Cu6Sn5的生长动力学
(1. 河南科技大学 材料科学与工程学院，洛阳 471003；
2. 河南省有色金属材料科学与加工技术重点实验室，洛阳 471003)
摘 要: 利用X射线衍射分析仪、JSM-5610LV扫描电镜及能谱分析研究钎焊和时效过程中低银Sn-2.5Ag- 0.7Cu(0.1RE)/Cu焊点界面区显微组织和Cu6Sn5金属间化合物的生长行为。结果表明：钎焊过程中焊点界面区Cu6Sn5金属间化合物的厚度是溶解和生长两方面共同作用的结果；随着时效时间的延长，焊点界面区Cu6Sn5的形貌由扇贝状转变为层状，其长大动力学符合抛物线规律，由扩散机制控制；添加0.1%稀土元素能有效减慢界面Cu6Sn5金属间化合物在钎焊及时效过程中的长大速度，可改变焊点裂纹的起源位置，提高其可靠性。
关键字: Sn-2.5Ag-0.7Cu(0.1RE)钎料；Cu6Sn5；钎焊；时效；微观组织；长大动力学
Sn-2.5Ag-0.7Cu(0.1RE)/Cu solder joint interface
（1. School of Materials Science and Engineering, Henan University of Science and Technology, Luoyang 471003, China;
2. The Key Laboratory of Non-ferrous Materials Science and Processing Technic of Henan Province,
Luoyang 471003, China）
Abstract: The microstructure and growth behavior of Cu6Sn5 intermetallic compound (IMC) of low Ag content Sn-2.5Ag-0.7Cu(0.1RE)/Cu solder joint interface were investigated by using the X-ray diffraction, JSM-5610LV scanning electronic microscope and energy spectrum analysis. The results show that the Cu6Sn5 thickness of the solder joint interface is decided by its diffraction and growing during the soldering. With the aging time increasing, the Cu6Sn5 micrograph of the solder joint interface can be changed from the scallop-like to the shape-layer, and the growing dynamics is coincidence with the law of parabola and its growing behavior is controlled by diffusion. With adding tiny rare earth(0.1RE) in the Sn-2.5Ag-0.7Cu solder alloy, the Cu6Sn5 growing rate of the solder joint can be effectively reduced during the soldering and aging period, and the crack initiation place can be changed, so the reliability of the solder joint can be greatly improved.
Key words: Sn-2.5Ag-0.7Cu(0.1 RE) solder alloy; Cu6Sn5; soldering; aging; microstructure; growing dynamics
