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The effect of oxygen-atom incorporation in 50-nm-thick ferroelectric Al0.89Sc0.11N films was investigated. The fabricated films exhibited a high remanent polarization ( ${P}_{\text {r}})$ exceeding $100~\mu $ C/cm2, irrespective of the oxygen content studied. An increase in oxygen content led to a decrease in coercive field ( ${E}_{\text {c}})$ from 5.2 to 4.4 MV/cm and an increase in the static dielectric constant ( $\varepsilon _{\text {i}})$ from 15 to 19. This was likely due to the formation of substitute O and Al vacancy complex defects to ease N-atom displacement. Additionally, higher oxygen content resulted in imprint effect elimination, leakage current reduction, and breakdown field ( ${E}_{\text {BD}})$ enhancement, which are beneficial for ferroelectric memory applications. The gentle and linear relationship between ${P}_{\text {r}}$ and the electric field ( ${E})$ enabled precise control of partial polarization switching, supporting multi-level operation. Although issues related to fatigue and endurance cycles remain to be addressed, the high ${P}_{\text {r}}$ and potential for multi-level operation are suitable for crossbar-based analog in-memory computing.

Seizures in people with epilepsy were long thought to occur at random, but recent methods for seizure forecasting enable estimation of the likelihood of seizure occurrence over short horizons. These methods rely on days-long cyclical patterns of brain electrical activity and other physiological variables that determine seizure likelihood and that require measurement through long-term, multimodal recordings. In this retrospective cohort study of 15 adults with bitemporal epilepsy who had a device that provides chronic intracranial recordings, functional connectivity of hippocampal networks fluctuated in multiday cycles with patterns that mirrored cycles of seizure likelihood. A functional connectivity biomarker of seizure likelihood derived from 90-s recordings of background hippocampal activity generalized across individuals and forecasted 24-h seizure likelihood as accurately as cycle-based models requiring months-long baseline recordings. Larger, prospective studies are needed to validate this approach, but our results have the potential to make reliable seizure forecasts accessible to more people with epilepsy.

In this study, quaternary InAlGaN/GaN metal-insulator-semiconductor high electron mobility transistors (MIS-HEMTs) aimed for power applications were exposed to 800 krad of Co $^{60}~\gamma $ -ray, and their response to total dose effects was recorded. For the irradiation process, devices with five gate-connected field plate schemes of field plate length (without field plate, $2~\mu $ m, 4, $\mu $ m, $6~\mu $ m, $8~\mu $ m) were tested under either a grounded state or a stressed state. It was discovered that the implementation of the field plate could successfully suppress the virtual gate phenomenon exacerbated by total dose effects. Post-irradiation analysis of the reverse characteristics also revealed that for devices irradiated under a stressed state, field plates could increase the device robustness against total dose effects impacting the electrical breakdown.

In this study, we empirically explore the performance degradation of quaternary InAlGaN/AlN/GaN Metal-Insulator-Semiconductor High Electron Mobility Transistors (MIS-HEMTs) with a Gate Field Plate (GFP) structure under a Positive Bias Temperature Instability (PBTI) and Negative Bias Temperature Instability (NBTI) stresses. Both stress conditions (PBTI with V ${_{\text {GS}}} = 10$ V and NBTI with V ${_{\text {GS}}} {=} -30$ V) are applied. The experimental findings reveal a positive shift in threshold voltage (VTH), indicating the presence of a net negative charge beneath the gate area. However, we find distinct degradation dynamics for both stress experiments. During PBTI, the ${\mathrm { V}}_{\mathrm { TH}}$ shift remains temperature independent, suggesting the generation of defects leading to electron trapping in the insulator. In NBTI, critical defects are identified, resulting in a permanent ${\mathrm { V}}_{\mathrm { TH}}$ shift with temperature dependence. Furthermore, the extracted activation energy (Ea) from Arrhenius plots in PBTI is determined to be 0.14 eV and 0.11 eV, highlighting the crucial role of shallow C-related traps governed by the Shockley-Read Hall (SRH) recombination process. In contrast, for NBTI, ${\mathrm { E}}_{\mathrm { a}} = 0.12$ eV, indicating the involvement of surface traps and thermal-assisted de-trapping kinetics, leading to the generation of permanent defects. These results underscore the distinct dynamics of performance degradation phenomena in PBTI and NBTI involves different trap energies at different locations within the device structure.

