Monoclinic gallium oxide (β-Ga2O3) has attracted the interest of the scientific community due to its application in power electronics. Power electronics that need to handle a high voltage often uses a “normally off” device with a positive threshold voltage due to its fail-safe operation and its simple system architecture. In this work, 8-nm-thick Sn-doped polycrystalline β-Ga2O3 thin films were investigated as a channel material for power electronics, and their properties were characterized. The optical bandgap of the 8-nm-thick Sn-doped β-Ga2O3 was determined to be 5.77 eV, which is larger than that of 100-nm-thick Sn-doped β-Ga2O3 due to the quantum confinement effect. The developed back-gated device demonstrated normally off behavior and exhibited a voltage handling capacity as high as 224 V (2.88 MV/cm). This ultrathin β-Ga2O3 layer could also be applied to fields other than power electronics, including displays, optical sensors, photocatalytic sensors, and solar cells.

Hybrid organic‐inorganic polymeric films are widely used in various areas, for encapsulation, dielectrics, super‐hydrophobic surfaces, membranes, and other applications, because of the features of their organic and inorganic components. The initiated chemical vapor deposition (iCVD) process is developed to synthesize hybrid polymeric films via this approach. However, the conventional iCVD process is based on laminar injection, and has difficulty depositing hybrid films with uniform thickness and composition over the large areas required by industry. In this work, the geometry of the iCVD chamber is newly designed to enable conformal and uniform deposition over an 8‐inch area, using a dual showerhead structure injection system. The inorganic concentration and deposition rate can be linearly controlled by adjusting the flow ratio of the inorganic precursor and organic monomer, up to 25% and 2.75 nm min−1, respectively. In addition, the dual showerhead injector reduces the source consumption by 37%, compared to a conventional laminar flow iCVD chamber, while depositing a film with the same thickness and composition. The surface roughness of the entire 8‐inch area is less than 0.6 nm, showing that very uniform and homogeneous hybrid polymeric films can be successfully synthesized over a large area. In addition, the variation in electrical capacitance between metal–insulator–metal (MIM) structure devices is measured, and is within 4.1% over the entire wafer for films deposited with the dual showerhead chamber, compared with 30% for the conventional iCVD chamber. The iCVD process with the dual showerhead structure enables the synthesis of conformal and uniform hybrid polymeric films over a large‐scale area with lower source consumption, compared to conventional iCVD.

and long-term retention characteristics, have increased continually. To meet those requirements, there have been studies about various combination of materials and electrodes, as well as their conducting filament (CF) behavior and formation mechanism in ReRAM.The formation mechanisms of the CF in ReRAM have been classified into valence change mechanism of oxygen vacancy generation (VCM) and electrochemical mechanism of metal ion migration (ECM). [2,3] VCM usually occurs in oxide-based ReRAM and relies on the conductive channels formed by the arrangement of the oxygen vacancies. The performance of oxide-based ReRAM depends on the combination of the oxide layer and the electrode and have been reported to show highly reliable characteristics. [4,5] Organic materials have been studied as prospective materials to realize ECM ReRAM devices, [6,7] and in particular polymers have exhibited information storage capability due to their ability to conduct and switch currents. [8] Furthermore, the functionalities of polymers can be tuned as needed to assist formation of metallic filament in the polymer matrix. [9][10][11] As opposed to VCM, ECM-based ReRAM shows lower reliability with a very large on/off ratio (>10 4 ), suitable to be used as a selector. [6,12] To take advantage in both organic and inorganic compound, perovskite materials have been studied and developed as active layer in ReRAM, and they have shown notable resistive memory performance. [13][14][15][16][17] The perovskite materials have advantages in their excellent charge mobility, low temperature process for simplifying the process, and cost-effectiveness of large-scale area. [16] In addition, perovskite materials have interesting functionalities, such as dielectric, ferroelectric, semiconducting, and light-sensitivity. [13,18] Furthermore, optoelectronic-based perovskite ReRAM devices have been introduced and studied as a neuromorphic device. [15,19] These advances have led to the incorporation of ECM and VCM in the active matrix to enable synergy in resistive switching behavior in ReRAM. [14] In this study, the active layer of the ReRAM device is chosen as organic-inorganic hybrid materials prepared by initiated chemical vapor deposition (iCVD) process which enables the synthesis of pure ultra-thin polymeric films without solvent. [20][21][22] The iCVD process offers the following advantages over perovskite processes: a room temperature process, [23] ultra-thin film Resistive random-access memory (ReRAM) has been considered for future memory devices, because of its low-power consumption and a high degree of integration. In this study, hybrid (H-) ReRAM devices are proposed using ultra-thin (<10 nm) Al, Hf, and Zr hybrid films prepared via initiated chemical vapor deposition (iCVD). The hybrid films homogeneously consist of organic and inorganic components, which allow simultaneous metal atoms migration and oxygen vacancy generation. Regardless of hybrid matrix, H-ReRAMs show highly reliable performance results (on/off ratio >10 4 , endurance >10 6 , retent...

