由於電子元件依照使用者的需求，必須達到輕薄短小、且可靠良好的目的，所以相關的研究就顯得特別重要。而因為環氧樹酯(epoxy molding compound, EMC)是最普遍使用在電子封裝產品上的材料，其所產生的缺陷，如本文所關注的：翹曲量多寡，一直是業界急需欲改善的問題之ㄧ。依據實驗及文獻，在開模之後若將產品放入一個高溫的烤箱之中，也就是所謂的後熟化製程(process of post mold cure)，產品的翹曲量會比開模時降低。所以本文利用三種軟體：InPack、Moldex3D-RIM、ANSYS，模擬出產品剛開模時的翹曲量，以及經過長時間的後熟化過程之後，其翹曲量的變化量，並加以比較是否後熟化過程可以降低產品的翹曲量。
在後熟化過程的模擬中，使用的是黏彈性質的分析，要輸入包括麥斯威爾模型、WLF公式、熱膨脹係數…等參數。而後熟化過程中仍有些許的熟化度變化，所以在整個過程中的麥斯威爾模型也會隨著溫度或是熟化度不同而不同，也就是存在著溫度轉換因子aT以及熟化度轉換因子aC的關係。而此模擬也利用些許的數學運算，將兩種轉換因子考慮至模擬之中，以期達到模擬與實驗值更加吻合的目的。

To meet customers’ demands in electronic products, all products are regarded to achieve the goals of light, small, convenient and good reliability. Epoxy molding compound (EMC) is a commonly used material in IC packaging. One of its serious defects is warpage. Warpage issue plays an important role in IC encapsulation processes to all engineers. Based on experiments and previous researches, the amount of warpage would reduce if putting the products in a high temperature (above glass transition temperature) environment such as an oven. This process is called post mold cure process (PMC). To simulate the post mold cure process, this thesis used three softwares including InPack, Moldex3D-RIM, and ANSYS to do simulation. The purpose of the simulation is to find out the amount of warpage after encapsulation process and after post mold cure process. The second purpose of this thesis is to verify PMC process can surely reduce the amount of warpage.
The PMC process simulation is a viscoelastic analysis. A viscoelastic mathematic model analysis needs a lot of parameters, such as those in generalized Maxwell model, WLF equation, coefficient of thermal expansion, shear modulus…etc. Aother important prarmeters, degree of cure of epoxy, could be different during PMC process, so the generalized Maxwell model needs to be shifted by degree of cure. The study considered both temperature shift factor (aT) and cure shift factor (aC) to build correct viscoelastic properties of EMC. After building accurate viscoelatic properties of epoxy, PMC simulation would be more specific and accurate.

[1]王智國, “IC封裝EMC材料後熟化製成黏彈模型的建立,” 國立成功大
學機械工程研究所碩士論文(2006.7)。
[2] 郭建志, “IC封裝後熟化製程材料參數數學模型之建立,” 國立成功大學機械工程研究所碩士論文(2004.6)。
[3] 蘇銘勝, “電子構裝材料在注模後烘烤中熱機械性質與數學模式之研究,” 國立成功大學工程科學研究所碩士論文(2003.7)。
[4] Injin Ko, Yungwhan Ki, “Effect of Postmold Curing on Plastic IC Packaging Reliability, ” Journal of Applied Polymer Science, Vol. 69, pp2187-2193 (1998).
[5] Spencer Chew, Ah-Chin Tan, “Evaluating the Influence of Post-Mould Cure and Additives on the Viscoelastic Properties of a Low Stress Epoxy Mould Compound,” IEEE Transactions on Electronics Packaging Manufacturing, Vol. 26, pp211-215 (2003).
[6] A.A.O. Tay, S.H. Ong* and L.W. Lee, “Finite Element Analysis of Plastic-Encapsulated Multi-Chip Packages,” IEEE/CPMT Electronics Packaging Technology Conference, pp170-176(1998).
[7] Sindee L. Simon, Gregory B. Mckenna, Olivier Sindt, “Modeling the Evolution of the Dynamic Mechanical Properties of a Commercial Epoxy During Cure after Gelation,” Journal of Applied Polymer Science, Vol. 76, pp495-508 (2000).
[8] Spencer Chew, “Thermal and Viscoelastic Characterization of Transfer-Molded Epoxy Encapsulant during Simulated Post-Mold Cure,” Electronic Components and Technology Conference, pp.1032-1038 (1996).
[9] Vernal H. Kenner, Brian D. Harper, and Vladimir Y. Itkin, “Stress Relaxation in Molding Compounds,” Journal of Electronic Materials, Vol. 26, No. 7, pp.821-826 (1997).
[10] 李輝煌, ANSYS工程分析-基礎與觀念, 高立圖書有限公司, 台北, (2005.5)。
[11] 張朝暉, ANSYS熱分析教程與實例解析, 中國鐵道出版社, 北京, (2007.5)。
[12] 胡德, 高分子物理與機械性質, 渤海堂文化事業有限公司, 台北, (2006.6)。
[13] Yeong K. Kim, “Viscoelastic Effect of FR-4 Material on Packaging Stress Development,” IEEE Transactions on Advanced Packaging, Vol. 30, No. 3, pp.411-420 (2007).
[14] 張益三, “電子構裝材料等溫等壓體積收縮行為之研究,” 國立成功大學機械工程研究所博士論文(2005.6)。
[15] 鄧湘榆,“IC封裝元件之翹曲與托盤偏移現象之研究,” 國立成功大學機械工程研究所博士論文(2007.6)。
[16] 洪立群, “IC封裝元件翹曲分析之研究,” 國立成功大學機械工程研究所博士論文(2004.6)。