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arXiv · 2407.09740

Ferroelectric AlBN Films by Molecular Beam Epitaxy

Chandrashekhar Savant·Ved Gund·Kazuki Nomoto·Takuya Maeda·Shubham Jadhav·Joongwon Lee·Madhav Ramesh·Eungkyun Kim·Thai-Son Nguyen·Yu-Hsin Chen·Joseph Casamento·Farhan Rana·Amit Lal·Huili·Xing·Debdeep Jena
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Abstract

We report the properties of molecular beam epitaxy deposited AlBN thin films on a recently developed epitaxial nitride metal electrode Nb2N. While a control AlN thin film exhibits standard capacitive behavior, distinct ferroelectric switching is observed in the AlBN films with increasing Boron mole fraction. The measured remnant polarization Pr of 15 uC/cm2 and coercive field Ec of 1.45 MV/cm in these films are smaller than those recently reported on films deposited by sputtering, due to incomplete wake-up, limited by current leakage. Because AlBN preserves the ultrawide energy bandgap of AlN compared to other nitride hi-K dielectrics and ferroelectrics, and it can be epitaxially integrated with GaN and AlN semiconductors, its development will enable several opportunities for unique electronic, photonic, and memory devices.

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Chandrashekhar Savant, Ved Gund, Kazuki Nomoto, Takuya Maeda, Shubham Jadhav, Joongwon Lee, Madhav Ramesh, Eungkyun Kim, Thai-Son Nguyen, Yu-Hsin Chen, Joseph Casamento, Farhan Rana, Amit Lal, Huili, Xing, Debdeep Jena. 2024-07-13. Ferroelectric AlBN Films by Molecular Beam Epitaxy. https://doi.org/10.1063/5.0181217

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