焦耳热对Cu/Ga-21.5In-10Sn/Cu液-固电极界面微观结构的影响

Effect of Joule Heat on Microstructure of Cu/Ga-21.5In-10Sn/Cu Liquid-Solid Electrode Interface

室温Ga基液态金属兼具金属的导电性和液体的流动性,是柔性电子器件的首选材料。在电子产品微型化趋势下,Ga基液态金属导体面临着更大的电流密度、更高的焦耳热效应等问题,严重影响着液-固电极界面的微观结构及结构稳定性。利用实验数据与数值模拟相结合的方法,通过改变通电过程中的换热介质研究了焦耳热对Cu/Ga-21.5In-10Sn/Cu液-固电极界面微观结构演化的影响。结果表明,在400 A/cm^(2)的电流密度下通电24 h后,Cu/Ga-21.5In-10Sn/Cu界面会生成CuGa2,阴极和阳极界面生成的CuGa2层厚度没有显著差异,并且在阴极Cu电极表面出现明显的溶蚀坑,表现出极性效应,而且通电过程中产生的焦耳热会导致阴极Cu电极表面溶蚀坑的快速生成。

Gallium-based liquid metal has both the conductivity of metal and the fluidity of liquid at room temperature,making it the preferred material for flexible electronic devices.In the trend of miniaturization of electronic products,Ga-based liquid metal conductors are faced with problems such as higher current density and higher Joule heating effect,which strongly affect the microstructure and struc-tural stability of liquid-solid electrode interface.Through the combination of experimental data and numerical simulation,the effect of Joule heat on the microstructure evolution of Cu/Ga-21.5In-10Sn/Cu liquid-solid electrode interface was investigated by changing the heat transfer medium during energization.The research results show that CuGa2 is formed at the Cu/Ga-21.5In-10Sn/Cu interface being energized for 24 h at a current density of 400 A/cm^(2).There is no significant difference in the thickness of the CuGa2 layer between the cathode and anode interfaces,but the corrosion pits formed by dissolution of the cathode Cu electrode are more pronounced,exhibiting a polarity effect.Besides,the Joule heat generated during the energization process can lead to the rapid formation of corrosion pits formed by dissolution on the surface of the cathode Cu electrode.