摘要
基于固体相变理论,研究Au丝、Al丝超声楔-楔键合接头的温度长期可靠性。200℃下,存储时间<48 h时,Au/Al接头界面并未发生明显变化;随着接头存储时间增加,界面金属间化合物(IMC)开始由焊盘向引线方向生长(垂直生长);240 h时,Al焊盘完全被消耗,接头连接界面部位生成Au5Al2,周边为Au2Al;继续增加存储时间,IMC向接头水平方向生长(水平生长),Au5Al2向更稳定的Au2Al转变,IMC与引线之间形成严重的Kirkendall孔洞。Al/Au系统相对稳定得多,界面IMC生长缓慢,然而,界面化合物AuAl2导致接头裂纹,而引线内部出现严重的空洞。对比并分析了两种楔焊系统界面演变特点和产生机制。
Based on the metallurgical theories and thermal aging test methods, the long -term thermal reliabilities of gold and aluminum wedge bonding on aluminum and Au/Ni/Cu pads respectively were investigated. At 200 ℃, the Au/A1 bond interfaces evolved little when the storage time was less than 48 h;With the aging time increasing, the interfacial intermetallic compounds （IMC） grew up from the pad （vertical growth） ;the primary compounds were AusAl2 near the bond toe and heel,and Au2Al at the periphery. Then, the thickness of IMC was unchanged, and extended horizontally （ lateral growth） , Aus AlE transformed into more stable AuEAl phase ,furthermore, cracks ran through interface between the wire and IMC because of severe Kirkendall voids. However, Al/Au bond was more stable, and the IMC grew slowly. The purple plague AuAl2 resulted in interfacial cracks. Moreover, the bond wire was filled with cavities.
出处
《电子工艺技术》
2007年第3期125-129,共5页
Electronics Process Technology
基金
哈尔滨工业大学校基金资助项目
批准号:HIT.2003.50
