Weighted-Sum Operation of Three-Terminal Synapse Transistors in Array Configuration Using Spin-Coated Li-Doped ZrO Electrolyte Gate Insulator.

Artificial synapses with ideal functionalities are essential in hardware neural networks to allow for energy-efficient analog computing. Electrolyte-gated transistors (EGTs) are promising candidates for artificial synaptic devices due to their low voltage operations supported by large specific capacitances of electrolyte gate insulators (EGIs). We investigated the synapse transistor employing an In-Ga-Zn-O channel and a Li-doped ZrO (LZO) EGI so as to improve the short-term plasticity (STP) and long-term potentiation (LTP).

Carbon dioxide gasification characteristics of disposable COVID-19 masks using bubbling fluidized bed reactor.

The global demand for masks has increased significantly owing to COVID-19 and mutated viruses, resulting in a massive amount of mask waste of approximately 490,000 tons per month. Mask waste recycling is challenging because of the composition of multicomponent polymers and iron, which puts them at risk of viral infection. Conventional treatment methods also cause environmental pollution.

Improvement in current drivability and stability in nanoscale vertical channel thin-film transistors via band-gap engineering in In-Ga-Zn-O bilayer channel configuration.

Vertical channel thin film transistors (VTFTs) have been expected to be exploited as one of the promising three-dimensional devices demanding a higher integration density owing to their structural advantages such as small device footprints. However, the VTFTs have suffered from the back-channel effects induced by the pattering process of vertical sidewalls, which critically deteriorate the device reliability. Therefore, to reduce the detrimental back-channel effects has been one of the most urgent issues for enhancing the device performance of VTFTs.

Hydrogen-rich gas production from disposable COVID-19 mask by steam gasification.

Globally, the demand for masks has increased due to the COVID-19 pandemic, resulting in 490,201 tons of waste masks disposed of per month. Since masks are used in places with a high risk of virus infection, waste masks retain the risk of virus contamination. In this study, a 1 kg/h lab-scale (diameter: 0.

Roles of Oxygen Interstitial Defects in Atomic-Layer Deposited InGaZnO Thin Films with Controlling the Cationic Compositions and Gate-Stack Processes for the Devices with Subμm Channel Lengths.

Roles of oxygen interstitial defects located in the In-Ga-Zn-O (IGZO) thin films prepared by atomic layer deposition were investigated with controlling the cationic compositions and gate-stack process conditions. It was found from the spectroscopic ellipsometry analysis that the excess oxygens increased with increasing the In contents within the IGZO channels. While the device using the IGZO channel with an In/Ga ratio of 0.

Implementation of oxide vertical channel TFTs with sub-150 nm channel length using atomic-layer deposited IGZO active and HfOgate insulator.

We fabricated vertical channel thin film transistors (VTFTs) with a channel length of 130 nm using an ALD In-Ga-Zn-O (IGZO) active channel and high-k HfOgate insulator layers. Solution-processed SiOthin film, which exhibited an etch selectivity as high as 4.2 to drain electrode of indium-tin oxide, was introduced as a spacer material.

Impact of oxide gate electrode for ferroelectric field-effect transistors with metal-ferroelectric-metal-insulator-semiconductor gate stack using undoped HfO thin films prepared by atomic layer deposition.

Ferroelectric field-effect transistors (FETs) with a metal-ferroelectric-metal-insulator-semiconductor (MFMIS) gate stack were fabricated and characterized to elucidate the key process parameters and to optimize the process conditions for guaranteeing nonvolatile memory operations of the device when the undoped HfO was employed as ferroelectric gate insulator. The impacts of top gate (TG) for the MFM part on the memory operations of the MFMIS-FETs were intensively investigated when the TG was chosen as metal Pt or oxide ITO electrode. The ferroelectric memory window of the MFMIS-FETs with ITO/HfO/TiN/SiO/Si gate stack increased to 3.

A semi-automatic cell type annotation method for single-cell RNA sequencing dataset.

Single-cell RNA sequencing (scRNA-seq) has been widely applied to provide insights into the cell-by-cell expression difference in a given bulk sample. Accordingly, numerous analysis methods have been developed. As it involves simultaneous analyses of many cell and genes, efficiency of the methods is crucial.

Ferroelectric Switching in Trilayer AlO/HfZrO/AlO Structure.

