Thermal and Warpage Analysis for TSOP-IC Packages

• Main Authors: Yi-Bin Lai, 賴宜彬
• Other Authors: Hsin-Yi Lai
• Format: Others
• Language: zh-TW
• Published: 2000
• Online Access: http://ndltd.ncl.edu.tw/handle/70913701301383338679

碩士 === 國立成功大學 === 機械工程學系 === 88 === The increase in circuit density and decrease in volume size in IC packages have emerged as an inevitable trend in recent years. As a result, the heat dissipation problem becomes a critical issue for IC packaging applications. The effect of geometric shapes and packaging materials on thermal performance of the chip is one of the major research issues. The associated thermal expansion mismatch between various constituents of packaging materials is another issue. Thermal deformations resulted from large temperature difference in the processes of cooling and IR reflow often lead to thermal crack and delamination, and therefore, is also important issue for IC packaging applications. Various TSOP (thin small outline package) modules are selected and used as basic modules for comparative studies in this thesis. Three-dimensional eight-node thermal brick element models are developed and applied to build a finite element TSOP model. The model is used to evaluate thermal properties and deformation of the packages with different geometric shapes, packaging materials and process parameters. In order to improve the modeling accuracy, a modified iterative scheme for convection coefficient re-evaluation is employed. The temperature dependent CTE (coefficient of thermal expansion) based elastic-plastic EMC model is also presented for thermal deformation analysis. Numerical modeling solutions obtained from this study are used to compare with experimental results. Both numerical and experimental solutions are found agreed well with each other. These results can be used to predict thermal performance and the warpage of TSOP packages. They can also be used for package redesign, thermal failure prevention and package reliability enhancement.