提高羟基亚乙基二膦酸直接镀铜结合强度的研究

Improvement of Adhesion of Direct Copper Plating Layer from HEDP Bath

为了提高钢铁基体上羟基亚乙基二膦酸(HEDP)镀铜层的结合强度,采用电化学工作站进行阴极极化曲线和恒电流电位-时间曲线的测定,应用弯曲折断法进行临界起始电流密度(即保证镀层结合强度的最小初始电流)的测定和镀层结合强度的定量测定,探讨了辅助配位剂及相关工艺参数对镀层结合强度的影响。结果表明:辅助配位剂的加入提高了铜析出时的阴极极化,降低了临界起始电流密度,当用1A/dm2的电流密度进行起始电镀时,可使铁的表面在铜沉积前得到更充分的活化,使铜镀层与铁基体的结合强度提高到6416.38N/cm2,已接近铜上电镀铜的水平。介绍了电镀层结合强度的定量测定方法,探讨了提高镀层结合强度的电位活化机理。

In order to improve the adhesion between iron and copper plating from 1-hy-droxy ethylidene-1,1-diphosphonic acid( HEDP) bath, the ca-thodic polarization curves and potential-time curves were recorded, and the critical initial current density and the quantitative result of adhesion between substrate and copper plating were measured through bend-snap method. The effects of assistant complexing agent and some technological parameters were discussed on the adhesion. The results showed that the addition of the assistant complexing agent increased the cathodic polarization of copper solution, and decreased the critical current density. When copper plating at a constant current density of 1 A/dm2, the surface of iron was activated before the copper deposition, thus the adhesion between iron substrate and copper plating was increased to 6 416. 38 N/cm , which was close to the level of copper plating layer on copper. The quantitative testing of adhesion between substrate and plated layer was introduced, and the potential activation mechanism for the improvement of the adhesion of layer was discussed.