To achieve the low power operation required by various high performance flexible electronics, such as switching and memory devices, advanced gate dielectrics should be ultra‐thin, flexible, with low gate leakage current. Organic–inorganic hybrid dielectrics are proposed to realize this combination of attributes, where the organic matrix contributes outstanding mechanical flexibility and the inorganic component provides the required electrical characteristics. Among candidate inorganic components, HfOx and TiOx are particularly attractive because of their high dielectric constant (high‐k) and wide/narrow energy bandgap. Flexible Hf and Ti hybrid high‐k dielectrics are synthesized in this work via an initiated chemical vapor deposition (iCVD) process, where 2‐hydroxyethyl‐methacrylate (HEMA) and tert‐butyl peroxide (TBPO) are used as monomers and initiators, respectively. The synthesized Hf hybrid dielectrics exhibit a high‐k value of 9.6, leakage currents below 1.0 × 10–6 A cm–2 at 2 MV cm–1, bandgaps of 5.9 eV, and electrical breakdown fields over 3 MV cm–1. The synthesized Ti hybrid dielectrics exhibit the highest k‐value of 13.0 and decent currents below 1.0 × 10–4 A cm–2 at 2 MV cm–1 due to its narrow bandgap of 3.8 eV, making it suitable for use as a charge trapping layer for flexible memory devices, rather than as a gate dielectric. n‐type and p‐type organic thin film transistors (OTFT) prepared with the Hf hybrid dielectrics exhibit typical transfer and output characteristics, even under tensile stresses as high as 2.0% strain. Under the mechanical stress condition of 2.0% tensile strain, no noticeable degradation is observed in the Hf hybrids in terms of saturation mobility (μsat), subthreshold swing (S.S.), interface trap density (Dit), threshold voltage (VT), or hysteresis. These results show that the Hf and Ti hybrid dielectrics can enhance the performance of flexible electronics.

This research study thoroughly examines the optimal thickness of indium tin oxide (ITO), a transparent electrode, for near-ultraviolet (NUV) light-emitting diodes (LEDs) based on InGaN/AlGaInN materials. A range of ITO thicknesses from 30 to 170 nm is investigated, and annealing processes are performed to determine the most favorable figure of merit (FOM) by balancing transmittance and sheet resistance in the NUV region. Among the films of different thicknesses, an ITO film measuring 110 nm, annealed at 550 °C for 1 min, demonstrates the highest FOM. This film exhibits notable characteristics, including 89.0% transmittance at 385 nm, a sheet resistance of 131 Ω/□, and a contact resistance of 3.1 × 10−3 Ω·cm2. Comparing the performance of NUV LEDs using ITO films of various thicknesses (30, 50, 70, 90, 130, 150, and 170 nm), it is observed that the NUV LED employing ITO with a thickness of 110 nm achieves a maximum 48% increase in light output power at 50 mA while maintaining the same forward voltage at 20 mA.