采用同步辐射源X射线衍射技术原位观测VLSI铝互连线的应力  

In-situ Observation of Stresses in VLSI Al Interconnects by Using the Synchrotron Radiation X-Ray Diffraction Technique

作　　者：吉元[1] 刘志民[2] 付厚奎[3] 李志国[3] 钟涛兴[2] 张虹[2] 吴月华[3] 付景永[1] 

机构地区：[1]北京工业大学固体微结构与性能研究所,北京100022 [2]北京工业大学材料科学与工程学院,北京100022 [3]北京工业大学电子信息与控制工程学院,北京100022

出　　处：《北京工业大学学报》2005年第5期514-518,共5页Journal of Beijing University of Technology

基　　金：国家基金委重点基金资助项目(69936020)军用模拟集成电路国防科技重点实验室基金资助项目(51439040203 QT0101).

摘　　要：为研究VLSI金属互连线的应力导致IC器件失效的问题,采用同步辐射源X射线衍射技术,原位测试了VLSI中Al互连线在电迁徙及加热条件下的应力变化.沉积态的Al互连线在室温下为拉应力.退火过程使拉应力逐渐减小,在300～350℃过程中由拉应力转为压应力.在电流密度为(3×105～4×106)A/cm2,275min的电徙动实验过程中,Al互连线阳极端由拉应力转变为压应力,并随后随着电流密度的增加而增加.此外,采用扫描电镜(SEM)观察了Al互连线的电迁徙失效特征及应力释放过程.In order to study the failure of IC devices induced by the stress in VLSI metal interconnect, In-situ observation of the stress changes of VLSI Al interconnect was studied under the electromigration and thermal conditions by using a synchrotron radiation x-ray diffraction technique. The tensile stress in deposited Al interconnects was measured in the room temperature. During the annealing process, the tensile stress gradually decreased and then conversed into the compress stress at the temperatures between 300℃ and 350 ℃. During the electronmigration tests in the range of 3 × 10^5 A/cm2 and 4 × 10^6 A/cm2 for 275 min, the tensile stress at the anode of Al interconnects changed into the compress stress, which then increased with the increasing of current density. Furthermore, the electronmigration failure characteristic and the stress relax of Al interconnects was observed by using the SEM.

关 键 词：同步辐射源X射线衍射 Al互连线 热应力 电迁徙 

分 类 号：TN306[电子电信—物理电子学]