應用矽副載具於高功率發光二極體覆晶封裝技術之研究

Study of flip chip packaging technique on high power LEDs by adopting silicon submount

莊顏聞(Yan-Wun Jhuang)

指導教授 ： 陳文瑞

國立虎尾科技大學/電機資訊學院/光電與材料科技研究所/碩士(2010年)

摘要

本實驗主要藉由微機電技術(Micro Electro Mechanical Systems, MEMS) 製作出LED 微封裝結構，並以覆晶(Flip Chip) 封裝方式將其元件微小化及模組化，並搭配矽(Silicon) 之純熟製程技術將LED 封裝電路圖形製作於矽基板上，封裝電路製作完成後，藉由電鍍製程將電路電極增厚，降低電阻值提高導電率與導熱能力。在未來可望待此封裝技術成熟後預計採用晶圓級技術封裝(Wafer Level Packaging) 可大量模組化製作以降低製作成本。
實驗中我們分別研究不同電極厚度對於導電率與散熱性之差異，發現在電鍍銅2μm 和5μm 之間電阻值有明顯的下降約為0.14Ω ，並且表面溫度會隨著電極厚度增加而下降(68.3oC、63.8oC) ，但由於銅易氧化於是鍍上一層金膜以防止氧化，發現有鍍金層與未鍍金層在氧化測試後其電阻值有明顯的差異約為0.016Ω 。並探討覆晶封裝底部填四種不同膠體(鑽石膏、碳膠、矽膠、環氧樹脂)觀察對於LED 散熱之幫助性並與無底部填膠作比較，實驗結果發現底部填膠後表面溫度比較低，其中以鑽石膏下降幅度最大約為12.51%，其次為Carbon (9.02%) ，Silicone (7.13%) ，Epoxy (5.38%)。

關鍵字

發光二極體 ； 覆晶封裝 ； 底部填膠

並列摘要

This thesis is to by the MEMS (Micro Electro Mechanical System) produced the LED micro-package structure, and used for Flip Chip technique, components of small size and modulization. Fabricate the LED packaged circuit patterns in Silicon substrate with silicon skilled process technique. After packaged circuit, we used electrode plating process to thicken the electrode reducing resistance, and raising conductivity and heat dissipation. It expects to use Wafer Level Packaging to produce numerous modules for reducing the manufacturing cost in the future after this packaged technique skilled.
In this study, we experimented with different thick electrode and discovered the difference between conductivity and heat dissipation. According to the Cu electroplating experiments, the resistance decreased obviously about 0.14Ω at 2μm and 5μm. The surface temperature will decrease with the increase of electrode thickness (68.3oC, 63.8oC, respectively). However the Au film was electroplated to prevent oxidation on Cu surface since Cu was easily oxidized. The result showed the difference between with and without Au of resistance was about 0.016Ω after the oxidation tests.
Moreover, we used four types different under filler materials (Diamond, Carbon, Silicone, and Epoxy) to observe LED heat dissipation compared with the without filler. It showed that the surface temperatures became lower after filler. Especially filler with Diamond, it declined about 12.51%. Subsequences were Carbon (9.02%), Silicone (7.13%), and Epoxy (5.38%).

並列關鍵字

LEDs ； Flip Chip ； under fill

參考文獻

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