Identifying the Limits of Strain Engineering in NaNbO3 Ultrathin Films

Identifying the Limits of Strain Engineering in NaNbO3 Ultrathin Films

ACS Applied Materials & Interfaces

10.1021/acsami.5c09069

https://doi.org/10.1021/acsami.5c09069

Shengwei Zeng, Khuong Phuong Ong, Samantha Faye Duran Solco, Zhi Shiuh Lim, Qibin Zeng, Baichen Lin, Jiangbo Luo, Wenting Zhao, Tiancheng Luo, Weifan Cai, Zhen Ye, Celine Sim, Chee Kiang Ivan Tan, Seeram Ramakrishna, Yeng Ming Lam, Ariando Ariando, Huajun Liu

General Materials Science

16 July 2025

Zeng, S., Ong, K. P., Solco, S. F. D., Lim, Z. S., Zeng, Q., Lin, B., Luo, J., Zhao, W., Luo, T., Cai, W., Ye, Z., Sim, C., Tan, C. K. I., Ramakrishna, S., Lam, Y. M., Ariando, A., & Liu, H. (2025). Identifying the Limits of Strain Engineering in NaNbO3 Ultrathin Films. ACS Applied Materials & Interfaces, 17(30), 43227–43234. https://doi.org/10.1021/acsami.5c09069

Epitaxial NaNbO3 ultrathin films are grown on single crystal substrates with a wide range of compressive (-6.24%) and tensile (+7.13%) strain. High-resolution X-ray diffraction reveals a coherently strained state of NaNbO3 thin films within the strain range from -1.42 % to 1.86 %, beyond which the films are in relaxed states. This is accompanied by a change in the growth mode from step-flow growth in strained films to coalesced island growth in relaxed films. Piezoresponse force microscopy measurements, including domain writing and reading, reveal a single vertical ferroelectric domain for the compressive films, while the tensile films exhibit a mixture of multiple vertical domains. The first-principles calculations confirm the stability of the strained NaNbO3. Our results provide important information for the understanding and engineering of strained functional thin films.

Publisher Copyright

This research / project is supported by the National Research Foundation - Competitive Research Program
Grant Reference no. : NRF-CRP28-2022-0002

This research / project is supported by the A*STAR - Manufacturing, Trade, and Connectivity Individual Research Grant
Grant Reference no. : M22K2c0084

This research / project is supported by the A*STAR - Central Research Fund
Grant Reference no. :

This research / project is supported by the Ministry of Education - Academic Research Fund Tier 2 and 3
Grant Reference no. : MOE-T2EP50121-0018, MOE-T2EP50123-0013, MOE-MOET32023-0003

This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Applied Materials & Interfaces, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see 10.1021/acsami.5c09069.

https://oar.a-star.edu.sg/communities-collections/articles/23156

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Institute of Materials Research and Engineering