【Device Papers】High-performance InGaZnO/Ga₂O₃ heterostructure TFTs Gated by high-k Ta₁.₀La₀.₄O₃.₈ fabricated at room temperature

      Researchers from the Beijing Institute of Technology have published a dissertation titled "High-performance InGaZnO/Ga₂O₃ heterostructure TFTs Gated by high-k Ta_1.0La_0.4O_3.8 fabricated at room temperature" in Applied Surface Science.

Abstract

      High-performance indium-gallium-zinc-oxide (InGaZnO)/gallium oxide (Ga₂O₃) heterostructure thin-film transistors (TFTs) featuring high-k tantalum-lanthanum-oxide (TaLaO) gate dielectric have been successfully fabricated via room-temperature sputtering. As investigated by atomic force microscopy (AFM) and x-ray photoelectron spectroscopy (XPS), the high-k Ta_1.0La_0.4O_3.8 can be effectively smoothened by post-deposition plasma treatments at room temperature, suppressing interfacial defects of oxygen vacancies to improve interfacial quality. Remarkably, the electrical characteristics of the heterostructure TFTs are significantly improved by the O₂-plasma treatment to yield an ultralow subthreshold swing (SS) of 82.1 mV/dec, an ultrahigh on/off ratio (I_ON/I_OFF) of 4.1 × 10¹⁰, and a high field-effect mobility (µ_FE) of 68.0 cm²/V·s. This work presents an innovative method that is effective, ultralow-thermal-budget, and cost-efficient for high-performance heterostructure TFTs with high-k gate dielectrics.

DOI：

https://doi.org/10.1016/j.apsusc.2024.161997