This experimental study investigates the traps dynamics and threshold voltage (VTH) shift mechanism under negative bias temperature stress for the GaN-on-Si Power MIS HEMTs on field plate design structure. Based on the experimental analysis, two distinct activation energies (Ea) have been identified under the specific reverse bias conditions of VGS= -30 V and VDS=0 V in a wide temperature range. Reverse bias stress experiments (up to 10 ks) show a positive VTH shift of ~1.6 V at room temperature due to the inversion of the charges at the interface between the insulator and AlGaN layer, resulting in net negative charge near the gate region. Subsequently, there is a decrease in VTH shift till $125~^{\circ }$ C because of the de-trapping of the inversion charges. This phenomenon shows a strong correlation with a thermally activated activation energy of (E ${_{\text {a}}}~\approx ~0.23$ eV). Further, the shift in ${\mathrm { V}}_{\mathrm { TH}}$ turns negative when the temperature is raised to $175~^{\circ }$ C, indicating the accumulation of electrons in the channel layer with activation energy (E ${_{\text {a}}}~\approx ~0.78$ eV) attributed to the activation of nitrogen interstitials from the GaN buffer layer. Additionally, the recovery (up to 10 ks) behavior demonstrates the exponential-linear settlement of the traps to recover the ${\mathrm { V}}_{\mathrm { TH}}$ shift. Moreover, nitrogen interstitials take more time to suppress the threshold voltage instabilities. These findings explain the ${\mathrm { V}}_{\mathrm { TH}}$ shift mechanisms in GaN-on-Si Power MIS HEMTs under NBTI.

This study presents the ferroelectric polarization stability characteristics of ultrathin (6 nm) superlattice (SL) ferroelectric layer metal-ferroelectric-metal (MFM) capacitors fabricated with varying ferroelectric layer stacks. Notably, ZrO2-HfO2 SL MFM capacitors with 1 nm ZrO2 as the starting layer exhibited enhanced polarization stability characterized by nearly wake-up free and fatigue-free behavior. The research demonstrates the deposition of ZrO2-HfO2 superlattice by atomic layer deposition (ALD), resulting in highly stable remanent polarization (2Pr @ 3.3 MV/cm) of approximately $30~\mu $ C/cm2. The variation remained small ( $\Delta 2$ P $_{\text {r}} \le 2.5~\mu $ C/cm2; $\Delta 2$ Pr/2P $_{\text {r, {pristine}}} \le 8$ %) over an impressive $10^{{10}}$ cycles of field cycling. This result is a crucial technique to address the polarization instability commonly reported in ultrathin ( $\le 6$ nm) Hf $_{{0}.{5}}$ Zr $_{{0}.{5}}$ O by utilizing the SL structure to achieve nearly wake-up free and fatigue-free polarization performance up to $10^{{10}}$ cycles.

In this article, we propose the novel core-shell Si/InxGa $_{{1}- {x}}$ As FinFETs, where an In $_{{0}.{53}}$ Ga $_{{0}.{47}}$ As shell channel was epitaxially grown on a silicon core fin. Based on the model calibrated using conventional bulk In $_{{0}.{53}}$ Ga $_{{0}.{47}}$ As FinFET, the device characteristics, including dc and RF performance of the core-shell FinFET, were analyzed and compared with the bulk FinFET. Due to the conduction band offset between InxGa $_{{1}- {x}}$ As shell and Si fin, a quantum well is formed in the InxGa $_{{1}- {x}}$ As channel region, which is lying between the high dielectric constant (HK) gate and the Si core. The advantages of the core-shell FinFET include increasing the gate controllability, enhancing the effective bandgap, and reducing the leakage current, while the on-state performance in transconductance ( ${g}_{m}\text {)}$ and drain current ( ${I}_{\text {ON}}\text {)}$ is maintained. The effects of varying the channel thickness, length, and the indium content of the InxGa $_{{1}- {x}}$ As shell are also explored in both dc and RF aspects. The results show that the core-shell FinFET exhibits superior characteristics in terms of leakage current, subthreshold swing, and drain-induced barrier lowering, owing to its superior gate controllability, with comparable RF performance in current gain cutoff frequency ( ${f}_{t} \gt 400$ GHz for 50-nm ${L}_{\text {Ch}}\text {)}$ with the bulk FinFET. The major objective of this article is to provide the possible directions for the design of the Si/InxGa $_{{1}- {x}}$ As core-shell FinFET for future device applications.

