因應科技迅速變遷，半導體的產業如今在全球各地蓬勃發展。印刷電路板是用來固定IC和其他電子元件的重要基板，讓不同功能的IC和電子元件藉由一條條的導線連接起來，藉此達到處理電子信號的功能。同時底部的銅基地或是鎳基地的基板容易氧化的影響。大氣電漿技術近年來由於不須使用真空腔體還有可以進行連續性的製程，在產業上有使用的趨勢，同時通入不同的工作氣體能對表面進行不同的處理。
本研究利用常壓電漿噴射束，對裸銅板的表面氧化銅進行還原，評估其還原效應的效果以及是否能有效增加銲接接合的強度。研究先使用熱重分析儀分析氧化銅的裂解溫度，比較和大氣電漿不同工作距離(3mm、4mm、5mm)。工作氣體氬氣混入不同氫氣比例(1%、2%)的變化下，還原溫度的差異。並利用光學發射光譜儀對於大氣電漿的物種進行探討。
實驗結果顯示，裸銅板在常壓電漿噴射束的處理下，水接觸角都能得到有效的提升，二碘甲烷的角度沒有太大差異，表示物理結構並沒有太大的改變。從光學發射光譜儀中的電漿物種分析可以得知電漿裡面含有氫有利於還原的物種Hα。擴散角的量測表示了大氣電漿對於表面的銲接接合力能有效地提升。四點探針量測薄膜電阻的表面受到電漿處理後，表面電阻率下降，氧化物成功還原。使用X光光電子能譜儀對表面進行分析，XPS圖譜中可以看到Cu2p裡面的的銅金屬下降，氧化銅成功利用大氣電漿還原，Cu LMM的圖譜可以了解Cu2O和Cu在還原後同時存在。銲接的接合強度得到提升，並且在高溫爐的烘烤後仍保持一定的強度，斷裂面呈現延性的情況。使用熱燈絲式電子顯微鏡觀察介金屬化合物在裸銅板和無鉛銲料錫球之間的反應情況。進一步探討不同幾何形狀的噴頭對於表面處理效果，還有無助銲劑製程的可行性實驗。

In this generation, technology has been changing all of our life. The industry of semiconductor widely develop around the world. Printed circuit board is used to fix the ICs and electronic components. Connecting the components by wire is the method to process electronic signals. Cu-based and Ni-based substrates are easily oxidized in our environment. No needed of vacuum cavity and proceeded consistent treatment are the major advantages of atmospheric pressure plasma (APP). By injecting different working gas, the substrate can do different surface treatment and the equipment of APP is a new trend in industry.
In this study, we are using atmospheric pressure plasma jet (APPJ) to remove the oxidized layer on bare Cu. Evaluating the effect of reduction and the bonding between lead free solder ball and substrate are discussed. In the beginning of this experiment, we used thermos gravimetric analyzer to observe the reduction temperature of CuO. The above result is compared the plasma temperature of working distance 3, 4, and 5 mm. By adjusting the different concentration of H2 of 1% and 2% and using optical emission spectroscopy (OES), evaluating the different reduction temperature and detecting the species of APP are discussed.
The results show the surface becomes hydrophilic. On the other hand, CH2l2 contact angle remains similar contact angle after treatment. This results show the physic structure does not change by APPJ. From OES inspection, H radicals are tested and they are benefit to remove the oxidation. Spreading ratio shows the improvement of bonding between solder ball and bare Cu. Conductivity is tested by four-point probe shows lower number after treatment, which means the oxidize layer is removed by plasma. X-ray photoelectron spectroscopy shows Cu2p of metal oxidize becomes lower. Cu LMM spectrum shows Cu2O and Cu are coexisting. Shear test proves to increase the bonding of soldering. Even after high temperature storage, the shear remain certain strength. The fracture surface performs ductility. Intermetallic compound reaction between bare Cu and solder ball is observed by scanning electron microscope. Furthermore, different geometric shape of plasma head and the feasibility of flux free solder are explored.

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