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 (ZrO2-x) as a dielectric and molybdenum disulfide (MoS2) as a semiconductor layer. The ZrO2-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 x 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.