先进封装中铜-铜低温键合技术研究进展

Cu-Cu低温键合技术是先进封装的核心技术，相较于目前主流应用的Sn基软钎焊工艺，其互连节距更窄、导电导热能力更强、可靠性更优. 文中对应用于先进封装领域的Cu-Cu低温键合技术进行了综述，首先从工艺流程、连接机理、性能表征等方面较系统地总结了热压工艺、混合键合工艺实现Cu-Cu低温键合的研究进展与存在问题，进一步地阐述了新型纳米材料烧结工艺在实现低温连接、降低工艺要求方面的优越性，概述了纳米线、纳米多孔骨架、纳米颗粒初步实现可图形化的Cu-Cu低温键合基本原理. 结果表明，基于纳米材料烧结连接的基本原理，继续开发出宽工艺冗余、窄节距图形化、优良互连性能的Cu-Cu低温键合技术是未来先进封装的重要发展方向之一.

Research progress of low-temperature Cu-Cu bonding technology for advanced packaging

Low-temperature Cu-Cu bonding technology is the core technology for advanced packaging. Compared with the mainstream Sn-based soldering process, it can achieve finer pitch, higher electrical and thermal conductivity. In this paper, low-temperature Cu-Cu bonding technology for advanced packaging is reviewed. The research progress of low-temperature Cu-Cu bonding realized by thermal compression bonding and hybrid bonding is systematically summarized from the aspects of process flow, bonding mechanism and performance characterization. The advantages of the newly-developed nanomaterial sintering process in reducing bonding temperature and process requirements are further expounded. Mechanism of patterned nanowires, nano-porous frameworks and nanoparticles for low-temperature bonding are summarized. Low-temperature Cu-Cu bonding technology for advanced packaging are forecast.