Nanosecond Magneto‐Ionic Control of Magnetism Using a Resistive Switching HfO2 Gate Oxide

• Published in: Advanced electronic materials Vol. 11; no. 3
• Main Authors: Jeong, Jimin, Park, Yeon Su, Kang, Min‐Gu, Park, Byong‐Guk
• Format: Journal Article
• Language: English
• Published: Wiley-VCH 01.03.2025
• Subjects: magneto‐ionic effect; resistive switching; spin‐orbit torque; voltage‐controlled magnetism
• ISSN: 2199-160X; 2199-160X
• DOI: 10.1002/aelm.202400535

Voltage‐controlled magnetism (VCM) offers an efficient operating method for various spintronic applications, with reduced power consumption compared to conventional current‐driven technologies. Among the VCM mechanisms, magneto‐ionic control provides large modulation and non‐volatile characteristics. However, its operating speed is limited to a microsecond timescale due to slow ion migration, which must be improved for practical device applications. Here, the nanosecond operation of magneto‐ionic VCM in a Ta/CoFeB/MgO/AlOx structure by introducing an HfO2 gate oxide with resistive switching characteristics is demonstrated. By inducing soft breakdown in the HfO2 gate oxide, the coercivity of the perpendicularly magnetized CoFeB can be controlled by 20% with a 20 ns gate voltage of ≈7 MV cm−1. This nanosecond magneto‐ionic VCM performance is maintained after repeated operations up to 10 000 cycles. Further, by utilizing an HfO2 gate in a spin‐orbit torque (SOT) device, the ability to control field‐free SOT switching polarity with nanosecond gate voltages is demonstrated. These findings provide a novel pathway to realize nanosecond, non‐volatile VCM for low‐power spintronic applications. A nanosecond operation of magneto‐ionic control of magnetism in a Ta/CoFeB/MgO structure by introducing a HfO2 gate oxide with resistive switching is demonstrated. After inducing a soft breakdown in the HfO2 gate, the coercivity of the CoFeB layer is controlled by 20% with a 20 ns gate voltage, which remains effective for up to 10 000 operations.