近年來，電子產品除了追求輕薄短小、低成本以及優越的電性能和熱性能之外，更需要具備多功能與高容量等特性以滿足市場需求。因此，滿足上述目標的3D堆疊封裝技術越來越受到重視。故本文將針對可攜式電子產品大量使用的QFN構裝體結合3D堆疊封裝技術，進一步研究堆疊晶QFN構裝體。
本研究採用ANSYS9.0套裝分析軟體進行分析，並且根據JEDEC規範將堆疊晶QFN構裝體施予-40℃~125℃的溫度循環負載。錫膏選擇亞蘭德模型，並且使用Coffin-Manson疲勞壽命預測公式來計算堆疊晶QFN構裝體錫膏的疲勞壽命。
本文針對溫度循環範圍的振幅、溫度循環範圍的平均溫度、晶片尺寸、晶片厚度、印刷電路板厚度、印刷電路板熱膨脹係數、封膠熱膨脹係數、錫膏的外觀形狀、晶片墊熱膨脹係數、晶片墊楊氏模數、黏晶膠熱膨脹係數等因子進行單一因子分析，以評估各因子對封裝結構疲勞壽命的效應。最後將上述各因子利用田口品質設計法找出最佳的參數組合，有效地改善堆疊晶QFN構裝體之可靠度。
由單一因子分析結果顯示，藉由縮小溫度循環範圍的振幅、較小的晶片尺寸、較薄的印刷電路板、降低晶片墊熱膨脹係數、降低印刷電路板熱膨脹係數以及增加封膠熱膨脹係數皆能有效提高堆疊晶QFN構裝體的疲勞壽命，其餘因子對堆疊晶QFN構裝體疲勞壽命的影響性並不大。最後，利用田口品質設計法所得最佳製程參數之構裝體疲勞壽命為8124次，而原始製程參數設計之構裝體疲勞壽命為1926次，疲勞壽命約提昇4.21倍，因此有效改善堆疊晶QFN構裝體之可靠度。

In addition to the qualities of light-weight, mini-size, low costs, and excellent electrical and thermal performances, electronic products are further required to have qualities such as multiple functions and high capacity to meet the demand of the market in recent years. With this view, the 3D packaging technology facilitated to above purposes has been gradually noticed. By incorporating with the 3D packaging technology, this study focuses on quad flat lead-free package which is widely used in portable electronic products to further analyze the stacked die QFN package.
This study adopts ANSYS9.0 software for analysis. Based on the JEDEC code, the stacked die QFN is loaded by a temperature cycle of -40℃~125℃. The solder paste is assumed to be Anand’s model. The Coffin-Manson fatigue life formula is applied to predict the fatigue life of the solder paste in the stacked die QFN package.
The single-factor experiment is conducted to predict the impact on the fatigue life of the stacked die QFN in which factors such as the amplitude of temperature cycling range, the average temperature of temperature cycling range, die size, thickness of die, thickness of PCB, CTE of PCB, CTE of mold compound, CTE of adhesive, the shape of solder paste, CTE of die pad and Young’s modulus of die pad are analyzed. Accordingly, the Taguchi Method is applied to obtain the optimal parameter combination to improve the reliability of the stacked die QFN package.
The single-factor analysis shows that the solder fatigue life increases along with the reduction of the amplitude of temperature cycling range, die size, thickness of PCB, CTE of die pad, CTE of PCB as well as the increase of CTE of mold compound, Thus other factors have no significant effects on the solder paste fatigue reliability.
Finally, the optimal design derived from the Taguchi Method results in the fatigue life of 8124 cycles which shows a 4.21 times increase compared to 1926 cycles of the original design. Therefore the reliability of the stacked die QFN module package has been efficiently improved.

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