Low-temperature grapho-epitaxial La-substituted BiFeO3 on metallic perovskite

• Published in: Nature Communications
• Main Authors: Sajid Husain, Isaac Harris, Guanhui Gao, Xinyan Li, Peter Meisenheimer, Chuqiao Shi, Pravin Kavle, Chi Hun Choi, Tae Yeon Kim, Deokyoung Kang, Piush Behera, Didier Perrodin, Hua Guo, James M. Tour, Yimo Han, Lane W. Martin, Zhi Yao, Ramamoorthy Ramesh
• Format: Article
• Language: English
• Published: Nature Portfolio 2024-01-01
• Online Access: https://doi.org/10.1038/s41467-024-44728-y

Abstract Bismuth ferrite has garnered considerable attention as a promising candidate for magnetoelectric spin-orbit coupled logic-in-memory. As model systems, epitaxial BiFeO3 thin films have typically been deposited at relatively high temperatures (650–800 °C), higher than allowed for direct integration with silicon-CMOS platforms. Here, we circumvent this problem by growing lanthanum-substituted BiFeO3 at 450 °C (which is reasonably compatible with silicon-CMOS integration) on epitaxial BaPb0.75Bi0.25O3 electrodes. Notwithstanding the large lattice mismatch between the La-BiFeO3, BaPb0.75Bi0.25O3, and SrTiO3 (001) substrates, all the layers in the heterostructures are well ordered with a [001] texture. Polarization mapping using atomic resolution STEM imaging and vector mapping established the short-range polarization ordering in the low temperature grown La-BiFeO3. Current-voltage, pulsed-switching, fatigue, and retention measurements follow the characteristic behavior of high-temperature grown La-BiFeO3, where SrRuO3 typically serves as the metallic electrode. These results provide a possible route for realizing epitaxial multiferroics on complex-oxide buffer layers at low temperatures and opens the door for potential silicon-CMOS integration.