直流电作用下铜在液态锡里的溶解动力学

Kinetics of Copper Dissolution in Liquid Tin by Direct Current

本工作采用浸入法实验,通过施加直流电作用,研究了513~573K温度范围内铜在液态锡中的溶解动力学。对溶解后铜的溶解厚度以及Sn/Cu界面金属间化合物(IMC)层的厚度进行测量,对溶解激活能以及有效电荷Z^*进行计算,采用ComsolMultiphysics软件对电流引起的液态锡中的温度分布和流场分布进行模拟。实验结果表明:施加直流电对铜在液态锡中的溶解速率常数有显著的影响,随着电流密度增加,溶解速率增加,溶解激活能减小。电流的方向对铜的溶解和界面IMC层的生长也有影响,由于电迁移的作用,当电子流动的方向与铜的溶解方向一致时,溶解速率加快,界面IMC层的厚度变薄。在电流密度为240 A/cm^2时,铜在液态锡中的有效电荷Z^*随着温度的增加逐渐减小。

The dissolution kinetics of copper in liquid tin in the temperature range of 513~573 K were investigated under the influence of a DC current by immersion method.After dissolution,the dissolution thickness and the thickness of IMC layer at Sn/Cu interface were measured and the dissolution activation energy and effective charge Z^*were calculated.The temperature distribution and flow field of the liquid tin caused by the current were simulated by Comsol Multiphysics.It is found that the current has a marked effect on the dissolution rate constant.Correspondingly,the application of the current significantly decreases the activation energy of dissolution.Similarly,the direction of the DC current has an effect on dissolution of copper and the growth of IMC.When the electronic flow is in the direction of dissolution,a further increase in dissolution and a decrease in growth of IMC layer are observed which are attributed to electromigration.When the current density is 240 A/cm^2,the effective charge Z^*decreases with the increase of temperature.