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 Grace Xing, Debdeep Jena
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∼15μC/cm2 and coercive field Ec∼ 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.