摘要
在ULSI多层铜布线中,由于钽与铜在物理及化学性质上的差别导致这两者的CMP去除速率不同,从而在抛光结束后出现蝶形坑等缺陷,影响器件性能。通过实验分析碱性抛光液中磨料、螯合剂、氧化剂、pH值、活性剂对铜与钽CMP选择比的影响。根据铜与钽的CMP去除机理,从实验结果分析出对铜、钽去除速率影响较为明显的成分,调节这些成分得到特定配比的抛光液,分别实现了铜与钽的去除速率相等、铜的去除速率大于钽、铜的去除速率小于钽。使用上述铜去除速率小于钽的抛光液对12英寸(1英寸=2.54 cm)图形片进行抛光,通过原子力显微镜观察,证明了这种抛光液能有效地修复多层布线CMP中的蝶形坑等缺陷。
In multilayer copper wiring of ULSI,the CMP removal rates of Cu and Ta are different caused by different physical and chemical properties for the two substances,thus the defect such as the dishing appears after polishing,which will affect the device performance.The effects of the abrasive,chelating agent,oxidizer,pH value and active agent on the selectivity of Cu and Ta were analyzed through the experiment.Based on Cu and Ta CMP removal mechanism,the ingredients obviously affecting the removal rates of Cu and Ta were analyzed from experimental results.The slurry with specific proportion was obtained through adjusting these ingredients.The results of equal,larger and lesser removal rates of Cu compared to that of Ta were achieved,respectively.Using the slurry that Cu removal rate is less than that of Ta to polish the 12 inch（1 inch=2.54 cm） wafer,and the result of the atomic force microscope shows that the slurry can repair the defects such as dishing in multilayer wiring CMP effectively.
出处
《微纳电子技术》
CAS
北大核心
2012年第11期755-761,共7页
Micronanoelectronic Technology
基金
国家中长期科技发展规划02科技重大专项(2009ZX02308)
