Transmission electron microscopy study of the failure mechanism of the diffusion barriers (TiN and TaN) between Al and Cu
详细信息 查看全文
- 作者：Soo-Hyun Kim
- 关键词：thin films ; diffusion ; compounds ; transmission electron microscopy (TEM) ; scanning/transmission electron microscopy (STEM)
- 刊名：Metals and Materials International
- 出版年：2017
- 出版时间：January 2017
- 年：2017
- 卷：23
- 期：1
- 页码：141-147
- 全文大小：
- 刊物类别：Chemistry and Materials Science
- 刊物主题：Metallic Materials; Operating Procedures, Materials Treatment; Magnetism, Magnetic Materials; Engineering Thermodynamics, Heat and Mass Transfer; Characterization and Evaluation of Materials; Continuu
- 出版者：The Korean Institute of Metals and Materials
- ISSN：2005-4149
- 卷排序：23
文摘
Failure mechanisms of transition metal nitride thin film diffusion barriers, such as TiN and TaN (10 nm in thickness), between Al and Cu were investigated by transmission electron microscopy (TEM), scanning transmission electron microscopy, and energy dispersive spectroscopy. After annealing at 450 °C during 30 min, the TiN diffusion barrier initially failed due to an interfacial reaction between TiN and Al forming TiAl3. When the annealing temperature was increased to 500 °C, Cu-Al intermetallic compounds were formed by the interdiffusion of Al and Cu through the diffusion barrier. In the case of the Al/TaN/Cu structure, no interfacial reaction products were observed after annealing up to 550 °C. On the other hand, it failed after annealing at 550 °C due to the inter-diffusion of Cu and Al through the diffusion barrier. TEM also identified Cu to be the rapid diffusing species in both systems. The results are discussed based on the thermodynamic stability of the interface predicted by the ternary phase diagram and the diffusion kinetics of Al and Cu through the diffusion barrier. The results show that both the thermodynamic stability of the diffusion barrier between Al and Cu and the diffusion kinetics of Al and Cu through the diffusion barrier, which are dependent on the microstructure of the diffusion barrier, should be considered carefully when selecting diffusion barrier materials between Al and Cu.