Gan, Zhong Li (2018) Simulation Of Underfill Encapsulation Of Electrionic Packaging Using The Lattice-Boltzmann Method. Masters thesis, Universiti Sains Malaysia.
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Abstract
Kebanyak kajian berasaskan kaedah isipadu terhingga (FVM) telah dilaksanakan untuk mengoptimumkan dan memperbaiki proses pengkapsulan isian bawah. Namun, terdapat kajian yang terhad telah dilaksanakan dengan kaedah kekisi-Boltzmann (LBM) untuk aplikasi yang berkaitan dengan pengkapsulan isian bawah. Dalam kajian ini, LBM akan digunakan untuk mensimulasikan proses pengkapsulan untuk sendi pateri yang berlainan bentuk, penyusuan sendi pateri dan cara dispens. Sesetengah keputusan simulasi yang diperolehi dengan LBM akan dibandingkan dengan keputusan yang diperolehi daripada eksperimen pengimejan velocimetri partikel (PIV). Keputusan yang diperolehi daripada simulasi LBM dan eksperimen PIV adalah lebih kurang seiras. Dari segi penyusunan sendi pateri, adalah didapati bahawa penyusunan jajaran keliling memberikan masa pengisian yang paling singkat berbanding dengan penyusuan jajaran kosong tengah dan penuh. Bagi kaedah suntikan berbeza, adalah didapati bahawa kaedah penyutikan jenis U memberikan pengurangan masa pengisian sebanyak 67% berbanding dengan penyuntikan jenis I. Namun, ruang kosong yang besar dibentuk dengan kaedah suntikan jenis U. Suntikan jenis L pula menunjukkan pengurangan masa isian sebanyak 45% tanpa formasi ruang kosong makro. Di samping itu, kesan bentuk sendi pateri yang berbeza juga dikaji. Jajaran sendi pateri dengan sendi berbentuk jam pasir berjaya mengurangkan masa pengisian sebanyak 10% sambil menghasilkan ruang kosong yang lebih kecil. Sendi pateri berbentuk silinder tidak menunjukkan sebarang penambahbaikan yang ketara kepada masa pengisian kalau dibandingkan dengan pengisian bawah dengan sendi pateri xx konvensional yang berbentuk sfera terpenggal. Isian bawah tekanan dapat mengurangkan masa pengisian sehingga 99% berbanding dengan isian bawah konvensional. Tekanan maksimum dalam domain aliran adalah lebih kurang 2.5 hingga 3 kali lebih tinggi daripada tekanan masuk semasa isian bawah yang disebabkan oleh pembinaan tekanan. _______________________________________________________________________________________________________ Many finite volume method (FVM) based studies had been conducted by researchers to optimize and improve the underfill encapsulation process. However, there are limited studies conducted using lattice-Boltzmann method (LBM) for underfill encapsulation process. In this study, LBM will be used to simulate the encapsulation process of different solder joint shapes, different solder joint arrangements and injection methods. Some of the simulation results obtained using LBM will then be compared with the results obtained from experiment using particle image velocimetry (PIV) method. High conformity were obtained from both LBM and PIV results. In terms of the solder ball arrangements, perimeter arrangement was found to give the shortest filling time compared to middle empty and full arrangements. As for different injection methods, it was found that U-type injection gives a 67% reduction of filling time compared to I-type injection. However, a huge void is formed with U-type injection. Meanwhile, L-type injection shows a 45% reduction of filling time with no macro void formed. Furthermore, the effect of different solder joint shapes are also studied. Solder joint array with hourglass shape solder joints managed to reduce the underfill filling time by around 10% while yielding a smaller void. Cylindrical shape joints did not show any significant improvement on the filling time compared to that with truncated sphere shape joints. Pressurised underfill was found to reduce filling time by up to 99% compared to conventional underfill. The maximum pressure within the flow domain was found to be approximately 2.5 to 3 times higher than the inlet pressure during pressurised underfill due to pressure build-up.
| Item Type: | Thesis (Masters) |
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| Additional Information: | Full text is available at http://irplus.eng.usm.my:8080/ir_plus/institutionalPublicationPublicView.action?institutionalItemId=4697 |
| Subjects: | T Technology T Technology > TJ Mechanical engineering and machinery > TJ1-1570 Mechanical engineering and machinery |
| Divisions: | Kampus Kejuruteraan (Engineering Campus) > Pusat Pengajian Kejuruteraan Mekanikal (School of Mechanical Engineering) > Thesis |
| Depositing User: | Mr Mohd Jasnizam Mohd Salleh |
| Date Deposited: | 13 Jun 2019 08:37 |
| Last Modified: | 13 Jun 2019 08:37 |
| URI: | http://eprints.usm.my/id/eprint/44590 |
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