(1. 义乌工商职业技术学院，金华 322000；
2. 西南石油大学 工程学院，南充 637001；
3. 北京航空航天大学 机械工程及自动化学院，北京 100084)
摘 要: 纳米Ag烧结因具有优异的导热和耐高温性，将是第三代宽禁带半导体芯片封装的理想的连接材料，如何选择合适的第二相以稳定高温服役过程中烧结层组织的演变，是当前Ag烧结技术面临的重要挑战之一。本文采用碳纳米管-石墨烯(CNT-G)来增强纳米Ag焊膏，通过分析烧结组织和接头剪切性能，研究添加相后对烧结接头的影响规律。结果表明：CNT-G增强纳米Ag焊膏的分解温度为250 ℃，焊膏中碳纳米管、石墨烯和Ag的含量为93%（质量分数）。随着烧结温度升高，大量颗粒之间形成烧结颈，使得烧结层的致密度逐渐提高，电阻率逐渐降低。CNT-G增强的纳米Ag焊膏可以在温度≥230 ℃、烧结压力5 MPa下实现SiC芯片和基板连接，其烧结层与芯片和基板都形成了良好冶金结合。
关键字: 纳米Ag焊膏；烧结连接；SiC芯片；微观组织
（1. Yiwu Industrial and Commercial College, Jinhua 322000, China;
2. School of Engineering, Southwest Petroleum University, Nanchong 637001, China;
3. School of Mechanical Engineering& Automation, Beihang University, Beijing 100084, China）
Abstract:Nano-Ag sintering is an ideal sintering materials for third-generation wide-band gap semiconductor chip packaging due to its excellent thermal conductivity and high temperature resistance. How to choose a suitable second phase to stabilize the evolution of the sintered layer structure during high-temperature operation is one of the important challenges of Ag sintering technology. In this paper, carbon nanotube-graphene (CNT-G) was used to reinforce the nano-Ag paste. The sintered microstructure, shear strength, and the influence of the added phase were analyzed. Results show that the decomposition temperature of CNT-G reinforced nano-Ag paste is 250 ℃, and the content of Ag and CNT-G is 93% (mass fraction). As sintering temperature increases, more and more particles form sintering necks, which gradually increases the density of the sintered body. The CNT-G reinforced nano-Ag paste can realize bonding SiC chip and DBC substrate at temperature of ≥230 ℃ and sintering pressure of 5 MPa.
Key words: nano-Ag paste; sintering; SiC chip; microstructure
