Structural Analysis and Performance Improvement of Flip Chips in Thermal Bonding Processes

• Main Authors: Chu-Yu Yeh, 葉楚榆
• Other Authors: Chung-Li Hwan
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/51472338985973454213

碩士 === 逢甲大學 === 機械工程學所 === 93 === This research is aimed to investigate the stress distribution in the bumps on a narrow-long flip chip under thermal bonding process. In thermal bonding process, the flip chip bears not only a downward pressure from the thermal head, but also a thermal loading via heat transfer. This causes the stress variation in the bumps more complex. The non-uniform stress distribution in the bumps on the chip will bring about a non-uniform deformation and/or a residual stress distribution, and thus affects the electric conductivity of the bumps on the chip. This research analyzes the stress distribution in the bumps on a narrow-long flip chip under thermal bonding process by ABAQUS, and investigates the effects of variation of parameters on the stress distribution in the bumps. It is shown from the computed results that the stress value of input-sided bumps is larger than that of output-sided ones. If the total area of input-sided bumps equals to that of output-sided bumps, then the stress difference in between can be reduced to the smallest. The effects of changing the column numbers of lateral sided bumps or the thickness of chip on the stress distribution are not obvious.