打線製程是最主要用來連結矽晶圓與基板的一種方式。金線是傳統且最受歡迎的線材，但金線的價格太高，為了節省製程成本，銅線開始被廣泛的研究，因為其價格相對低廉，且導電性、導熱性等條件皆優於金線;因為銅線的諸多特性，使得銅線製程的趨勢備受注目。但在實際運用層面上受到銅的本身活性高易氧化的問題，限制了銅線的發展與使用。
為了克服氧化的問題，近年來提出了使用鈀鍍層在銅線上，在銅線表面鍍上一層抗氧化保護層以達到阻隔氧化目的。但是鍍鈀銅線本身硬度較高，在製程中需提供較高能量，而容易造成晶片或鋁墊受損的缺點。所以又進一步發展出鍍金鈀銅線與合金鈀銅線，鍍金鈀銅線其有更好的韌性，而合金鈀銅線卻有最少的製造程序成本便宜的優點。
本論文擬對新興的打線材料合金鈀銅線與鍍金鈀銅線進行材料介金屬成長之研究。觀察銅鋁介金屬化合物，在以不同接合能量參數接合後，經過高加速溫度濕度未飽和蒸氣應力測試（High Accelerated Temperature and Humidity Stress Test, HAST）與高溫儲存測試（High Temperature Storage Test, HTST）下，隨著時間介金屬化合物的變化與成長。以FE-SEM觀察介金屬組織的演化，同時以背向散射電子(Electron Backscatter Diffraction Analysis, EBSD)分析技術鑑定介金屬化合物的晶體結構，另一方面利用電子顯微鏡上附加的能譜分析儀(Energy Dispersive Spectrometer, EDX)與歐傑電子能譜(Auger electron spectroscopy, AES)分析銅球與界面鈀元素分佈的情形。並以SEM-BEI影像結合影像分析軟體計算介金屬的總厚度。最後推論兩線材的介金屬演化與破裂膜型，以探討其銅鋁間介金屬化合物成長及相變化情形。
研究打線剖面接合界面結果顯示，鍍鈀金鍍層線材的介金屬化合物成長速度較鈀合金線材快速。因打線製程的燒球過程中，形成FAB所造成的流動，並不會使得鈀金鍍層線材的鈀原子均勻分佈在接合界面。但是以參雜方式固溶鈀原子在銅線內部的合金線材，因均勻的分佈在銅線內，形成了一種延緩銅原子擴散進入界面的效果，其在可靠度測試下表現較佳。

Wire bonding is a key technique to provide electrical interconnections between integrated circuit(IC) chips and lead frames in microelectronics. Gold is the most popular interconnection material in wire bonding, due to cost savings and better electrical and mechanical properties, copper wires has been studied worldwide. There are many potential for use of copper in these applications, However, Cu bonding wire they have oxidation problems severely limited in their use.
In recent years, Pd-coated type copper wire has been developed, Pd-coating layer prevents oxidation of the wire surface, but Pd-coated copper ball were increase its hardness at ball surface may in turn exacerbate damage to bond pads or wafer, which is already a problem in coated-copper wire bonding. So Pd-alloy and Pd-Au copper wire has been developed, they have better toughness, but Pd-alloy copper wire has more fewer manufacturing process steps compared to Pd-Au coated copper wire, so they have cost down for Electronic Packaging.
In this study focused on Cu-Al intermetallic compounds (IMCs) analysis for Pd-alloy and Pd-Au-coated copper wire. From cross-sections images of the wire bonds interface IMCs evolution by SEM after HTST and HAST reliability aging tests, the microstructures of intermetallic compounds were observed by field emission SEM. The Pd element distribution at the ball bond and interface were analyzed by SEM-EDS and AES-linescan. The IMCs structure was identified by the electron backscatter diffraction (EBSD). Combine the SEM-BEI images and EDS were analyzed through the image analysis software to determine the total thickness of IMCs.
For different types of copper wire, IMCs growth rate of Pd/Au-coated copper wire is faster than Pd-alloy copper wire. Because in the bonding process of EFO (electronic flame-off ), the copper flow did not make the Pd atoms distribution in the bonding interface for Pd/Au-coated copper wire. However, Pd-alloy copper wire has a uniform Pd elements distribution, that delayed copper atoms diffusing into interface, so Pd-alloy copper wire provided a better reliability performance.

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