Explore the vast range of titles available.

One factor that is considered to be a cause of global boiling, which is becoming a serious social problem, is the rapid progress and widespread use of artificial intelligence (AI). We focus on an oxide ceramic with an extremely low off‐state current (Ioff) of 1 zA/µm to 1 yA/µm and a very large on/off ratio of 17 digits, and we aim to achieve AI with an ultra‐low power consumption using the large‐scale integration of oxide semiconductors (OSs). Field effect transistors (FETs) that include crystal indium oxide (IO) as a channel material exhibit an off‐state current (Ioff) equivalent to that of the FETs that contain indium gallium zinc oxide (IGZO) and an on‐state current (Ion) that is higher than that of the FETs that contain IGZO. Single crystal IO is shown to be a promising material for improving performance and reducing the variation in the characteristics of OS devices. This report introduces the latest trends in the use of oxide ceramics. We expect that the development of these technologies will achieve AI with ultra‐low power consumption in the future, which will be an important remediation against global boiling. The use of oxide ceramic can provide FETs with an extremely low off‐state current of 1 zA/µm to 1 yA/µm and a very large on/off ratio of 17 digits. This report introduces the latest trends in FETs, LSI, and displays using oxide ceramic.

High-voltage GaN switches can offer tremendous advantages over silicon counterparts for the development of high-efficiency switching-mode power converters at high commutation frequency. Nonetheless, GaN devices are prone to charge-trapping effects that can be particularly relevant in the early-stage development of new technologies. Charge-trapping mechanisms are responsible for the degradation of the dynamic ON-resistance (R[sub.ON] ) with respect to its static value: this degradation is typically dependent on the blocking voltage, the commutation frequency and temperature, and is responsible for the reduction of power converter efficiency. The characterization of this phenomenon is very valuable for the development of a new process to compare different technological solutions or for the final assessment of performance. This characterization cannot be made with traditional static or small signal measurements since R[sub.ON] degradation is triggered by application-like dynamic device excitations. In this paper, we propose a technique for the characterization of the dynamic R[sub.ON] of high-voltage GaN switches under real operating conditions: this technique is based on the design of a half bridge switching leg in which the DUT is operated under conditions that resemble its operation in a power converter. With this setup, the characterization of a 600 V GaN switch dynamic R[sub.ON] is performed as a function of variable blocking voltages and commutation frequency. Additionally, this technique allows the separation of thermal and trapping effects, enabling the characterization of the dynamic R[sub.ON] at different temperatures.

In 2009, a crystalline oxide semiconductor with a layered structure, which we refer to as c‐axis–aligned crystalline indium‐gallium‐zinc oxide (CAAC‐IGZO), was first discovered. CAAC‐IGZO has a peculiar crystal structure in which clear grain boundaries are not observed despite high c‐axis alignment and absence of a‐b plane alignment. When compared to a Si field‐effect transistor (FET), a metal‐oxide‐semiconductor (MOS) FET, utilizing CAAC‐IGZO, presents lower off‐state current (on the order of yA [10−24 A]). These unique characteristics allow CAAC‐IGZO to realize devices with low power consumption. With the emerging era of artificial intelligence, wherein power saving becomes more significant, CAAC‐IGZO has attracted attention as a potential replacement for Si. This paper describes the characteristics and potentials of CAAC‐IGZO for the development of memory devices with unprecedented functions. In 2009, we discovered a crystalline oxide semiconductor with a layered structure, which we refer to as c‐axis–aligned crystalline indium‐gallium‐zinc oxide (CAAC‐IGZO). A CAAC‐IGZO FET has an extremely low off‐state current and thus realizes devices with low power consumption. With the emerging era of artificial intelligence, wherein power saving becomes more significant, CAAC‐IGZO has attracted attention as a potential replacement for Si.

