多层空气隙Cu互连结构耦合电容的优化.pdfVIP

、 Package,Test and Equipment doi:10.3969/j.issn.1003-353x.2010.07.025 Cu 姚 一杰, 汪辉 (上海交通大学微电子学院, 上海200240) :随着超大规模集成电路特征尺寸不断缩小, 多层Cu 互连之间的RC 延迟成为一个越 越严重的问题。由于低介电常数 (low-k )材料配合空气隙 (air gap)结构可用于降低Cu 互连 导线间的耦合电容从而改善RC延迟特性, 建立了单层和多层空气隙Cu 互连结构的有限元分析 模型, 以研究空气隙结构尺寸与互连介质等效介电常数的关系。结果表明, 在单层空气隙Cu 互 连结构中, 通过增加互连导线间空气隙的结构尺寸可以减小Cu 互连结构中的耦合电容, 进而改 善RC延迟特性;在多层空气隙Cu互连结构中, 通过改变IMD 和ILD 中空气隙的尺寸结构可以 得到RC延迟性能优化的多层空气隙Cu 互连结构。 :铜互连;空气隙;耦合电容;介电常数;有限元分析 :TN303　　:A 　　:1003-353X (2010)07-0710-05 Coupling Capacitance Optimizing of Multilayer Air Gap Copper Interconnect Structure Yao Yijie, Wang ui (School of Microelectronics, Shanghai Jiao Tong University, Shanghai 200240, China) Abstract:As the critical dimension of very large-scale integrated circuit (VLSI)shrinks, the RC delay between multilayer copper interconnects becomes a more and more serious problem.The coupling capacitance between copper interconnects can be reduced effectively by using low-k material and introducing air gap structure.Finite element analyzing models of a single-layer and a multilayer air gap copper interconnect structure were built to research the interconnect dielectric constant with different dimensions of air gap structures.The results show that in monolayer interconnect structure, the coupling capacitance between copper interconnects could be reduced by increasing the size of air gap structure, and then improve the RC delay performance.While in multilayer interconnect structure, RC delay performance can be improved by transforming the sizeof air gap structure in IMD and ILD. Key words:copper interconnection;air gap;coupling capacitance;dielectric constant;finiteelement analysis EEACC:2570A