Stress effect on the leakage current distribution of ferroelectric Al0.7Sc0.3N across the wafer

Stress effect on the leakage current distribution of ferroelectric Al0.7Sc0.3N across the wafer

Applied Physics Letters

10.1063/5.0159599

http://dx.doi.org/10.1063/5.0159599

Wanwang Yang, Li Chen, Minghua Li, Fei Liu, Xiaoyan Liu, Chen Liu, Jinfeng Kang

27 September 2023

Yang, W., Chen, L., Li, M., Liu, F., Liu, X., Liu, C., & Kang, J. (2023). Stress effect on the leakage current distribution of ferroelectric Al0.7Sc0.3N across the wafer. Applied Physics Letters, 123(13). https://doi.org/10.1063/5.0159599

This study presents an investigation into the stress effect on the leakage current in ferroelectric Al0.7Sc0.3N films by experiments and density functional theory (DFT) computations. The experiments are based on 8-in. 100 nm Al0.7Sc0.3N films obtained from pulsed DC co-sputter deposition technology, which exhibit non-uniform compressive in-plane stress across the wafers and similar distributions of leakage current, suggesting close dependence between each other. DFT computations revealed that stress affects leakage current in two ways: the level of traps introduced by nitrogen vacancy and the formation energy of nitrogen vacancy in Al0.7Sc0.3N. By considering both factors, the leakage current of Al0.7Sc0.3N films increases with larger compressive in-plane stress, as observed in the experimental results. Additionally, the DFT calculation results indicated that the leakage current is more sensitive to compressive stress compared to the tensile, and the minimum leakage current can be obtained with neutral in-plane stress. These findings provide a guideline for stress engineering to optimize the AlScN-based ferroelectric devices.

Publisher Copyright

This research / project is supported by the Science and Engineering Research Council of A*STAR - Ferroelectric Aluminum Scandium Nitride (Al1-xScxN) Thin Films and Devices for mm-Wave and Edge Computing
Grant Reference no. : A20G9b0135

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Yang, W., Chen, L., Li, M., Liu, F., Liu, X., Liu, C., & Kang, J. (2023). Stress effect on the leakage current distribution of ferroelectric Al0.7Sc0.3N across the wafer. Applied Physics Letters, 123(13). https://doi.org/10.1063/5.0159599 and may be found at https://doi.org/10.1063/5.0159599

https://oar.a-star.edu.sg/communities-collections/articles/21032

0003-6951
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Institute of Microelectronics