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In this article, this research demonstrates the influence of in-situ introduction of H2 into the working gas on the physical properties of post-annealed In2O3 thin films and the performance of associated devices. A gradual increase in the H2 ratio leads to improved film quality, as indicated by spectroscopic ellipsometry, X-ray photoelectron spectroscopy, and atomic force microscope analyses showing a reduction in defect states such as band-tail states and VO in the film, and a smoother surface morphology with the root mean square roughness approximately 0.446 nm. Furthermore, this hydrogen doping effect results in a distinct shift in the device's threshold voltage toward the positive direction, and an improvement in the field-effect mobility and subthreshold swing. Consequently, a high-performance In2O3:H TFT is developed, exhibiting a field-effect mobility of 47.8 cm2/Vs, threshold voltage of −4.1 V and subthreshold swing of 0.25 V/dec. These findings highlight the potential of in-situ H doping as a promising approach to regulate In2O3-based TFTs. [ABSTRACT FROM AUTHOR]

The exploration of bionic neuromorphic chips, capable of processing sensory data in a human‐like manner, is both a trend and a challenge. There is a strong demand for phototransistors that offer broadband in‐sensor adaptability. This study introduces a bioinspired vision sensor based on InP quantum dots (QDs)/InSnZnO hybrid phototransistors. This novel design combines the excellent electrical transportation features of oxide semiconductors with the superior optoelectronic response of InP QDs. The resulting hybrid devices exhibit exceptional gate controllability and a robust visible‐light response. These characteristics enable the emulation of multiple functions of the human visual system and the accommodation of varying light intensity environments. Furthermore, the phototransistor array successfully replicates the scotopic and photopic adaptation recognition behaviors of the human retina. Notably, the device demonstrates faultless competency in image processing, achieving an impressive 93% accuracy for digit recognition. These findings contribute to the advancement of bionic neuromorphic chips and offer promising opportunities for future developments in the bioinspired visual system. [ABSTRACT FROM AUTHOR]

Amorphous gallium oxide (a-GaO x) thin films are fabricated via magnetron sputtering at room temperature by regulating the substrate bias voltage (V s) in a wide range (0 ~ -184 V). The effect of V s on the performance of a-GaO x films and their photodetector devices, such as the chemical composition, optical, morphological, and electrical properties, are systematically investigated. It's found that both the refractive index and the film relative mass density are highly dependent on the Ga/O ratio that can be effectively modified by the V s. And the subband trap density or/and microvoid defects in a-GaO x films can be largely reduced under a well-selected V s. The deep-ultraviolet photodetectors based on the optimized a-GaO x thin films show a responsivity of nearly 13 A/W with an ultrahigh UV/vis. rejection ratio. The research suggests that substrate bias voltage may be a feasibly subsidiary method for low-temperature magnetron sputtering technology with respect to the quality control of a-GaO x films. [ABSTRACT FROM AUTHOR]

P-type Cu-Sn-I thin films with different Sn contents (CSn) were fabricated in air via a simple and low-cost spin-coating method. Sn additive facilitates the amorphization of CuI, and a complete amorphous phase of Cu-Sn-I film is achieved at CSn =15%. With increasing CSn, the optical bandgap increases and refractive index decreases, probably due to the influence of Sn-additive on both the electronic structure and phase state of the films. The air-processed Sn-free CuI films show p-type conduction with hole mobility and a concentration of 17.3 cm2/V−1 s−1 and 1.1 × 1019 cm−3, and an increasing trend of resistivity is observed along with a large drop in hole concentration during the Sn-inspired amorphization process. Moreover, transparent Cu-Sn-I/IGZO p–n junctions were constructed, exhibiting the optimum rectifying characteristic at CSn = 15% with a forward-to-reverse ratio of 6.2 × 103. [ABSTRACT FROM AUTHOR]

Concerning the revolutionary future of electronic devices, high-performance solution-processable semiconductors have earned increasing academic and industrial research interests. In this paper, we synthesize In-Ga-Cd-O semiconductor thin films via a solution method. Transparent amorphous/nanocrystalline oxide thin films with small surface roughness have been grown by controlling the relative ratio of Cd-content. The present thin-film transistor with an optimized Cd-ratio exhibits a saturation field-effect mobility up to 10 cm² V-1 s-1, an on/off current ratio of ≈1.3×109, and a threshold voltage shift of ≈2.6 V under -5 V gate bias of 10 000 s, which are superior or comparable to those reported values of solution-processed conventional In-Ga-Zn-O counterparts. Our results indicate that the proposed In-Ga-Cd-O semiconductor would endow a promising transparent amorphous/nanocrystalline active material for electronic devices. [ABSTRACT FROM AUTHOR]

