雷射加工異質材料之性質研究

The Investigation on the Behaviors of the Heterogeneous Material in Laser Process

林文斐(Wen-Fei Lin)

指導教授 ： 洪博彥

共同指導教授 ： 徐祥禎 ； 吳士傑(Shih-Jeh Wu)

義守大學/理工學院/材料科學與工程學系/博士(2021年)

摘要

本研究對雷射加工劃區屏蔽技術（compartment shielding），進行了一系列實驗規劃；目的在探討雷射加工異質材料時，不同的加工條件對材料性質、加工產生溫度的影響，並提供材料面對雷射加工時的基礎知識。
研究目標是成功導入雷射用於半導體封裝製程，穩定產品量產品質。令人關心的議題有如材料本身的品質、環境輔助氣體的影響、不同異質材料對雷射畫線的反應、加工過程產生之溫度等等。
實驗規劃分為兩個前置實驗與最終實驗，前置實驗是為了將最終實驗排除不必要的影響因素。第一組前置實驗是材料穩定性的實驗，不同填充物尺寸的異質材料12μm和48μm，經雷射加工後的穩定性。第二組前置實驗是雷射加工異質材料時，以氮氣、氧氣、空氣等三種輔助氣體噴於加工處，觀察輔助氣體對加工結果的影響。最終的主要實驗是將熱電偶埋於異質材料中，紀錄雷射畫線過程產生的溫度。確定加工過程的熱不會對半導體產生負面影響。
結果是封裝的填充物尺寸12μm比48μm穩定；輔助氣體對雷射加工的效果影響太小，需佐以清洗；雷射加工最高的測得溫度是100.94℃，低於常規半導體的燒機測試溫度（250℃），得到雷射加工不會對距離加工處200μm的電子元件造成破壞的結論。

關鍵字

劃區屏蔽 ； 雷射燒蝕 ； 紫外光雷射 ； 微米製程 ； 環氧樹酯封裝 ； 雷射輔助氣體 ； 異質材料 ； 熱設計

並列摘要

This thesis experiments for the compartment shielding machined by laser are conducted. The purpose of this research is to investigate how the process parameters affects the outcomes of irradiated i.e., material properties, temperature rise and the induced impact during laser machining process on heterogeneous materials.
These objects of research are by using laser as a main tool in microelectronic packaging process under stabilized the quality of mass production. Key issues concerned are the properties of material, effect of aided gas, the behaviors of heterogeneous materials during laser process, and how much temperature created. Hopefully the findings from this research can be helpful to field and process engineers as fundamental knowledge base.
Experiments are planned as two-part pre-studies and the final experiment. The two-part pre-studies are set to preclude the unnecessary factors from the final experiment. First set of experiments is on the stability of materials of different filler sizes, i.e., 12 and 48μm after laser processing. Second, during laser scribing on the heterogeneous material, one of three kinds of gases, i.e., nitrogen, oxygen, and air were used to assist the ablation process and the results were observed and recorded for optimal settings, e.g., flow rate. Finally, the temperature during laser scribing the heterogeneous material at certain locations were measured by thermal couples embedded in the target work pieces to ensure there is no side effects from heat on the semi-conductor components i.e., Heat Affect Zone.
Results show that filler size 12μm is more stable than that 48μm. Assisting gas is not enough for cleaning material, and offline clean by chemical solution or dry ice is necessary. The highest local temperature at 100.9℃ was measured during laser process which is lower than the burn-in test temperature, 250℃, and it shows that laser process designed won’t damage the electrical components away from the scribing area 200μm.

並列關鍵字

Compartment shielding ； Laser ablation ； UV laser ； Micromanufacturing ； Epoxy molding compound (EMC) ； Gas-aided laser ； Heterogeneous material ； Thermal design

參考文獻

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