Hung Han-Tang, Chang Fu-Ling, Tsai Chin-Hao, Liao Chia-Yi, Kao C R
Department of Materials Science & Engineering, National Taiwan University, Taipei 10617, Taiwan.
Materials (Basel). 2023 Sep 18;16(18):6263. doi: 10.3390/ma16186263.
Indium is considered a candidate low-temperature solder because of its low melting temperature and excellent mechanical properties. However, the solid-state microstructure evolution of In with different substrates has rarely been studied due to the softness of In. To overcome this difficulty, cryogenic broad Ar beam ion polishing was used to produce an artifact-free Cu/In interface for observation. In this study, we accomplished phase identification and microstructure investigation at the Cu/In interface after long-term thermal aging. CuIn was observed to grow at the Cu/In interface and proved to be a stable phase in the Cu-In binary system. The peritectoid temperature of the CuIn + In → CuIn reaction was confirmed to be between 100 and 120 °C. In addition, the growth rate of CuIn was discovered to be dominated by the curvature of the reactant CuIn/In phase and the temperature difference with the peritectoid temperature. Finally, a comprehensive microstructural evolution mechanism of the Cu/In solid-state interfacial reaction was proposed.
铟因其低熔点温度和优异的机械性能而被认为是一种低温焊料候选材料。然而,由于铟的柔软性,不同衬底上铟的固态微观结构演变很少被研究。为了克服这一困难,采用低温宽幅氩束离子抛光技术制备了无假象的铜/铟界面用于观察。在本研究中,我们完成了长期热老化后铜/铟界面的相鉴定和微观结构研究。观察到CuIn在铜/铟界面处生长,并被证明是铜-铟二元体系中的一个稳定相。CuIn + In → CuIn反应的包析温度被确定在100至120℃之间。此外,发现CuIn的生长速率受反应物CuIn/In相的曲率和与包析温度的温差支配。最后,提出了铜/铟固态界面反应的综合微观结构演变机制。