探討扇出型面板級封裝結構離型取下之機械行為

Investigating Mechanical Behaviors of Fan-Out Panel Level Packaging Structures during De-bonding

林枋萭(Fang-Yu Ling)

指導教授 ： 蔡佳霖

國立交通大學/工學院/機械工程系所/碩士(2018年)

摘要

本研究主要利用有限元素法，模擬扇出型面板級封裝(Fan-Out Panel Level Packaging, FOPLP)於製程中之機械行為，研究中探討製程包含封裝結構熱循環(thermal cycling process)製程與離型取下(de-bonding process)，藉由對FOPLP封裝結構進行分析與探討，進而避免結構在製程中產生脫層而損壞或失效。
　　研究內容針對FOPLP封裝結構建立二維模型，並探討其機械式離型取下(Mechanical loading induced de-bonding)過程之行為，利用主模型與子模型 (Global Model Method and Local Model Method)模擬技術，來探討FOPLP封裝結構在製程中所受之應力分佈，藉由調整結構之幾何與材料參數，協助FOPLP之製程開發，並討論製程熱效應造成之內應力對離型取下之影響。
　　此外，進一步將熱循環製程考慮於結構中，以探討熱翹曲與離型界面脫層行為，因結構熱翹曲為三維問題，透過雙材料破壞力學理論，計算脫層時微小缺陷之總應變能釋放率。利用熱循環製程後之雷射取下(Laser assistance de-bonding)模擬技術，修正結構中環氧模壓樹脂之模型，使封裝結構之製程模擬更連貫且完整。
　　最後將模擬技術應用於TFT-FOPLP面板級封裝結構中，其結構為FOPLP封裝結構之應用延伸，藉由將薄膜電晶體(Thin-Film Transistor, TFT)製於晶片外，藉由主模型與子模型模擬技術，建立多階子模型，討論細微尺寸結構於熱循環製程中所造成之應力與應變，並用於分析製程中導電通道之電性行為。

關鍵字

扇出型面板級封裝 ； 離型取下 ； 熱翹曲 ； 主模型與子模型 ； 應變能釋放率 ； 脫層行為 ； 有限元素法

並列摘要

This research aims to investigate the mechanical behaviors of a Fan-Out Panel Level Packaging (FOPLP) display during the fabrication process using finite element analysis. The fabrication process includes the thermal cycling process and the de-bonding process of FOPLP display. By understanding the stress and strain distribution with FOPLP display, the degree of damage or failure for the FOPLP display during fabrication process can be reduced.
In order to understand the mechanical de-bonding process, a simplified FOPLP two-dimensional finite element model was established. By adopting the technique of global model and local model simulation, the stress states within FOPLP display can be calculated. In addition, the thermal stress generated was also taken into account in the simulation. By adjusting the geometry and material properties, the stress state with the FOPLP can be reduced, which is helpful in the development of FOPLP.
In addition, the warpage deduced during the thermal cycling process together with the delamination was investigated in the study. Since the thermal warpage is a three-dimensional problem, a three-dimensional finite element model was introduced and the total energy release rate of the defect at the onset of delamination was calculated by using bi-material fracture mechanics. Moreover, the consideration of laser assistance de-bonding technology after the thermal cycle process and the modification of mechanical model of Epoxy Molding Compound (EMC) make the simulation results more complete.
The simulation technique established in previous section was extended to investigate the mechanical behaviors of FOPLP with Thin-Film Transistor (TFT) embedded underneath the Die. The TFT-FOPLP structure was examined through global-local simulation, and the stress and strain states of TFT after thermal cycling were calculated. The information will be employed to understand the electrical behavior of channel during the fabrication process.

並列關鍵字

Fan-Out Panel Level Packaging, FOPLP ； De-bonding ； thermal warpage ； Global Model Method and Local Model Method ； total energy release rate ； delamination ； finite element

參考文獻

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