超深亚微米铜/低k互连应力迁移失效行为分析与寿命模型

项目名称： 超深亚微米铜/低k互连应力迁移失效行为分析与寿命模型

项目编号： No.60806034

项目类型： 青年科学基金项目

立项/批准年度： 2009

项目学科： 生物科学

项目作者： 吴振宇

作者单位： 西安电子科技大学

项目金额： 23万元

中文摘要： 本项目旨在研究超深亚微米Cu/低k互连应力迁移失效行为，分析超深亚微米Cu/低k互连应力迁移的失效模式、空位主导扩散路径、驱动力及其扩散机制，建立基于空位扩散、应力动态演变和应力释放-空洞生长能量转化机制等多因素耦合的应力迁移失效寿命模型，基于微观结构因素研究热-电综合应力条件下的互连质量输运失效问题，同时进行互连微观结构模拟与表征以及失效物理参数提取技术研究工作，并利用失效试验结果进行模型验证和优化。本项目在国内外首次提出基于扩散蠕变机制将应力演变和空洞生长动态联系起来研究空洞生长的具体微观过程，建立基于空位扩散、应力动态演变和应力释放-空洞生长能量转化机制等多因素耦合的应力迁移失效寿命模型，同时从微观结构因素角度出发建立铜互连热-电综合应力失效模型，较好地解释了铜互连热-电综合应力失效寿命随互连长度变化出现的饱和波动现象，为揭示超深亚微米铜/低k应力迁移规律奠定理论和实验基础，为实际应用中超深亚微米Cu/低k互连应力迁移失效寿命预测、互连结构与工艺优化、互连可靠性评估等提供关键技术支持。

中文关键词： 互连；应力迁移；失效

英文摘要： This project aims at studying stress-induced voiding in deep sub-micron Cu/low-k interconnects. The failure modes, dominant diffusion path and driving force of vacancies for stress migration in deep sub-micron Cu/low-k interconnects have been analyzed. A stress-induced voiding model has been built by integration of coupling factors including vacancy diffuion,dynamic stress evolution,and energy balance betwwen stress release and void growth. The microstrucutre modeling and characterization has been carried out. The method to obtain physical parameters for stress migration failures has been proposed. And verfication and optimazion for stressmigration model has also been done. This project has proposed to build stressmigration model based on the N-H mechanism and energy balance between stress release and void growth. A thermal and electrical stressing model for interconnect failure has been built from a microstructure point of view which explains the saturation phenomenon during variation in lifetime with interconnect length. These results provides solid theroetical and experimental bases to understand stress-induced phenomena of Cu/low-k interconnect and key supports for lifetime prediction, desigan and process optimization, and reliability evaluation of Cu/low-k interconnects.

英文关键词： Interconnect;Stress migration;Failure