip thickness increases from 0.25 mm to 0.60 mm. And PCB thickness influenced mainly by the warpage. The warpage of WLCSP decreases by 20% when the thickness increases PCB from 1.0 mm to 1.6 mm.%晶圆尺寸级封装(WLCSP)器件的尺寸参数和材料参数都会对其可靠性产生影响.使用有限元分析软件MSC Marc,对EPS/APTOS生产的WLCSP器件在热循环条件下的热应力及翘曲变形情况进行了模拟,分析了器件中各个尺寸参数对其热应力及翘曲变形的影响.结果表明:芯片厚度、PCB厚度、BCB厚度和上焊盘高度对WLCSP的热应力影响较为明显.其中,当芯片厚度由0.25 mm增加到0.60 mm时,热应力增加了21.60 MPa;WLCSP的翘曲变形主要受PCB厚度的影响,当PCB厚度由1.0 mm增加到1.60 mm时,最大翘曲量降低了20%.