微/纳尺度Cu-Sn界面冶金行为研究进展

doi:10.3901/JME.2022.02.223

摘要/Abstract

摘要： 随着电子芯片封装尺度高度集成化和功能化，对芯片互连结构的性能需求越来越高。而三维封装互连结构是实现多芯片间系统集成的关键技术之一，微/纳尺度Cu-Sn互连结构是实现三维封装互连的重要方向。重点阐述了电子封装中Cu-Sn互连结构值得关注的几种界面动力学行为，分别为固-液界面Cu₆Sn₅的生长；Cu-Sn界面层状IMCs固态老化；微凸点孔隙型Cu₃Sn的生长动力学；1 μm立柱式Cu-Sn界面IMCs生长；一维Cu/Sn纳米线的界面动力学。此外，随着互连结构尺度的减小，纳米尺度金属间化合物烧结连接等一些有关Cu-Sn界面冶金行为也在不断开展相关研究。最后，根据近年来微/纳尺度Cu-Sn界面冶金行为领域的研究进展，评述了该领域面临的挑战和展望。旨在厘清尺寸效应下的Cu-Sn界面生长动力学的主导机制，对实现三维集成电路的优质互连有着重要意义。

关键词: 三维封装, 互连结构, 微/纳尺度, Cu-Sn界面, 界面动力学

Abstract: With the higher-density integration and greater functionality of electronic chips, the performance requirements for chip micro-interconnection structures are getting higher and higher. The three-dimensional package interconnection structure is one of the critical technologies to achieve the systematic integration between multiple chips, and the micro/nano-scale Cu-Sn interconnect structure is considered to be an important development direction of the three-dimensional package interconnect structure. The focuses on the dynamic behavior of solder joint interfacial reactions in electronic packaging technology which are of wide interest. Growth of Cu₆Sn₅ at the solid-liquid interface; Layer-type growth of IMC in solid-state aging at the Cu-Sn interface; Growth kinetics of porous-type Cu₃Sn in μ-bumps; 1μm pillar-type growth of Cu-Sn IMCs; Interfacial kinetics of one-dimensional Cu/Sn nanowires. Further, with the reduction of interconnection structure size, the metallurgical behavior of Cu-Sn, such as nano-scale intermetallic compound sintering connection, was also constantly being studied. Finally, according to the research progress in the field of the metallurgical behavior of the micro/nano-scale Cu-Sn interface in recent years, this paper comprehensively reviews the challenges and prospects in this field. The purpose is to clarify the dominant mechanism of size effect the metallurgical behavior of Cu-Sn interface,and provide the important implications for high quality interconnection of 3D Integrated circuit.

Key words: three-dimensional package, interconnect structure, micro/nano scale, Cu-Sn interface, dynamic behavior

中图分类号:

TG425

陈捷狮, 王佳宁, 张志愿, 张培磊, 于治水, 余春, 陆皓. 微/纳尺度Cu-Sn界面冶金行为研究进展[J]. 机械工程学报, 2022, 58(2): 223-235.

CHEN Jieshi, WANG Jianing, ZHANG Zhiyuan, ZHANG Peilei, YU Zhishui, YU Chun, LU Hao. Advances in Metallurgical Behavior of Micro/nano-scale Cu-Sn Interface[J]. Journal of Mechanical Engineering, 2022, 58(2): 223-235.

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