The present work reports on the calculated electronic and magnetic structure of the binary Co-Ga system at high Co content. β-CoGa adopts a simple cubic CsCl type structure. Well-ordered CoGa does not exhibit collective magnetism but is a paramagnetic, metallic compound. Neither Co nor Ga deficiency induces magnetic order; however, ferromagnetism is observed for Co-Ga anti-site disorder. The magnetic moment per cell increases by up to approximately 1.2 μ[sub.B] in the completely disordered body-centered cubic structure. With increasing Co content, Co[sub.1+x] Ga[sub.1−x] maintains the CsCl type structure and becomes ferromagnetic. Most importantly, a discontinuity of the magnetic order with composition is observed at about 10% excess Co, where a change from a low magnetic moment state to a high moment state is observed. This is accompanied by a change in the electronic structure and transport properties. The discontinuity is forced by the increasing exchange splitting related to the localized moment of the additional Co atoms that replace Ga. Subsequently, the magnetic moment increases continuously up to 2.5 μ[sub.B] for x=0.6. For x≳0.6, the structure changes to a face-centered cubic structure with random site occupation and the magnetic moment further increases. Above the magnetic discontinuity, the Curie temperature increases linearly with the Co content from the onset of ferromagnetism, until it reaches its maximum in pure Co.

This study investigates the effect of titanium nitride (TiN) interlayers on the performance of ruthenium (Ru)‐based Schottky diodes on N‐polar GaN. The Ru Schottky diodes exhibited the highest mean Schottky barrier height of 0.69 ± $\\pm$0.03 eV; however, they demonstrated a lack of uniformity in barrier height across varying device sizes. Introducing 2 and 10 nm TiN interlayers between Ru and GaN led to consistent Schottky barrier heights and leakage characteristics for all device sizes. Notably, the 2 nm TiN/40 nm Ru configuration achieved an optimal balance between the low leakage current and uniform barrier properties, highlighting the role of TiN in obtaining desirable Schottky barrier performance. 40 nm ALD Ru Schottky diodes show non‐uniform barrier height across devices. However, with a TiN interlayer between the Ru and N‐polar GaN, the Schottky barrier height is uniform across device sizes.

We report large‐signal linearity and power‐added‐efficiency of high‐speed graded‐channel GaN‐based high‐electron‐mobility transistors (HEMTs) at 30 GHz under 64‐QAM and 256‐QAM. These graded‐channel GaN high‐electron‐mobility transistors show an fT of 160 GHz and exhibit a peak power‐added efficiency of 63% at 30 GHz. Under 64‐QAM and 256‐QAM, the error vector magnitude of less than 5% was measured at the average output power of 16 dBm, about 3 dB backed off from the output power at peak power‐added efficiency. We report large‐signal linearity and power‐added‐efficiency of high‐speed graded‐channel GaN‐based high‐electron‐mobility transistors at 30 GHz under 64‐QAM and 256‐QAM. These graded‐channel GaN high‐electron‐mobility transistors show an fT of 160 GHz and peak power‐added efficiency of 6% at 30 GHz. Under 64‐QAM and 256‐QAM, the error vector magnitude of less than 5% was measured at an average output power of 16 dBm, about 3 dB backed off from the output power at peak power‐added efficiency.

In the application of WS[sub.2] as a surface–enhanced Raman scattering (SERS) substrate, enhancing the charge transfer (CT) opportunity between WS[sub.2] and analyte is an important issue for SERS efficiency. In this study, we deposited few-layer WS[sub.2] (2–3 layers) on GaN and sapphire substrates with different bandgap characteristics to form heterojunctions using a chemical vapor deposition. Compared with sapphire, we found that using GaN as a substrate for WS[sub.2] can effectively enhance the SERS signal, with an enhancement factor of 6.45 × 10[sup.4] and a limit of detection of 5 × 10[sup.−6] M for probe molecule Rhodamine 6G according to SERS measurement. Analysis of Raman, Raman mapping, atomic force microscopy, and SERS mechanism revealed that The SERS efficiency increased despite the lower quality of the WS[sub.2] films on GaN compared to those on sapphire, as a result of the increased number of transition pathways present in the interface between WS[sub.2] and GaN. These carrier transition pathways could increase the opportunity for CT, thus enhancing the SERS signal. The WS[sub.2] /GaN heterostructure proposed in this study can serve as a reference for enhancing SERS efficiency.

