Researchers from King Abdullah University and the University of Barcelona have created memristive RF switches that operate at frequencies over 100 GHz.
Radiofrequency (RF) switches are electronic components that manage how RF signals move through different parts of circuits, such as switching signals on and off or changing their direction. These switches play a key role in many communication technologies, such as smartphones, cell towers, and wireless networks.
Researchers from King Abdullah University of Science and Technology, Universitat Autonoma de Barcelona, and other institutions have recently created memristive radiofrequency switches capable of operating at extraordinary frequencies over 100 GHz.
The researchers’ radiofrequency switches utilize memristors, two-terminal devices that change electrical resistance under specific stress, functioning as switches that toggle between an OFF state with high resistance and an ON state with low resistance. At frequencies above 100 GHz, achieving optimal performance necessitates addressing non-idealities, device parasitics, and overall performance through various IC components, including MEMS, transistors, diodes, varactors, and recently, memristors made from metal-insulator transition materials.
Developing wireless communication solutions above 100 GHz has unique benefits but also challenges. Controlled stress on single-layer 2D material memristors creates a conductive filament for low resistance in the ON state, supporting frequencies up to 480 GHz. However, they need more endurance and consistent yield. Lanza’s team addresses these with multilayer h-BN RF switches, managing conductive filaments in h-BN material through carefully applied voltage or current pulses, enhancing performance and reliability.
The team’s device employs metallic filaments disrupted by Joule heating, allowing electromagnetic signal switching under any stress polarity, enabling operation with positive, negative, or mixed voltages. This flexibility simplifies circuit integration and enhances the potential of multilayer h-BN memristors in advancing communication technologies. These memristive RF switches can function at high frequencies, supporting the development of faster mobile networks like 5G and 6G.
Using pulsed control, Lanza and his team achieved very low ON resistance in their devices, which is essential for high-frequency operation and has minimal variability across many cycles. These new memristive RF switches could soon be tested in various integrated circuits (ICs) for performance and practical potential, offering easy integration with existing electronics and fabrication processes.
Reference: Sebastian Pazos et al, Memristive circuits based on multilayer hexagonal boron nitride for millimetre-wave radiofrequency applications, Nature Electronics (2024). DOI: 10.1038/s41928-024-01192-2
