應用有限元素法於COF-ILB共晶接合技術之參數化設計

Parametric Design of COF-ILB Eutectic Bonding Process by Finite Element Method

黃奕銓(Yi-Chuan Huang)

指導教授 ： 劉德騏

國立中正大學/工學院/機械工程學系/碩士(2013年)

摘要

覆晶軟板(Flip-Chip-on-Film, FCOF)技術在內引腳壓合(Inner Lead Bonding, ILB)製程中包含熱壓溫度、熱壓時間、凸塊尺寸、引腳尺寸、引腳鍍錫量、以及壓合力量等製程參數，其接合情況將直接影響產品的良率與可靠度。一般而言，較差的良率以及可靠度大部分因為製程引發的熱變形以及應力/應變行為所造成的，而這些行為通常會導致不同的破壞模式。本研究主要目的在於建立一個最佳化製程參數設計，文中將考慮內引腳接合處幾何的變化以及接合過程溫度傳遞現象，並以有限元素法建立模型及完成實驗與模型驗證，且將驗證的模型進行更深入的探討。
實驗方面主要分為三部分，第一部分為量測ILB製程時元件的溫度，第二部分為不同壓合力與下沉量和灌膠間隙三者之間的關係，第三部分為凸塊與引腳的偏移量與不同壓合力和下沉量和三者之間的關係，上述各項實驗數據可用於驗證有限元素模型的正確性。數值分析方面則先建立單引腳模型以探討內引腳接合過程的溫度傳遞現象，之後探討壓合力量、下沉量、灌膠間隙三者間之最佳化製程，進而探討引腳與凸塊之間偏移對結構的影響。本文之研究成果將有助於COF-ILB製程產品的開發，並且提供相關的ILB設計參考。

關鍵字

有限元素分析FEM ； ILB引腳接合 ； 覆晶軟板COF

並列摘要

Pressing temperature, pressing time, bump size, lead size, tin layer composition on lead and bonding force are some process parameter of Flip chip-on-film (FCOF) technique in the manufacturing process of Inner Lead Bonding. These parameters are affect the yielding rate and reliability of the product. In general, low yielding rate and low reliability of the process is caused by thermal deformation and the existing of stress / strain behavior, and they will leads different failure modes. Therefore the main purpose of this study is to optimize the manufacturing parameter design, and deformation of the interconnection and the occurrence of heat transfer in bonding process were taken into consideration. In addition, Finite Element Method (FEM) simulation model is developed for the verification of experimental results, and the model is used in further investigation.
The experiment is categorized into three parts. The first part is the temperature measurement of the components in ILB process, and the second part is to measure sinking value and edge gap for different bonding force, the last part is to discuss the offset and several bonding force leading to different sinking value. Part of the results was used to verify of the FEM simulation model. For numerical analysis, the single lead model was built to simulate the heat transfer during bonding process. Then use the simulation model to search the optimization design among bonding force, sinking value and edge gap. The influence of related offset between bump and lead to COF structure also discussed. The results could improve develop of COF-ILB products and provide relevant parameters for ILB design.

並列關鍵字

finite element method ； inner lead bonding ； flip chip on film

參考文獻

[1] Y. Yang, R. Labie, F. Ling, C. Zhao, A. Radisic, J. Van Olmen, Y. Travaly, B. Verlinden, and I. De Wolf, “Processing Assessment and Adhesion Evaluation of Copper Through-Silicon Vias （TSVs） for Three-Dimensional Stacked-Integrated Circuit （3D-SIC） Architectures,” Microelectronics Reliability, vol. 50, no. 9-11, pp. 1636-1640, 2010.

[2] G. S. Shen, “LCD Driver IC Assembly Technologies and Status,” in Int. Symp. Electronic Materials packaging, pp. 313-316, 2002.

[3] C. I. Chen, C. Y. Ni, C. M. Chang, S. C Wu, and D. S. Liu, “Bondability Study of Chip-on-Film (COF) Inner Lead Bonding (ILB) Using Conventional Gang Bonder,” IEEE Trans. Electron. Packag. Manuf., vol. 31, no. 4, 2008.

[4] C. Jang, S. Han, H. Kim, and S. Kang, “A Numerical Failure Analysis on Lead Breakage Issue of Ultra Fine Pitch Flip Chip-on-Flex and Tape Carrier Packages During Chip/Film Assembly Process,” Microelectronics Reliability, vol. 46, pp. 487-495, 2006.

[5] C. Jang, S. Han, J. Ryu, S. Cho, and H. Kim, “Issues in Assembly Process of Next-Generation Fine-Pitch Chip-on-Flex Packages for LCD Applications,” IEEE Transactions on Advanced Packaging, vol. 1, no. 30, pp. 2-10, 2007.