Since ferroelectricity has been observed in simple binary oxide material systems, it has attracted great interest in semiconductor research fields such as advanced logic transistors, non-volatile memories, and neuromorphic devices. The location in which the ferroelectric devices are implemented depends on the specific application, so the process constraints required for device fabrication may be different. In this study, we investigate the ferroelectric characteristics of Zr doped HfO layers treated at high temperatures.

PRC2 Acts as a Critical Timer That Drives Oligodendrocyte Fate over Astrocyte Identity by Repressing the Notch Pathway.

PRC2 creates the repressive mark histone H3 Lys27 trimethylation. Although PRC2 is involved in various biological processes, its role in glial development remains ambiguous. Here, we show that PRC2 is required for oligodendrocyte (OL) differentiation and myelination, but not for OL precursor formation.

Comparative studies on vertical-channel charge-trap memory thin-film transistors using In-Ga-Zn-O active channels deposited by sputtering and atomic layer depositions.

Vertical-channel charge-trap memory thin film-transistors (V-CTM TFTs) using oxide semiconductors were fabricated and characterized, in which In-Ga-Zn-O (IGZO) channels were prepared by sputtering and atomic-layer deposition (ALD) methods to elucidate the effects of deposition process. The vertical-channel gate stack of the fabricated device was verified to be well implemented on the vertical sidewall of the spacer patterns due to excellent step-coverage and self-limiting mechanisms of ALD process. The V-CTM TFTs using ALD-IGZO channel exhibited a wide memory window (MW) of 15.

Implementation of an electrically modifiable artificial synapse based on ferroelectric field-effect transistors using Al-doped HfO thin films.

Human brain-like synaptic behaviors of the ferroelectric field-effect transistors (FeFETs) were emulated by introducing the metal-ferroelectric-metal-insulator-semiconductor (MFMIS) gate stacks employing Al-doped HfO2 (Al:HfO2) ferroelectric thin films even at a low operation voltage. The synaptic plasticity of the MFMIS-FETs could be gradually modulated by the partial polarization characteristics of the Al:HfO2 thin films, which were examined to be dependent on the applied pulse conditions. Based on the ferroelectric polarization switching dynamics of the Al:HfO2 thin films, the proposed devices successfully emulate biological synaptic functions, including excitatory post-synaptic current (EPSC), paired-pulse facilitation (PPF), and spike timing-dependent plasticity (STDP).

Impact of Polyimide Film Thickness for Improving the Mechanical Robustness of Stretchable InGaZnO Thin-Film Transistors Prepared on Wavy-Dimensional Elastomer Substrates.

We report on the In-Ga-Zn-O thin-film transistors (IGZO TFTs) with outstanding mechanical stretchability, which were fabricated on ultrathin polyimide (PI) film/prestrained elastomer with a wavy-dimensional structure. The device characteristics of the fabricated devices were evaluated under mechanically strained conditions with various strains. The operational reliabilities against the bias stress conditions and during the cyclic stretching tests were also carefully examined.

Reliability enhancement in thin film transistors using Hf and Al co-incorporated ZnO active channels deposited by atomic-layer-deposition.

Oxide thin films transistors (TFTs) with Hf and Al co-incorporated ZnO active channels prepared by atomic-layer deposition are presented. The Al concentration was fixed at 2.6 at% and the Hf concentration was varied from 3.

Investigations on the bias temperature stabilities of oxide thin film transistors using In-Ga-Zn-O channels prepared by atomic layer deposition.

Bias temperature stress stabilities of thin-film transistors (TFTs) using In-Ga-Zn-O (IGZO) channels prepared by the atomic layer deposition process were investigated with varying channel thicknesses (10 and 6 nm). Even when the IGZO channel thickness was reduced to 6 nm, the device exhibited good characteristics with a high saturation mobility of 15.1 cm V s and low sub-threshold swing of 0.

Nitrogen Doping Effect for Improving Operation Reliability of Phase Modulator Using Ge₂Sb₂Te Thin Film for Hologram Image Implementation.

A phase modulation device was proposed for the implementation of hologram image for display applications. A Ge2Sb2Te5 (GST) film as thin as 7 nm was prepared between the ITO films to form the cavities corresponding a unit pixel. Nitrogen was incorporated into the GST for improving the thermal stability of the GST active region.

Effects of Deposition Temperature on the Device Characteristics of Oxide Thin-Film Transistors Using In-Ga-Zn-O Active Channels Prepared by Atomic-Layer Deposition.

