铜互连阻挡层化学机械抛光时互连线厚度的控制  

Control of thickness of interconnect line during chemical mechanical polishing of barrier layer on copper interconnect

作　　者：王海英 王辰伟 刘玉岭 赵红东 杨啸 陈志博 王雪洁 WANG Haiying;WANG Chenwei;LIU Yuling;ZHAO Hongdong;YANG Xiao;CHEN Zhibo;WANG Xuejie(School of Electronic and Information Engineering,Hebei University of Technology,Tianjin 300130,China;Tianjin Key Laboratory of Electronic Materials and Devices,Tianjin 300130,China;Science and Technology on Electro-Optical Information Security Control Laboratory,Tianjin 300308,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 [3]光电信息科学与工程控制和安全技术重点实验室,天津300308

出　　处：《电镀与涂饰》2023年第15期57-64,共8页Electroplating & Finishing

基　　金：国家自然科学基金(62074049);天津市科技计划项目(21YDTPJC00050)。

摘　　要：集成电路铜互连沟槽内互连线厚度(THK)影响着集成电路的性能,是集成电路制造工艺重要评定参数之一。基于无氧化剂、无缓蚀剂的碱性抛光液,研究了铜螯合剂FA/O II、介质促进剂柠檬酸钾(CAK)和抑菌剂1,2−苯并异噻唑啉−3−酮(BIT)对铜互连阻挡层化学机械抛光(CMP)中Cu去除速率和TEOS(正硅酸乙酯)去除速率及THK的影响。结果表明,THK受TEOS与Cu去除速率选择比的影响,与铜电阻呈负相关的关系。当FA/OⅡ质量分数为0.8%、CAK质量分数为1%及BIT质量分数为0.04%时,TEOS与Cu的去除速率比约为1.7,THK和电阻分别为225 nm和0.18Ω,均满足工业生产要求。The thickness of interconnect line(THK)in copper interconnect trench plays a crucial role in the performance of integrated circuit,making it an important evaluation parameter in IC manufacturing process.FA/O II as copper chelating agent,potassium citrate(CAK)as accelerator,and 1,2-benzisothiazolin-3-one(BIT)as bacteriostatic agent were added to an oxidant-and corrosion inhibitor-free alkaline slurry for chemical mechanical polishing(CMP)of the barrier layer of copper interconnect,and the effects of their mass fractions in the slurry on the removal rates of Cu and TEOS(tetraethyl orthosilicate)and THK were studied.The results showed that the removal rate ratio of TEOS to Cu influences the THK,and the THK is negatively correlated with the resistance of barrier layer.The removal rate ratio of TEOS to Cu was about 1.7 when the mass fractions of FA/O II,CAK,and BIT in the slurry were 0.8%,1%,and 0.04%,respectively,the THK was 225 nm,and the resistance of barrier layer was 0.18Ω,meeting the requirements of industrial production.

关 键 词：铜互联 阻挡层 化学机械抛光 互连线厚度 去除速率 电阻 

分 类 号：TN305.2[电子电信—物理电子学]