双氧水在碱性抛光液中的稳定性研究

Study of the Stability of H_2O_2 in Alkaline Slurry

氧化剂是铜互连化学机械抛光液的重要组成部分,是决定抛光速率和平坦化效率的重要影响因素。双氧水(H2O2)是抛光液中最常用的氧化剂,其稳定性是评估抛光液性能的重要指标之一,直接关系到抛光液的寿命及其是否可以产业化。针对抛光速率、抛光液的pH值以及抛光后表面质量进行考察,分析了这三方面随抛光液放置时间的变化规律,从而得到H2O2在碱性抛光液中的稳定性规律。实验结果表明,抛光液主要成分的体积分数分别为硅溶胶2.5%、螯合剂1%、氧化剂1%时,抛光液最稳定,寿命可以达到24 h,满足工业化生产要求。

Oxidant is an important part of the slurry for Cu CMP,and has a great impact on the material removal rate and planarization efficiency.Hydrogen peroxide（H2O2） is widely used as the oxidant of slurry,and the stability of H2O2 is an important index to assess the performance of slurry,which is directly related to the lifetime and industrialization of the slurry.The polishing rate,pH value and surface quality were investigated.And the variation regulation with the storage time was analyzed.The stability regulation of H2O2 in alkaline slurry was obtained.The experimental results show that the slurry is most stable when the volume fraction of main ingredients of the slurry is 2.5% colloidal silica abrasive,1% chelating agents,1% oxidant.The lifetime can be reached 24 h,to meet the requirements of industrial production.