The Design Analysis and Delamination Prevention for a Leadframe Type 3D Stacked Package

• Main Authors: Chieh-pei Chen, 陳潔蓓
• Other Authors: Yeong-shu Chen
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/42099767843552493809

碩士 === 元智大學 === 機械工程學系 === 91 === The three-dimensional stacked package is one of a multi-chip package that the dies are stacked vertically. The delamination of the package is often observed during the manufacturing and using environments. The study focuses on designing a lead frame type 3D package with an objective in preventing the delamination and obtaining the best design parameters through a serious of analyses and experiments. The study starts from the process of patent analysis and verification. With the aid of finite element method (FEM), it is then possible to investigate the best design parameters and create a new design for the delamination prevention. Some of the proposed design is also verified experimentally by using shadow moiré method by simulating the IR-reflow process. A theoretical calculation is then compared with the experimental results. The FEM method shows that with the die-pad down to the surface of the molding compound, and when the width of die pad and the chip are the same, the resulting stresses at the interface will be minimum. Also, the stress is minimum when with thicker upper chip and thinner bottom chip. It is concluded that both of them can prevent delamination effectively.