碱性铜抛光液在CMP工艺中的性能评估  

Evaluation of the Property for the Alkaline Copper Slurry in the CMP Process

作　　者：袁浩博 刘玉岭[1] 蒋勐婷 刘伟娟[1] 陈国栋[1] 

机构地区：[1]河北工业大学微电子研究所,天津300130

出　　处：《微纳电子技术》2014年第6期404-408,共5页Micronanoelectronic Technology

基　　金：国家中长期科技发展规划02科技重大专项资助项目(2009ZX02308)

摘　　要：研究了一种碱性铜抛光液,其基本组分是硅溶胶磨料、新型FA/O V型螯合剂、非离子表面活性剂和氧化剂(H2O2)。在压力为2 psi(1 psi=6.895 kPa)、抛头转速与抛盘转速分别为97和103 r/min、流量为300 mL/min的条件下,分析了铜膜去除速率随着螯合剂和氧化剂体积分数增加的作用规律。结果表明,加入体积分数2%的螯合剂和体积分数3%的氧化剂时,抛光液具有较好的自钝化能力和较高的铜膜去除速率。同时,研究了工艺参数在抛光过程中对去除速率和片内非均匀性(WIWNU)的影响,平坦化实验的抛光工艺选择压力1.5 psi、抛头和抛盘转速分别为87和93 r/min、流量300 mL/min。实验结果表明:此种抛光液在上述工艺条件下,抛光结束时剩余高低差为63.7 nm,具有较好的平坦化效果,对抛光液商业化提供了参考价值。An alkaline copper slurry consisting of the colloidal silica abrasive, novel FA/O V chelating agent, nonionic surface active agent and oxidizing agent （H202） was researched. The ini- tially polishing conditions were set as follows： the working pressure was 2 psi （1 psi = 6. 895 kPa）, the polishing head speed and plate speed was 97 and 103 r/min, respectively, and the flow rate was 300 mL/min. Under the above process conditions, the effects of the FA/O V chelating agent and H2O2 volume fractions on the copper removal rate were analyzed. The experi- mental results show that when the volume fractions of the FA/O V chelating agent and the H2O2 are 2% and 3%, respectively, the slurry has a good self-passivation ability and relative high removal rate. Meanwhile, the influences of the process parameters on the copper removal rate and within wafer non-uniformity （WIWNU） were also investigated. Based on the results, the working pressure of 1.5 psi, the polishing head speed of 87 r/rain, the plate speed of 93 r/min and the slurry flow rate of 300 mL/min were fixed to investigate the planarization of the copper slurry. The planarization experiment result shows that the residual step height is 63.7 nm, which indicates a good planarization performance for the slurry under the above process conditions. The results acquired from the above discussion provide a reference for the commercialization of the alkaline copper slurry.

关 键 词：碱性铜抛光液 去除速率 片内非均匀性(WIWNU) 高低差 平坦化 

分 类 号：TN305.2[电子电信—物理电子学]