Sub-stoichiometric zirconium oxide as a solution-processed dielectric for reconfigurable electronics

Abstract

Reconfigurable devices that can switch functionalities could be used to overcome the limitations of miniaturized metal–oxide–semiconductor field-effect transistors. Conventional approaches typically involve the partial electrostatic modulation of two-dimensional semiconductors and use partial floating gates or dual-gate structures. Reconfigurable devices based on vertical van der Waals heterostructures have much simpler device structures, but lack a scalable assembly method. Here, we report a scalable reconfigurable device based on solution-processed van der Waals heterostructures. We vertically assemble thin films of sub-stoichiometric zirconium oxide (ZrO_2-x) as a dielectric and molybdenum disulfide (MoS₂) as a semiconductor layer. The ZrO_2-x/MoS₂ heterostructure provides simultaneous global and local gating within a single-gate transistor configuration, modulating the spatial electric field across the device in a reconfigurable manner. Under global gating conditions, the devices function as uniform field-effect transistors with an average field-effect mobility of 10 cm² V⁻¹ s⁻¹ and current on/off ratio of up to 10⁶. Under local gating conditions, the devices function as diodes, exhibiting a current rectification ratio of around 7 × 10⁴. By harnessing the reconfigurable characteristics, we achieve adjustable temporal photoresponse dynamics with a photoresponsivity of around 10⁵ A W⁻¹, high spatial uniformity and multi-spectral photodetection. We also use the approach to create a large-area reconfigurable optoelectronics array.