Coplanar Lateral Gating MoS2 on SrTiO3: A Unified Platform for Classical and Quantum Devices

Abstract

Atomically thin transition-metal dichalcogenides, such as MoS2, offer a promising route to surpass the scaling limits of silicon owing to their excellent electrostatic control and resilience to short-channel effects. Realizing this potential depends critically on gate-stack engineering, where strong gate coupling must be achieved without compromising the pristine two-dimensional interface. Here, we demonstrate a coplanar lateral-gating architecture for MoS2 field-effect transistors fabricated directly on single-crystal SrTiO3. The exceptionally high permittivity of SrTiO3 enhances gate-channel coupling. The coplanar geometry eliminates the need for a separate gate insulator, reducing interface disorder. Owing to the quantum paraelectric nature, the SrTiO3 dielectric constant increases upon cooling, enhancing the gate coupling, leading to a decrease in threshold voltage and subthreshold swing an effect that contrasts with conventional FET architectures. The dielectric-free MoS2 surface, combined with enhanced electrostatic control, makes this architecture a promising platform for low-power two-dimensional electronics and cryogenic quantum devices.