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In this paper, high-performance indium gallium oxide (IGO) thin-film transistor (TFT) with a double-gate (DG) structure was developed using an atomic layer deposition route. The device consisting of 10-nm-thick IGO channel and 2/48-nm-thick SiO2/HfO2 dielectric was designed to be suitable for a display backplane in augmented and virtual reality applications. The fabricated DG TFTs exhibit outstanding device performances with field-effect mobility (μFE) of 65.1 ± 2.3 cm2V−1 s−1, subthreshold swing of 65 ± 1 mVdec−1, and threshold voltage (VTH) of 0.42 ± 0.05 V. Both the (μFE) and SS are considerably improved by more than two-fold in the DG IGO TFTs compared to single-gate (SG) IGO TFTs. Important finding was that the DG mode of IGO TFTs exhibits the nearly temperature independent μFE variations in contrast to the SG mode which suffers from the severe remote Coulomb scattering. The rationale for this disparity is discussed in detail based on the potential distribution along the vertical direction using technology computer-aided design simulation. Furthermore, the DG IGO TFTs exhibit a greatly improved reliability with negligible VTH shift of − 0.22 V under a harsh negative bias thermal and illumination stress condition with an electric field of − 2 MVcm−1 and blue light illumination at 80 °C for 3600 s. It could be attributed to the increased electrostatic potential that results in fast re-trapping of the electrons generated by the light-induced ionization of deep level oxygen vacancy defects. [ABSTRACT FROM AUTHOR]

The high‐performance amorphous In‐Ga‐Sn‐O (a‐IGTO) thin‐film transistors (TFTs) was fabricated with plasma‐enhanced atomic layer deposition (PEALD)‐derived Al2O3 high‐k gate dielectric at a maximum processing temperature of 150 °C. During the deposition of Al2O3 dielectric on a‐IGTO films, the hydrogen (H) and excess oxygen (Oi) defects from the Al2O3 act significant role on TFTs operation. The amounts of H and Oi can be controlled by adjusting oxygen plasma density in radio‐frequency (rf) of PEALD. The optimized a‐IGTO TFT exhibit high‐performance electrical properties with field‐effect mobility (μFE) of 58.8 cm2/Vs, subthreshold gate swing (SS) of 0.12 V/decade, threshold voltage (VTH) of 0.5 V. [ABSTRACT FROM AUTHOR]

In this study, we examine the effect of oxygen vacancies (${V}_{O}$) near the back surface of p-type tin monoxide (SnO) semiconductors on the device performance of its thin-film transistors (TFTs). Non-stoichiometry of the SnO surface layer was controlled through oxidant exposure conditions during alumina (Al2O3) growth using plasma-enhanced atomic layer deposition (PEALD). During the initial period of Al2O3 deposition, trimethylaluminum precursors absorbed oxygen from the SnO layer and created the ${V}_{O}$ , which can form a ${V}_{O}$ -rich region at the Al2O3/SnO interface. By modulating the oxygen plasma density during the PEALD process, the ${V}_{O}$ was effectively controlled, allowing the electrical characteristics to transition from ambipolar behavior to ${p}$ -channel only conduction. This study demonstrates the importance of the back surface of SnO, suggesting a new perspective of ambipolar behavior in p-type SnO semiconductors. [ABSTRACT FROM AUTHOR]