Nano-ridge engineering (NRE) is a novel heteroepitaxial approach for the monolithic integration of lattice-mismatched III-V devices on Si substrates. It has been successfully applied to GaAs for the realization of nano-ridge (NR) laser diodes and heterojunction bipolar transistors on 300 mm Si wafers. In this report we extend NRE to GaSb for the integration of narrow bandgap heterostructures on Si. GaSb is deposited by selective area growth in narrow oxide trenches fabricated on 300 mm Si substrates to reduce the defect density by aspect ratio trapping. The GaSb growth is continued and the NR shape on top of the oxide pattern is manipulated via NRE to achieve a broad (001) NR surface. The impact of different seed layers (GaAs and InAs) on the threading dislocation and planar defect densities in the GaSb NRs is investigated as a function of trench width by using transmission electron microscopy (TEM) as well as electron channeling contrast imaging (ECCI), which provides significantly better defect statistics in comparison to TEM only. An InAs/GaSb multi-layer heterostructure is added on top of an optimized NR structure. The high crystal quality and low defect density emphasize the potential of this monolithic integration approach for infrared optoelectronic devices on 300 mm Si substrates.

In this work, the radiation response of bulk GaN and Ga[sub.2] O[sub.3] materials exposed to ground-level neutrons is studied by Geant4 numerical simulation, considering the whole atmospheric neutron spectrum at sea level, from thermal to high energies (GeV). The response of the two materials is compared in terms of the number and type of interactions and the nature of the secondary products produced, particularly in nuclear reactions. Our results highlight the importance of [sup.14] N(n,p)[sup.14] C neutron capture in the radiation response of GaN, leading to large differences in the behavior of the two materials in terms of susceptibility to thermal and intermediate-energy (below 1 MeV) neutrons.

ESKAPE bacteria are a major cause of multidrug-resistant infections, and new drugs are urgently needed to combat these pathogens. Given the importance of iron in bacterial physiology and pathogenicity, iron uptake and metabolism have become attractive targets for the development of new antibacterial drugs. In this scenario, the FDA-approved iron mimetic metal Gallium [Ga(III)] has been successfully repurposed as an antimicrobial drug. Ga(III) disrupts ferric iron-dependent metabolic pathways, thereby inhibiting microbial growth. This work provides the first comparative assessment of the antibacterial activity of Ga(NO ) (GaN), Ga(III)-maltolate (GaM), and Ga(III)-protoporphyrin IX (GaPPIX), belonging to the first-, second- and third-generation of Ga(III) formulations, respectively, on ESKAPE species, including reference strains and multidrug-resistant (MDR) clinical isolates. In addition to the standard culture medium Mueller Hinton broth (MHB), iron-depleted MHB (DMHB) and RPMI-1640 supplemented with 10% human serum (HS) (RPMI-HS) were also included in Ga(III)-susceptibility tests, because of their different nutrient and iron contents. All ESKAPE species were resistant to all Ga(III) compounds in MHB and DMHB (MIC > 32 μM), except and , which were susceptible to GaPPIX. Conversely, the antibacterial activity of GaN and GaM was very evident in RPMI-HS, in which the low iron content and the presence of HS better mimic the environment. In RPMI-HS about 50% of the strains were sensitive (MIC < 32) to GaN and GaM, both compounds showing a similar spectrum of activity, although GaM was more effective than GaN. In contrast, GaPPIX lost its antibacterial activity in RPMI-HS likely due to the presence of albumin, which binds GaPPIX and counteracts its inhibitory effect. We also demonstrated that the presence of multiple heme-uptake systems strongly influences GaPPIX susceptibility in . Interestingly, GaN and GaM showed only a bacteriostatic effect, whereas GaPPIX exerted a bactericidal activity on susceptible strains. Altogether, our findings raise hope for the future development of Ga(III)-based compounds in the treatment of infections caused by multidrug-resistant ESKAPE pathogens.