隨著終端市場的需求，晶片的功能設計與輸出的功率日亦強大，這代表電子封裝的密度會不斷的升高，相對的單位體積內所產生的熱量會越來越大，當晶片的工作溫度超過所設計的溫度時會造成部分的功能失效，嚴重的會使整個晶片燒毀沒有辦法繼續工作；這樣的趨勢會為封裝結構的散熱與信賴性能力帶來嚴峻的考驗。
本文利用QFP (Quad Flat Package)封裝結構體搭配外露式散熱片在不改變現行封裝製程下修改封裝體內部散熱片的結構以達到封裝體散熱與信賴性能力的提升；本研究分成三個主題來做探討：(1) 降低封裝體內部材料間分層的問題，增加材料間的結合性；(2) 降低封裝結構對外部環境的熱阻值，利用TIM ( Thermal Interface Material ) 材料取代封裝結構體內空氣的介層；(3) 延伸TIM材料的應用，利用不同的TIM材料種類與TIM材料的厚度來做熱阻值能力的交叉比對。
本研究結果發現，降低內部材料間分層的問題為首要關鍵，分層即代表封裝體內部材料間有空氣存在，這是造成封裝體內部熱阻值升高的主要問題；TIM材料的應用可以降低封裝結構內部分層問題的產生增加結構信賴性能力，在材料厚度上的差異為越薄對於封裝體熱阻的降低有著正向的關係，在不同種類的TIM材料會有著介面熱阻的問題產生出來。

To follow the terminal market requirement, the function and efficiency demands of chips increase. This causes high density electronic packaging, which raises the heat dissipation. If the chip working temperature is over the design limit, it results in the function failure and the chip burnout. This trend will bring severe challenge to the packaging reliability and heat dissipation ability.
In this work, the assembly structure includes Quad Flat Package (QFP) and an exposed type heat slug. Only the heat slug structure is modified and no other change is made in the assembly process. This modification is expected to enhance the thermal and reliable capability. There are three subjects in this study: (1) reduce the delamination problem by increasing the adhesion between materials; (2) reduce the thermal resistance in the packaging structure by using the thermal interface material (TIM) to avoid the formation of air gap in the structure；(3) analyze the TIM effects on the thermal resistance for different TIM materials and thicknesses.
From the study results, it can be found that the delamination is the key problem, which means there exists air gap. This results in the increase of thermal resistance. Appropriate TIM applied to the heat slug structure can enhance material interface adhesion and reduce the delamination risk in the assembly process. This could decrease the thermal resistance and enhance the reliable capability. However, it should be noted that the application of TIM could induce extra interfacial thermal resistances.

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