Kinetics of Copper Dissolution in Liquid Tin by Direct Current

Abstract:

In this article, the dissolution kinetics of copper in liquid Tin at temperatures in the range 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. It is found that the current had a marked effect on the dissolution rate constant. Correspondingly, the application of the current significantly decreased the activation energy of dissolution. Similarly,the direction of the DC current was shown to have an effect on dissolution and the growth of IMC. When the electronic flow was in the direction of dissolution, a further increase in dissolution and a decrease in growth of IMC layer were observed and attributed to electromigration. When the current density was 240 A/cm_², the effective charge Z_^* decreased with the increased of temperature.

Key words:Electromigration; Dissolution; Activation energy; Effective charge