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Amorphous IGZO (a‐IGZO) thin‐film transistors (TFTs) are standard backplane electronics to power active‐matrix organic light‐emitting diode (AMOLED) televisions due to their high carrier mobility and negligible low leakage characteristics. Despite their advantages, limitations in color depth arise from a steep subthreshold swing (SS) (≤ 0.1 V/decade), necessitating costly external compensation for IGZO transistors. For mid‐size mobile applications such as OLED tablets and notebooks, it is important to ensure controllable SS value (≥ 0.3 V/decade). In this study, a conversion mechanism during plasma‐enhanced atomic layer deposition (PEALD) is proposed as a feasible route to control the SS. When a pulse of a diethylzinc (DEZn) precursor is exposed to the M2O3 (M = In or Ga) surface layer, partial conversion of the underlying M2O3 to ZnO is predicted on the basis of density function theory calculations. Notably, significant distinctions between In‐Ga‐Zn (Case I) and In‐Zn‐Ga (Case II) films are observed: Case II exhibits a lower growth rate and larger Ga/In ratio. Case II TFTs with a‐IGZO (subcycle ratio of In:Ga:Zn = 3:1:1) show reasonable SS values (313 mV decade−1) and high mobility (µFE) of 29.3 cm2 Vs−1 (Case I: 84 mV decade−1 and 33.4 cm2 Vs−1). The rationale for Case II's reasonable SS values is discussed, attributing it to the plausible formation of In‐Zn defects, supported by technology computer‐aided design (TCAD) simulations. [ABSTRACT FROM AUTHOR]

Electrocatalytic water splitting is crucial to generate clean hydrogen fuel, but implementation at an industrial scale remains limited due to dependence on expensive platinum (Pt)-based electrocatalysts. Here, an all-dry process to transform electrochemically inert bulk WS 2 into a multidomain electrochemical catalyst that enables scalable and cost-effective implementation of the hydrogen evolution reaction (HER) in water electrolysis is reported. Direct dry transfer of WS 2 flakes to a gold thin film deposited on a silicon substrate provides a general platform to produce the working electrodes for HER with tunable charge transfer resistance. By treating the mechanically exfoliated WS 2 with sequential Ar-O 2 plasma, mixed domains of WS 2 , WO 3 , and tungsten oxysulfide form on the surfaces of the flakes, which gives rise to a superior HER with much greater long-term stability and steady-state activity compared to Pt. Using density functional theory, ultraefficient atomic sites formed on the constituent nanodomains are identified, and the quantification of atomic-scale reactivities and resulting HER activities fully support the experimental observations., (© 2024 The Authors. Advanced Materials published by Wiley‐VCH GmbH.)

Indium oxide (In 2 O 3 ) is a transparent wide-bandgap semiconductor suitable for use in the back-end-of-line-compatible channel layers of heterogeneous monolithic three-dimensional (M3D) devices. The structural, chemical, and electrical properties of In 2 O 3 films deposited by plasma-enhanced atomic layer deposition (PEALD) were examined using two different liquid-based precursors: (3-(dimethylamino)propyl)-dimethyl indium (DADI) and ( N , N -dimethylbutylamine)trimethylindium (DATI). DATI-derived In 2 O 3 films had higher growth per cycle (GPC), superior crystallinity, and low defect density compared with DADI-derived In 2 O 3 films. Density functional theory calculations revealed that the structure of DATI can exhibit less steric hindrance compared with that of DADI, explaining the superior physical and electrical properties of the DATI-derived In 2 O 3 film. DATI-derived In 2 O 3 field-effect transistors (FETs) exhibited unprecedented performance, showcasing a high field-effect mobility of 115.8 cm 2 /(V s), a threshold voltage of -0.12 V, and a low subthreshold gate swing value of <70 mV/decade. These results were achieved by employing a 10-nm-thick HfO 2 gate dielectric layer with an effective oxide thickness of 3.9 nm. Both DADI and DATI-derived In 2 O 3 FET devices exhibited remarkable stability under bias stress conditions due to a high-quality In 2 O 3 channel layer, good gate dielectric/channel interface matching, and a suitable passivation layer. These findings underscore the potential of ALD In 2 O 3 films as promising materials for upper-layer channels in the next generation of M3D devices.