Unipolar and non-volatile RF switches using MoS2 by liquid-liquid interface assembly for millimeter wave applications

This study presents the first application-ready demonstration of radio-frequency (RF) switches based on memristors fabricated through a combination of electrochemical exfoliation and liquid-liquid interfacial assembly (EC-LL). This 2D layer fabrication method yields uniform, low-defect bilayer MoS₂ nanosheet networks without relying on high-temperature processes or hazardous gases typical of chemical vapor deposition (CVD), offering a low-cost and environmentally friendly route towards CMOS-compatible integration. Remarkably, the resulting devices exhibit robust unipolar resistive switching which simplifies biasing requirements and reduces power consumption. Reproducibility with retention of 104 sec, and endurance of 100 cycles is reported. RF measurements confirm reliable operation at millimeter wave (mmWave) frequencies across 10–110 GHz, demonstrating low insertion loss (0.42–0.9 dB), isolation >18 dB, and an intrinsic cut-off frequency of ~5.4 THz. Integration into Reconfigurable Intelligent Surface Unit Cells (RIS-UCs) further showcases the technology’s utility in next-generation mmWave communication systems, including 5G/6G and satellite applications. Simulations of a 24×24-element RIS panel confirm high gain (>21.6 dBi) and efficient beam steering (-60º, 60º degrees) over the 26.8–29.1 GHz band, while the ultra-low switching energy (~330 pJ per unit cell) enables zero static power consumption—critical for scalable and sustainable 6G infrastructure. This work establishes a new benchmark by delivering the first solution-processed, application-suitable 2D material in solid-state RF switches combining non-volatility, high-frequency operation, and CMOS integration potential. It marks a significant step toward reconfigurable, energy-efficient wireless communication platforms.