无氧铜表面特定清洗液的腐蚀机制及溶液特性

目的通过无氧铜特定清洗液的溶液配方实验、腐蚀机制测定以及清洗液浓度表征,为实现无氧铜稳定清洗提出技术方案。方法采用铬酐和浓硫酸互配进行溶液配方实验并采用扫描电镜形貌和腐蚀速率对结果进行对比分析;采用电化学循环伏安法研究了铜浓度对腐蚀速率的影响;采用EDTA络合滴定法测定铜浓度和氧化还原滴定法测定六价铬浓度进行了分析。结果 60~80 g/L铬酐+40~60 m L/L硫酸+余量水的溶液清洗可以获得均一稳定的表面,其中铬酐发挥着氧化剂的作用,硫酸发挥着调整酸度的作用;适当的铜离子浓度对化学反应有促进作用,随着铜离子质量浓度增大至5 g/L以上,腐蚀动力减缓,腐蚀速率减慢。结论提出了无氧铜稳定清洗的合适浓度,得出了腐蚀机制及溶液特性的具体结果。

Corrosion Mechanism and Solution Properties of Specific Cleaning Solu-tion for Oxygen-free Copper Surface

Objective: The solution formula and corrosion mechanism was studied so as to put forward of the technical scheme of the oxygen free copper cleaning. Method :Solution formulation of cleaning oxygen free copper was studied by using chromic anhydride and sulfuric acid and results was compared and analyzed by SEM and corrosion rate. Effects of copper concentration on the corrosion mechanism was studied by the method of electrochemical cyclic voltammetry. Copper concentration and chrome concentration in the solution was analyzed by the method of titration. Results : solution with chromic anhydride of 60~80 g/L and sulfuric acid of 40~60ml/L is feasible for cleaning, which can obtain a uniform and stable surface. Chromic anhydride plays an important role because of its strong oxidation and sulfuric acid plays an important role in adjusting the acidity of the solution and controlling chemical equilibrium in solution. Concentration of copper ion has obvious effect on the chemical reaction kinetics and mechanism of corrosion. A small amount of copper ion concentration has a stimulating effect on the chemical reaction and the excessive concentration of copper ions(>5 g/L) has inhibitory effect on the chemical reaction. Copper concentration can be analyzed by controlling the determination condition of EDTA complexometric titration and chrome concentration can be analyzed by redox titration. Conclusion: The suitable ratio of oxygen free copper stable cleaning was proposed and the concrete results of the corrosion mechanism and the solution characteristics were obtained.