鋁鍺銦錫暫態液相鍵結接合面之結構分析

Structural analysis of AlGeInSn bonded joints prepared by transient liquid phase bonding

林彥竹(Yen-Chu Lin)

指導教授 ： 陳文瑞

國立虎尾科技大學/電機資訊學院/電子工程系碩士班/碩士(2015年)

https://doi.org/10.6827/NFU.2015.00042

摘要

本研究以真空熱蒸鍍法製備鋁鍺銦錫薄膜金屬結構層於玻璃基板上，探討不同溫度之熱壓合與不同厚度之電鍍錫增厚層，透過暫態液相鍵結技術做鍵合，並使用週期熱循環的方式加以探討金屬接合面材料之特性，以剪應力強度測試、SEM、EDS及XRD分析研究經由熱壓合後樣品薄膜對鋁鍺/錫介面以及鋁鍺/銦錫界面應力之影響及其表面形貌、微觀結構、成分比例與晶體相位之分析。據剪應力強度表統計，在280oC中，電鍍錫增厚層1~3μm，當熱循環增加至三個週期，平均剪應力強度達到了> 12 kg/cm2，隨降溫至較低的260oC及240oC，熱循環週期次數的增加，剪應力強度有了相對上升增強的趨勢，於260oC中，電鍍錫增厚層至2~3μm，熱循環週期次數增加至四個週期以上，及電鍍錫增厚層1μm，熱循環週期次數增加到五個週期，剪應力強度都到達了 >12 kg/cm2。其中經由SEM與EDS斷裂面分析，於高溫度280oC當電鍍錫增厚層至3μm，施加三個週期熱循環，以及於低溫度的240oC當電鍍錫增厚層至1μm，施加五個週期熱循環，強度甚至將薄膜撕扯掉，剩下玻璃基板，由此較厚的錫於高溫中，除了能夠改善接觸面間隙的誤差並較多錫算擴散使剪應力強度上升，反觀於低溫中只剩下銦錫的擴散，較薄的錫使得整體金屬結構層擴散完整。而實驗結果經XRD分析得知，不同溫度熱壓合與不同電鍍錫增厚層與施加不同次數熱循環週期，各種不同情況下，隨著熱循環週期的次數增加，存在著In0.05Sn0.95 α相(200)面、(220)面、(211)面，In0.1818Sn0.8182 β相(100)面、(101)面，In0.75Sn0.25 γ相(220)面，這幾個合金相的存在，並且相對得剪應力強度的上升與增強；In0.05Sn0.95 α相會逐漸得出現且增強，而In0.1818Sn0.8182 β相與In0.75Sn0.25 γ相則逐漸得削弱甚至消失，相轉成α相。

關鍵字

鋁鍺銦錫薄膜 ； 暫態液相鍵合

並列摘要

In this study, Aluminum-Germanium and Indium-Tin metal structural films were prepared by vacuum thermal evaporation on the glass substrate. In order to explore the effect of different temperatures of hot tin plating layers with different thicknesses, the transient liquid bonding technology and the thermal cycles were performed, the thermal cycling characteristics of the metal joints were relative to the shear strength. After the thermo-compression bounding, the SEM, EDS and XRD analysis of the samples were carried out and by inspection the AlGe/Sn interfaces and AlGe/InSn one. Then we observed the impact of stress, surface morphology, microstructure, and composition ratios of the crystal phases.
According to the shear stress statistics, at 280 oC the average shear strength was found to be larger than 12 kg/cm2 while the heat cycles were applied from one to three cycles. When the bounding temperature was reduced to 260 oC or even as low as 240 oC, it was found that the shear stress intensities rise with increasing the number of thermal cycles. At the 2~3μm thickness of tin plating, the number of thermal cycles was increased to four or more while the shear stress has reached the value of 12 kg/cm2 which is the limit of highest value in our shear tester. However, for the 1μm thickness of tin plating, the number of thermal cycles needs five thermal cycles to reach the maximum stress of 12 kg/cm2.
The fracture surface of samples was examined by SEM and EDS analysis. One sample with a 3 μm-thick Tin plated layer was applied three thermal cycles at high temperature of 280 oC. Also, the other one with 1μm-thick Tin plated layer was applied five thermal cycles at low temperature of 240 oC. Both these two samples have very strong bounding strength and even are torn off the substrate.
From the XRD analysis, under different bounding temperatures, different thickness of tin plated layer and thermal cycles, the samples with the increase in the number of heat cycles are the In0.05Sn0.95 α phase(200), (220), (211), In0.1818Sn0.8182 β phase (100), (101), and In0.75Sn0.25 γ phase (220). These co-crystal phases and the relatives were enhanced and got stronger when their shear stress was increased. Here the In0.05Sn0.95 α phase was gradually obvious and enhanced, The In0.1818Sn0.8182 β phase and the In0.75Sn0.25 γ phase were gradually weakened or even disappeared. It is attributed that the β and γ phase might have a transition into α phase.

並列關鍵字

Aluminum-germanium indium-tin film ； Transient liquid phase bonding

參考文獻

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