球格陣列封裝（Ball Grid Array Packaging, BGA）製程會經歷兩個熱處理，迴銲（reflow）和時效（aging），這兩段熱處理會影響錫球與UBM（Under Bump Metallization）所產生的界面變化。Sn-Zn系為無鉛錫球非常有希望取代傳統SnPb錫球的候選者；而經由界面反應產生的IMC（intermetallic compound）為影響錫球的機械強度最重要的因素，在整個實驗過程中，Sn-9Zn和Sn-8Zn-3Bi為共晶成份，在SEM觀察下，錫球為共晶組織，Zn扮演界面反應的供應者，使UBM中的Au在熔進進錫球內，形成AuZn3（γ相），並在後續時效下，形成AuZn4（γ3相）和其周圍的析出Zn相；另外底部的Ni層，形成Ni5Zn21，在時效下持續成長。在Sn-Zn-Al錫球，0.01％的Al讓界面反應產生很大的變化，在底部形成Au-Al-Zn layer，等同於diffusion layer，阻礙了Ni5Zn21的產生，另外在Au-Zn IMC旁邊聚集形成顆粒狀的Au-Al IMC。
在錫球通電流實驗中，會引起焦耳熱效應和電遷移效應，從對照Sn-Zn錫球在175℃時效產生的界面反應，Ni元素的擴散引起帶狀AuZn4（γ3相）的分解，形成（Au, Ni）Zn4，然而錫球的正負極在SEM觀察下並沒有發現孔洞，以及正負極的Ni5Zn21並沒有厚度上的差異，也就是電遷移的最明顯的質量傳送的極化效應，沒有觀察到；反而是高溫下才能產生的Au-Ni-Zn三者的相變化，並經由熱電偶直接量測通電流後提高的溫度，都再次證實焦耳熱效應的存在。

The interfacial reactions of Sn-Zn and Sn-Zn-Al solder balls with Au/Ni surface finish under aging at 150℃ were investigated. With microstructure evolution, quantitative analysis, elemental distribution by X-ray color mapping from an electron probe microanalyzer (EPMA), the reaction procedure of phase transformation was proposed. During the reflow, Au dissolved into the solder balls and reacted with Zn to form γ-Au3Zn7. As aging time increased, γ-Au3Zn7 transformed to γ3-AuZn4. Finally, Zn precipitated near the Au-Zn intermetallic compound. On the other hand, Zn reacted with the Ni layer and formed Ni5Zn21. But the Al-Au-Zn IMC formed at the interface of Sn-Zn-Al solder balls, the reaction of Ni with Zn was inhibited. Even though the aging time increased to 50 days, no Ni5Zn21 was observed.
The Joule effect was more apparent than the electromigration in the biased solder balls. First of all, the new phase (Au, Ni)Zn4 was proposed in the biased condition and in 175℃aging. Secondly, the thickness of the Ni5Zn21 IMC were the same between the anode and the cathode. Finally, We directly measure the temperature of the biased solder balls which was up to 173℃.

目錄
目錄 Ⅱ
圖目錄 Ⅳ
壹、前言 1
貳、文獻回顧 2
2-1電子構裝的發展趨勢 2
2-2界面冶金反應 2
2-2-1傳統SnPb錫球與Au/Ni墊層的反應 3
2-2-2 Sn-Ag-X系統銲錫與Au/Ni墊層的反應 4
2-2-3 Sn-Zn-X系統銲錫與Au/Ni墊層的反應 5
2-2-4電遷移效應對界面反應的影響 6
2-3加速環境測試(Accelerated Environmental Stress Tests) 7
叁、實驗方法 11
3-1 實驗目的 11
3-2 實驗條件 11
3-2-1高溫儲存試驗 12
3-2-2通電流+高溫150℃儲存試驗 12
3-3試片成份 13
3-4試片製作 13
3-5試片分析 13
肆、實驗結果 15
4-1高溫時效對Sn-9Zn錫球微結構的影響 15
4-2高溫時效對Sn-7.23Zn-0.01Al錫球微結構的影響 16
4-3高溫時效對Sn-8Zn-3Bi錫球微結構的影響 18
4-4通電和高溫時效對Sn-9Zn錫球微結構的影響 20
4-5 175℃時效對Sn-9Zn錫球微結構的影響 23
伍、討論 25
5-1 Sn-9Zn錫球的界面反應 25
5-2 Sn-Zn-Al錫球的界面反應 26
5-3 Sn-8Zn-3Bi錫球的界面反應 27
5-4通電和高溫時效對Sn-9Zn錫球的界面反應 28
5-5 175℃和150℃高溫時效對Sn-9Zn錫球的界面反應比較 29
陸、結論 32
6-1 Sn-9Zn錫球與Au/Ni/Cu層的界面反應 32
6-2 Sn-Zn-Al錫球與Au/Ni/Cu層的界面反應 32
6-3 Sn-8Zn-3Bi錫球與Au/Ni/Cu層的界面反應 33
6-4 Sn-9Zn錫球通電流和150℃時效下的界面反應 33
6-5 Sn-9Zn錫球在175℃時效下界面反應 32
柒、參考文獻 35
捌、圖 39
玖、附錄 103

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