抛光时间对多层铜布线阻挡层CMP效果的影响  

Influence of Polishing Time on the CMP Effect of Multi-Layer Copper Wiring Barrier Layer

作　　者：刘光耀 王辰伟 周建伟 魏艺璇 张新颖 刘志 刘玉岭 Liu Guangyao;Wang Chenwei;Zhou Jianwei;Wei Yixuan;Zhang Xinying;Liu Zhi;Liu Yuling(School of Electronic and Information Engineering,Hebei University of Technology,Tianjin 300130,China;Tianjin Key Laboratory of Electronic Materials and Devices,Tianjin 300130,China)

机构地区：[1]河北工业大学电子信息工程学院,天津300130 [2]天津市电子材料与器件重点实验室,天津300130

出　　处：《微纳电子技术》2023年第2期298-304,共7页Micronanoelectronic Technology

基　　金：国家自然科学基金(62074049);河北省自然科学基金(E2019202367)。

摘　　要：为了提升多层铜布线阻挡层化学机械抛光(CMP)的平坦化效果,以获得平坦度高和质量好的表面,研究了不同抛光时间对阻挡层抛光后平坦化效果和表面质量的影响。CMP实验使用自主研发的碱性抛光液,固定抛光液组分不变,在60 s、40 s+20 s与30 s+30 s三种不同抛光时间下对阻挡层材料和图形片进行了CMP实验。实验结果表明,改变抛光时间可以提高Cu去除速率和降低正硅酸乙酯(TEOS)去除速率;其中40 s+20 s抛光后碟形坑和蚀坑深度修正分别约为40 nm和20 nm;铜沟槽内铜线条剩余厚度为225.7 nm,基本与工业生产目标值225 nm相匹配;图形片CMP后表面缺陷数量降低至189颗;铜镀膜片抛光后表面粗糙度降低至0.351 nm。To improve the planarization effect of the chemical mechanical polishing(CMP)of multi-layer copper wiring barrier layer to obtain the surfaces with high smoothness and good quality,the influences of different polishing time on the planarization effect and surface quality of barrier layer after polishing were studied.A self-developed alkaline slurry was used in the CMP experiments,and the component of slurry is constant.The CMP experiments were carried out on the barrier layer material and the pattern wafer with three different polishing time of 60 s,40 s+20 s and 30 s+30 s.The experimental results show that changing the polishing time can improve the Cu removal rate and reduce the tetraethyl orthosilicate(TEOS)removal rate.After 40 s+20 s polishing,the depth corrections of dishing and erosion are about 40 nm and 20 nm,respectively.The remaining thickness of the copper lines in the copper trench is 225.7 nm,which basically matches the industrial production target value of 225 nm.The number of surface defects on the pattern wafer after CMP are reduced to 189.The surface roughness of the copper blanketed wafer after polishing is reduced to 0.351 nm.

关 键 词：化学机械抛光(CMP) 铜布线 阻挡层 抛光工艺 碱性抛光液 表面质量 

分 类 号：TN305.2[电子电信—物理电子学]