液相錫銀鉍銦無鉛銲料與銅基材反應之研究

本論文為研究錫銀鉍銦無鉛銲錫與銅基材之反應的研究，Bi與In的添加使84Sn3Ag3Bi10In與89Sn3Ag3Bi5In兩種銲錫的熔點分別降到203℃與212℃。實驗中形成的介金屬化合物為Cu6Sn5與Cu¬3Sn，實驗結果並未發現In取代Sn的情況；除了界面處外，銲料內部亦有Cu6Sn5的存在，與大量細微顆粒散佈於銲料中。實驗以自行混合的84Sn3Ag3Bi10In與89Sn3Ag3Bi5In兩種無鉛銲料與Cu基材進行液相-固相反應，模擬液態銲錫與Cu基材進行迴銲的介面反應情形；藉由影像軟體計算介金屬化合物的厚度，求出反應的化合物的成長速率常數k與時間對數n，比較n為1/2、1/3、1/4等數值，發現n值為1/3時最接近本實驗的結果，顯示化合物的成長為熟化控制機制；以Arrhenius equation算出84Sn3Ag3Bi10In與89Sn3Ag3Bi5In銲錫在液相下與銅生成Cu6Sn5介金屬化合物時所需要的視活化能，分別為48.3 kJ/mol與55.1 kJ/mol，與過去文獻結果比較，發現實驗使用的Sn-Ag-Bi-In系統銲料的平均視活化能低於文獻中使用的共晶錫鉛銲料的116 kJ/mol與錫銀銲料的54kJ/mol。實驗另外也觀察了散佈於銲錫中介金屬化合物的成分，藉由電子微探儀的偵測，得知此散佈於迴銲後之銲錫中的細小顆粒主要成分為Sn、Ag、In三種原子以不固定比例組成之具有大範圍固溶區之ζ相顆粒，為HCP結構。隨著反應時間的增加，Sn與In溶入顆粒中，銲料中出現兩相或是三相共存的顆粒。在界面處並未發現In原子溶入Cu6Sn5及Cu3Sn。

關鍵字

無鉛銲錫；界面反應；介金屬化合物

並列摘要

This thesis investigated the phenomenon of the reactions between Sn-Ag-Bi-In lead-free solders and Cu substrates. Two lead-free solders, 84Sn3Ag3Bi10In and 89Sn3Ag3Bi5In, were used to investigate the liquid-solid state reactions. The addition of indium and bismuth decreases the melting point of 84Sn3Ag3Bi10In and 89Sn3Ag3Bi5In to 203 and 212℃, respectively. Two layers of intermetallic compounds, Cu6Sn5 and Cu3Sn, formed between the solders and the substrates. The results revealed that In atoms did not dissolve in the intermetallic compounds to replace Sn atoms. Besides, some Cu6Sn5 spalled and many fine Sn-Ag-In particles dispersed in the solders. The growth rate constant and the growth exponent could be deduced from the calculation of the thickness of the intermetallic compounds. The fitted results revealed that the growth exponent n equals to 1/3 and suggested a ripening controlled process during reflow. The apparent activation energy could be calculated by Arrhenius equation and that of the growth of Cu6Sn5 and Cu3Sn was 48.3 kJ/mol and 55.1 kJ/mol, respectively. The composition of the intermetallic compounds that dispersed in the solders was analyzed by electron probe microanalysis. The results suggested that the fine particles mainly areζphase that were composed of Sn, Ag, and In atoms with large miscibility range. The ζ phase is the solid solution of ζ (Ag4Sn) and ζ (Ag3In), which both have the crystal structure of HCP. Sn and In dissolved more in the dispersed particles with increasing reflow time. No In signal could be detected in the intermetallic compounds at the interfaces during reflow.

並列關鍵字

lead-free solder ； interfacial reaction ； intermetallic compound

參考文獻

[6] William D. Callister, Jr., Materials Science and Engineering - An Introduction, United States of America: John Wiley & Sons, 2003, pp. 92.

[7] D. R. Frear, and P. T. Vianco, “Morphology and Growth Kinetics of Intermetallic Compounds in Solid-State Interfacial Reaction of Electroless Ni-P with Sn-Based Lead-Free Solders,” Metall. Mater. Trans. A, vol. 25A, no. 7, 1994, pp.1509-23.

[8] A. Rahn, The Basics of Soldering, New York: John Wiley & Sons, 1993.

[9] K. Zeng, R. Stierman, T. C. Chiu, D. Edwards, K. Ano, and K. N. Tu,” Kirkendall void formation in eutectic SnPb solder joints on bare Cu and its effect on joint reliability,” J. Appl. Phys., vol. 97, 2005, pp.024508 1-024508 8.

[10] S. W. Chen, C. H. Wang, S. K. Lin, C. N. Chiu, and C. C. Chen, ”Phase transformation and microstructural evolution in solder joints,” JOM, vol. 59, 2007, pp.39-43.

國際替代計量

液相錫銀鉍銦無鉛銲料與銅基材反應之研究

全文下載

主題瀏覽