High-Performance Atomic-Layer-Deposited Dual-Gate InGaO Thin-Film Transistors

Amorphous oxide semiconductors (AOSs) have attracted considerable attention because of their high carrier density, low thermal budget, and large bandgap. However, the high electron density in AOSs hinders their ability to turn off effectively, resulting in a trade-off between the threshold voltage (<i>V</i>_th) and mobility (μ). In this work, we report high-performance dual-gate (DG) indium gallium oxide (IGO) TFTs utilizing localized O₃ treatment to effectively passivate the oxygen vacancies (V_o) in the channel region of IGO TFTs, thereby achieving a positive <i>V</i>_th and high mobility. The 100 nm short-channel length (<i>L</i>_ch) enhancement-mode IGO DG TFT exhibits an ideal subthreshold slope (SS) of 63 mV/dec, a maximum drain current <i>I</i>_DS of 1.36 mA/μm, and a record high transconductance (<i>g</i>_m) of 1008 μS/μm. This study demonstrates a novel method to overcome the trade-off between <i>V</i>_th and μ, showing that IGO DG-TFTs are promising transistors for enabling high-performance monolithic three-dimensional (M3D) integrated circuits.