pH值对低磨料碱性铜抛光液稳定性的影响

Effects of p H Value on the Stability of the Low Abrasive Alkaline Copper Polishing Slurry

稳定性是衡量化学机械抛光（CMP）中抛光液性能的一个重要指标,低磨料和低p H值是抛光液发展的方向。研究了不同p H值对低磨料碱性铜抛光液稳定性的影响。选取了磨料质量分数为1%的抛光液,加入磷酸调节p H值,得到p H值分别为7.3,8.11,9.21,10.02和11.04抛光液,测量比较了各组抛光液随存放时间的变化其p H值、磨料粒径、Zeta电位和铜去除速率的变化。结果表明,低磨料碱性铜抛光液的p H值随时间的延长而降低,磨料粒径也随存放时间的延长而变大,抛光液的Zeta电位的绝对值随p H值的降低而降低,铜的去除速率随抛光液的存放时间的增加而降低,当p H值为9.21~10.02时,抛光液存放时间超过48 h。

The stability is an important indicator to measure the performance of slurry in chemical mechanical planarization（ CMP）,low-abrasive and low-p H value are the developing direction of the slurry. The influences of different p H values on the stability of the alkaline copper polishing slurry were studied. The polishing slurry with the abrasive quality fraction of 1% was selected when added phosphoric acid,then adjusted p H values,the polishing slurry with different p H values of 7. 3,8. 11,9. 21,10. 02 and 11. 04 were obtained. And the p H value,abrasive particle size,Zeta potential and the copper removal rate were measured and compared with the changes of the storage time. The results show that the p H value of the low abrasive alkaline copper polishing slurry decreases with the increase of the storage time,but the abrasive particle size of the slurry becomes larger,and the Zeta potential absolute value of the slurry decreases with the decrease of p H value,the removal rate of copper reduces with the increase of the storage time,and the storage time of the polishing slurry with p H values of 9. 21- 10. 02 is more than 48 h.