Superior thermal stability of Ta/TaN bi-layer structure for copper metallization
Superior thermal stability of Ta/TaN bi-layer structure for copper metallization
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DOI：
10.1016/j.apsusc.2006.03.002
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发表时间：
2006-11
影响因子：
6.7
通讯作者：
Qi Xie;X. Qu;J. Tan;Yu-Long Jiang;Mi Zhou;Tao Chen;G. Ru
中科院分区：
文献类型：
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作者：
Qi Xie;X. Qu;J. Tan;Yu-Long Jiang;Mi Zhou;Tao Chen;G. Ru
Ta/TaN双层结构由于其对SiO2和Cu线都具有良好的粘附性，目前被用作超大规模集成电路（ULSI）互连线中的铜阻挡层。本文采用溅射技术制备了Cu、Ta和TaN薄膜。采用X射线衍射、俄歇电子能谱（AES）、X射线光电子能谱（XPS）和透射电子显微镜（TEM）对薄膜的热稳定性和微观结构进行了表征。结果表明，Ta/TaN双层结构比纯Ta或纯TaN膜具有更好的扩散阻挡性能。基于TaN层厚度与TaN晶化动力学之间的相关性，提出了Ta/TaN双层结构较好热稳定性的机理。描述了Ta/TaN双层结构在退火过程中的微结构演变。
Ta/TaN bi-layer structure is currently used in the ultra-large scale integrated circuits (ULSI) interconnect as barrier for copper because of its good adhesion to both SiO{sub 2} and Cu wire. In this work Cu, Ta and TaN layers were prepared by sputtering technology. X-ray diffraction, Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS) as well as transmission electron microscopy (TEM) were applied to characterize the thin film thermal stability and microstructure evolution. The results show that the Ta/TaN bi-layer structure has much better diffusion barrier properties than pure Ta or pure TaN film. A mechanism was proposed to explain the better thermal stability of the Ta/TaN bi-layer structure based on the correlation between TaN layer thickness and TaN crystallization kinetics. The microstructure evolution for Ta/TaN bi-layer structure during annealing was described.