溫度變化對電子構裝之熱應力分析

Abstract

本研究的主要目的在於探討散熱強化型塑膠球柵電子構裝受晶片溫度循環負載下所衍生的破壞現象。本文利用數值模擬軟體ANSYS分析金線、構裝各元件介面及錫球的熱應力，並用局部對流熱傳係數法來模擬流體與固體邊界的共軛熱傳問題。結果顯示，與散熱片接觸介面的某些位置會有破壞產生，並預測晶片轉角處和最外側錫球與基板接合處會隨著晶片溫度循環次數的增加分別產生裂縫和疲勞破壞。

The aim of this study is to investigate the failure behavior induced by thermal cyclic loading of the Thermal -Enhanced PBGA. In this study, thermal stress analyses of Au wire, interfaces of different materials and solder balls are carried out by using ANSYS finite element simulation code. In addition, local heat transfer coefficients distribution is used to simulate conjugate heat transfer problem on the package surfaces. Results show that there are defects happed in some positions contacted with heat spreader. Cracks in the chip corner points and fatigue failure in the edge balls are also predicted by increasing thermal cyclic loading times.