We demonstrated the physical and electrical properties of the In-Ga-Zn-O (IGZO) thin films prepared by atomic-layer deposition (ALD) method and investigated the effects of the ALD temperature. The film composition (atomic ratio of In:Ga:Zn) and film density were examined to be 1:1:3 and 5.9 g/cm, respectively, for all the temperature conditions.

Atomic-layer-deposition-assisted ZnO nanoparticles for oxide charge-trap memory thin-film transistors.

ZnO nanoparticles (NPs) with monolayer structures were prepared by atomic layer deposition (ALD) to use for a charge-trap layer (CTL) for nonvolatile memory thin-film transistors (MTFTs). The optimum ALD temperature of the NP formation was demonstrated to be 160 °C. The size and areal density of the ZnO NPs was estimated to be approximately 33 nm and 4.

Highly Bendable In-Ga-ZnO Thin Film Transistors by Using a Thermally Stable Organic Dielectric Layer.

Flexible In-Ga-ZnO (IGZO) thin film transistor (TFT) on a polyimide substrate is produced by employing a thermally stable SA7 organic material as the multi-functional barrier and dielectric layers. The IGZO channel layer was sputtered at Ar:O gas flow rate of 100:1 sccm and the fabricated TFT exhibited excellent transistor performances with a mobility of 15.67 cm/Vs, a threshold voltage of 6.

Necessity of Surgical Site Closed Suction Drain for Pterional Craniotomy.

Objective: The aim of this study was to assess the benefit of using a prophylactic surgical site closed suction drain in pterional craniotomy.

Materials And Methods: A retrospective review was conducted on 607 consecutive patients who underwent a pterional craniotomy for treatment of intracranial anterior circulation aneurysms over a 5-year period. Between January 2000 and December 2004, 607 patients were divided into two groups, those who had a prophylactic suction drain during closure of the surgical site (drain group, DG) and those who did not (non-drain group, NDG).

Nonvolatile memory thin-film transistors using biodegradable chicken albumen gate insulator and oxide semiconductor channel on eco-friendly paper substrate.

Nonvolatile memory thin-film transistors (TFTs) fabricated on paper substrates were proposed as one of the eco-friendly electronic devices. The gate stack was composed of chicken albumen gate insulator and In-Ga-Zn-O semiconducting channel layers. All the fabrication processes were performed below 120 °C.

Origin of degradation phenomenon under drain bias stress for oxide thin film transistors using IGZO and IGO channel layers.

Top-gate structured thin film transistors (TFTs) using In-Ga-Zn-O (IGZO) and In-Ga-O (IGO) channel compositions were investigated to reveal a feasible origin for degradation phenomenon under drain bias stress (DBS). DBS-driven instability in terms of V(TH) shift, deviation of the SS value, and increase in the on-state current were detected only for the IGZO-TFT, in contrast to the IGO-TFT, which did not demonstrate V(TH) shift. These behaviors were visually confirmed via nanoscale transmission electron microscopy and energy-dispersive x-ray spectroscopy observations.

Surgical extrusion of multiple teeth with crown-root fractures: a case report with 18-months follow up.

The objective of this case report is to describe the treatment procedure involved in surgical extrusion of multiple crown-root fractures and review the critical factors to be considered for successful and predictable outcome. The treatment of complicated crown-root fracture in anterior teeth is likely to compromise function and aesthetics when approached with conventional surgical crown lengthening. Orthodontic extrusion has also been suggested; however, it is time-consuming, aesthetically compromising and hardly applicable on multiple anterior crown-root fractures due to the limited source of anchorage.

Effect of the electrode materials on the drain-bias stress instabilities of In-Ga-Zn-O thin-film transistors.

The effects of electrode materials on the device stabilities of In-Ga-Zn-O (IGZO) thin-film transistors (TFTs) were investigated under gate- and/or drain-bias stress conditions. The fabricated IGZO TFTs with a top-gate bottom-contact structure exhibited very similar transfer characteristics between the devices using indium-tin oxide (ITO) and titanium electrodes. Typical values of the mobility and threshold voltage of each device were obtained as 13.

Antimony selenide phase-change nanowires for memory application.

Synthesis and device characteristics of highly scalable antimony selenide nanowire-based phase transition memory are reported. Antimony selenide nanowires prepared using the metal-catalyst-free approach are single-crystalline and of high-purity. The nanowire memory can be repeatedly switched between high-resistance (approximately 10 Momega) and low-resistance (approximately 1 komega) states which are attributed to amorphous and crystalline states, respectively.