基于正交实验法的Cu/Ta/TEOS碱性抛光液的优化  

Optimization of the Cu/Ta/TEOS Alkaline Slurry Based on Orthogonal Experiment

作　　者：徐奕 刘玉岭 王辰伟 马腾达 Xu Yi;Liu Yuling;Wang Chenwei;Ma Tengda(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》2019年第2期157-166,共10页Micronanoelectronic Technology

基　　金：国家中长期科技发展规划重大专项资助项目(2009ZX02308);河北省自然科学基金青年基金资助项目(F2015202267);天津市自然科学基金资助项目(16JCYBJC16100);河北工业大学优秀青年科技创新基金资助项目(2015007)

摘　　要：研究了碱性阻挡层抛光液中各组分对Cu、Ta和正硅酸乙酯(TEOS)去除速率的影响。通过单因素实验分别考察了磨料、FA/OⅡ螯合剂、KNO3和FA/OⅡ表面活性剂质量分数和H2O2体积分数对Cu、Ta和TEOS去除速率的影响,再结合正交实验研发了磨料质量分数为20%、FA/OⅡ螯合剂质量分数为2%、H2O2体积分数为0.1%,KNO3质量分数为1.5%、FA/OⅡ表面活性剂质量分数为2%的碱性阻挡层抛光液,该抛光液的Cu、Ta和TEOS的去除速率选择比为1∶1.47∶1.65。对4片12英寸(1英寸=2.54 cm)65 nm铜互连图形片的M4层进行阻挡层抛光,结果显示,铜沟槽内剩余铜膜厚度约为300 nm (目标值),图形片表面缺陷数目在10颗左右,碟形坑和蚀坑深度分别由52.3 nm和40 nm降至19.9 nm和18.4 nm,铜的表面粗糙度由4.4 nm降至1.9 nm。The effects of the components of alkaline barrier slurry on the removal rates of Cu,Ta and tetraethoxysilane(TEOS)were researched.The effects of the abrasive mass fraction,FA/OⅡchelating agent mass fraction,H2 O2 volume fraction,KNO3 mass fraction and FA/OⅡsurfactant mass fraction on the removal rates of Cu,Ta and TEOS were investigated with the singlefactor experiment,respectively.The alkaline slurry with the abrasive mass fraction of 20%,FA/O Ⅱchelating agent mass fraction of 2%,H2 O2 volume fraction of 0.1%,KNO3 mass fraction of 1.5%,FA/O Ⅱsurfactant mass fraction of 2% was developed by combining orthogonal experiment.The selectivity of removal rate ratio of Cu,Ta and TEOS is 1∶1.47∶1.65.The M4 layers of the four 12 inches(1 inch=2.54 cm)pattern wafers with 65 nm technology node and copper interconnect were subjected to barrier polishing.The results show that the residual copper film thickness in the copper trench is about 300 nm(target),the number of the pattern surface defects are about 10,the depths of dishing pit and erosion pit decrease from52.3 nm to19.9 nm and from40 nm to 18.4 nm,and the surface roughness of copper reduce from4.4 nm to1.9 nm.

关 键 词：Cu/Ta/TEOS 去除速率 碱性阻挡层 抛光液 单因素实验 正交试验 

分 类 号：TN305.2[电子电信—物理电子学]