【Device Papers】Surface-asymmetric dual-channel thin-film transistors based on wafer-scale printed quasi-2D gallium oxide

      Researchers from University of Chinese Academy of Sciences have published a dissertation titled " Surface-asymmetric dual-channel thin-film transistors based on wafer-scale printed quasi-2D gallium oxide " in Applied Materials Today.

Abstract

      Ultrathin transparent conducting oxides are promising for low-temperature transparent electronics. Here, we report a wafer-scale liquid metal printing strategy to produce quasi-2D gallium oxide films. The printed films exhibit intrinsic surface asymmetry, featuring a nanoparticle-decorated surface with highly conductive boundary behavior and a pristine semiconducting surface that remains gate-tunable. Coplanar measurements reveal pronounced surface-selective transport, which is rationalized by nanoparticle-modulated interfacial states, local potential redistribution, and barrier control in the nanoparticle-decorated channel. Leveraging this thickness-direction electronic asymmetry, we construct a dual-channel thin-film transistor that enables gate-triggered switching of the dominant transport pathway within a single-film platform. The device achieves a high field-effect mobility of 82 cm²·V⁻¹·s⁻¹ and a small subthreshold swing of 195 mV/dec. These results demonstrate wafer-scale liquid metal printing as a feasible route for surface-asymmetric dual-channel oxide electronics and suggest the potential of q-2D GaO_x films for future transparent oxide electronic applications.

DOI：

https://doi.org/10.1016/j.apmt.2026.103353