Effects of chip thickness, solder ball shape and underfill dispensing location on plastic strain energy density of I-shaped underfilling pattern of chip scale package module.

• Main Authors: Lu, Chun-Hao, 盧浚豪
• Other Authors: Lu, Wei-Hua
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/64z2hm

碩士 === 國立屏東科技大學 === 材料工程研究所 === 106 === This study reports a commercial product of CSP module without underfill dispensed leading to the electricity failure after temperature cycling test. The CSP failure is due to the rupture of outermost solder ball at the upper right right corner of die. This study constructed a 3-D model by Solidworks and ANSYS software to numerically investigate plastic strain energy density in a I-shaped CSP module, which is dispensed underfill material, under the conditions of reflow and underfill curing process. The study investigates the degree to which the die thickness as well as underfill dispensing location and shape of solder ball influence plastic strain energy densities in a CSP module the numerical results show the addition of under material in a CSP module can reduce plastic strain energy density in the solder balls. A decrease in the die thickness and change in the shape of solder ball can obviously decrease the plastic strain energy density.