由於封裝體朝向高散率,高I/O數,微小型化,所以強化散熱性能一直是很重要課題。本文使用ANSYS商用軟體, 建構詳細的網格, 在自然對流與強迫對流環境下,針對FC-PBGA封裝體裝配不同散熱器 進行精密的熱傳數值模擬分析,求解封裝體內溫度分佈。並進一步,比較它們的散熱性能。這個詳細的網格(detailed mesh) 含蓋熱通孔、錫球、與墊片、散熱銅層、防護罩、散熱器、PCB等重要元件, 使得網格更能接近實際封裝體, 使得模擬結果更準確。最後,針對影響封裝體散熱性能的各種變數(凸片長度、凸片厚度、凸片數目、支撐架厚度、凸片導熱係數、底板厚度與風速等因子)進行靈敏度分析。

The trend in microelectronics is toward increasing higher input/output, higher component density and higher electrical performance, which makes thermal enhancement to package performance an increasingly important issue. Under natural and forced convection conditions, three-dimensional (3D) finite element simulation is used to study the thermal performance of a flip-chip plastic ball grid array (FC-PBGA) assembly with various heatsink attached to the top surface of the assembly. The finite element model of this assembly is detail enough to include key packaging elements such as bump, solder balls, substrate, printed circuit board (PCB), vias and ground planes for both signal and power. 3D finite element simulation for temperature distribution is performed under varying values for the following variables: with/without heatsink/lid, with/without lid, fin length, fin thickness, fin number, Base height, heatsink conductivity and airflow speed. Thermal resistance is calculated to characterize and compare the thermal performance of the various package configurations.

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