In this article, we report the growth of zinc‐tin nitride (ZnSnN2) thin films as a potential absorber for photovoltaic applications by fabricating a heterojunction of n‐ZnSnN2/p‐SnO. The performance of the heterojunction has been monitored through selective deposition of top electrode with different materials (Ni/Au or Al). The electron‐transfer process from the ZnSnN2 layer to the cathode is facilitated by selecting metal electrode with relatively low work function, which also boosts up the electron injection or/and extraction. The diode exhibits a good J–V response in the dark with a rectification ratio of 3 × 103 at 1.0 V and an ideality factor of 4.2 in particular with Al as the top electrode. Under illumination, the heterostructure solar cell demonstrates a power conversion efficiency of ≈0.37% with an open circuit voltage of 0.25 V and a short circuit current density of 4.16 mA cm−2. The prime strategies, on how to improve solar cell efficiency concerning band offsets and band alignment engineering are also discussed. [ABSTRACT FROM AUTHOR]

Today, the earnest need for earth-abundant and environmentally friendly thermoelectric materials has revealed the importance of semiconductor metal oxides in order to eliminate the barrier towards their wide-ranging use in industrial applications. In the present work, we demonstrate the synthesis of p-type tin oxide thin films on quartz glass and Si substrates by using electron beam evaporation technique followed by rapid thermal annealing process at 200 °C for 20 min in Ar-atmosphere. Annealing-induced structural, electrical, optical and thermoelectric properties of pristine and annealed SnO thin films are primarily studied. The compositional and structural analysis of SnO films are performed by using X-Ray Diffraction, Scanning Electron Microscope as well as Atomic Force Microscope. Moreover, the mechanism of thermoelectric transportation at different measurement temperatures is deeply inspected via thermoelectric measurements. The Seebeck coefficient, carrier concentration and hole mobility in conjunction with the development of thin film nanostructures are discussed, predominantly. The optimal annealing may tune structural, electro-optic and thermoelectric properties of SnO films for the commercial-level maturity of thermoelectric devices for energy applications. • Synthesis of high quality p-type SnO thin films by e-beam evaporation method. • Phase stability can be achieved by optimal annealing of tin oxide thin films. • Electrical resistivity and mobility affects the thermoelectric properties. • Optimal annealing reduces the crystal imperfections and band-tail states in SnO films. • The air-annealing induces the phase transition in SnO x thin films. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of high quality p-type SnO thin films by e-beam evaporation method. • Post deposition heat treatment of SnO x films at temperature (300–700 °C). • Optimal annealing reduces the crystal imperfections and band-tail states in SnO films. • Study of temperature-dependent morphology evolution for preferred crystal growth. In the present work, we demonstrate the growth of tin oxide (SnO x) thin films using electron beam evaporation method to study the phase transition from stannous oxide (SnO) to stannic oxide (SnO 2) by varying annealing temperature (i.e., from 300 to 700 °C). Annealing induced morphology evolution and structural modifications stimulate the process of phase-transformation, which is primarily discussed by divided the entire temperature range into two-regimes. Regime-A (from 300 to 400 °C) consists of tetragonal α-SnO dominated phase, regime-B (from 600 to 700 °C) exhibits orthorhombic pure SnO 2 phase. However, these regimes are being separated by an interface conferring a mixed-phase of tin oxides at an annealing temperature ∼500 °C. This temperature-dependent phase-inversion is adequately controlled by tuning the morphological, structural and optical properties of SnO x thin films to develop homo/heterostructures for various photovoltaic and optoelectronic applications. [ABSTRACT FROM AUTHOR]

Abstract: An amorphous carbon thin film, with through-pores of several tens of nanometers in size, has been synthesized by annealing magnetron sputtered nitrogen-doped carbon thin films at elevated temperature in an inert atmosphere. Based on this nanoporous carbon film, we first report forming-free resistive switching in a two terminal device containing ready-made metal nanofilaments. Such nanoporous carbon-based resistance memory device shows low operation voltages and good endurance and retention performance. [Copyright &y& Elsevier]