Performance Modulation of Printed Two-Dimensional GaO_x Film Transistor Upon Annealing Treatment

Gallium oxide (Ga 2 O 3 ), an emerging ultrabroadband semiconductor, is a crucial material for developing next-generation high-efficiency, high-power electronic devices. In this work, we prepared 2D GaO x films for lap thin-film transistors (TFTs) using tumbling to peel off the oxide layer on the surface of the liquid gallium metal. By treating the 2D GaO x films with different annealing temperatures and changing their internal defect concentrations, we realized the tuning of the films in terms of optical properties, electrical properties, and the performance of GaO x -based TFT devices with channel layer thicknesses of less than 10 nm. After annealing, the films were transformed from amorphous GaO x to β-Ga 2 O 3, the visible transmittance was kept above 98%, the oxygen vacancy concentration decreased from 69 to 9.1%, the figure of merit increased monotonically from 3.9 to 4.2 eV, and the electrical characteristics gradually transitioned from a conductor to a semi-insulator. The I off of GaO x -based TFTs is below 1 nA, and the I on / I off can reach 10 4, showing excellent potential in electrical devices.