Loss of speech after paralysis is devastating, but circumventing motor-pathway injury by directly decoding speech from intact cortical activity has the potential to restore natural communication and self-expression. Recent discoveries have defined how key features of speech production are facilitated by the coordinated activity of vocal-tract articulatory and motor-planning cortical representations. In this Review, we highlight such progress and how it has led to successful speech decoding, first in individuals implanted with intracranial electrodes for clinical epilepsy monitoring and subsequently in individuals with paralysis as part of early feasibility clinical trials to restore speech. We discuss high-spatiotemporal-resolution neural interfaces and the adaptation of state-of-the-art speech computational algorithms that have driven rapid and substantial progress in decoding neural activity into text, audible speech, and facial movements. Although restoring natural speech is a long-term goal, speech neuroprostheses already have performance levels that surpass communication rates offered by current assistive-communication technology. Given this accelerated rate of progress in the field, we propose key evaluation metrics for speed and accuracy, among others, to help standardize across studies. We finish by highlighting several directions to more fully explore the multidimensional feature space of speech and language, which will continue to accelerate progress towards a clinically viable speech neuroprosthesis.

Advances in large-scale single-unit human neurophysiology, single-cell RNA sequencing, spatial transcriptomics and long-term ex vivo tissue culture of surgically resected human brain tissue have provided an unprecedented opportunity to study human neuroscience. In this Perspective, we describe the development of these paradigms, including Neuropixels and recent brain-cell atlas efforts, and discuss how their convergence will further investigations into the cellular underpinnings of network-level activity in the human brain. Specifically, we introduce a workflow in which functionally mapped samples of human brain tissue resected during awake brain surgery can be cultured ex vivo for multi-modal cellular and functional profiling. We then explore how advances in human neuroscience will affect clinical practice, and conclude by discussing societal and ethical implications to consider. Potential findings from the field of human neuroscience will be vast, ranging from insights into human neurodiversity and evolution to providing cell-type-specific access to study and manipulate diseased circuits in pathology. This Perspective aims to provide a unifying framework for the field of human neuroscience as we welcome an exciting era for understanding the functional cytoarchitecture of the human brain.

Understanding the neural basis of speech perception requires that we study the human brain both at the scale of the fundamental computational unit of neurons and in their organization across the depth of cortex. Here we used high-density Neuropixels arrays1–3to record from 685 neurons across cortical layers at nine sites in a high-level auditory region that is critical for speech, the superior temporal gyrus4,5, while participants listened to spoken sentences. Single neurons encoded a wide range of speech sound cues, including features of consonants and vowels, relative vocal pitch, onsets, amplitude envelope and sequence statistics. Neurons at each cross-laminar recording exhibited dominant tuning to a primary speech feature while also containing a substantial proportion of neurons that encoded other features contributing to heterogeneous selectivity. Spatially, neurons at similar cortical depths tended to encode similar speech features. Activity across all cortical layers was predictive of high-frequency field potentials (electrocorticography), providing a neuronal origin for macroelectrode recordings from the cortical surface. Together, these results establish single-neuron tuning across the cortical laminae as an important dimension of speech encoding in human superior temporal gyrus.

Despite increasing prevalence and huge personal and societal burden, psychiatric diseases still lack treatments which can control symptoms for a large fraction of patients. Increasing insight into the neurobiology underlying these diseases has demonstrated wide-ranging aberrant activity and functioning in multiple brain circuits and networks. Together with varied presentation and symptoms, this makes one-size-fits-all treatment a challenge. There has been a resurgence of interest in the use of neurostimulation as a treatment for psychiatric diseases. Initial studies using continuous open-loop stimulation, in which clinicians adjusted stimulation parameters during patient visits, showed promise but also mixed results. Given the periodic nature and fluctuations of symptoms often observed in psychiatric illnesses, the use of device-driven closed-loop stimulation may provide more effective therapy. The use of a biomarker, which is correlated with specific symptoms, to deliver stimulation only during symptomatic periods allows for the personalized therapy needed for such heterogeneous disorders. Here, we provide the reader with background motivating the use of closed-loop neurostimulation for the treatment of psychiatric disorders. We review foundational studies of open- and closed-loop neurostimulation for neuropsychiatric indications, focusing on deep brain stimulation, and discuss key considerations when designing and implementing closed-loop neurostimulation.

In this study, we investigate the device characteristics and reliability of the hybrid ferroelectric charge trap gate-stack enhancement-mode gallium nitride MIS-high electron mobility transistors (FEG-HEMTs) with various doping elements in the charge trapping layer (CTL). FEG-HEMTs were fabricated with fluorine-doped (F-HfO2) and nitrogen-doped HfO2 (HfON) films as the CTLs. Incorporating fluorine and nitrogen into HfO2 resulted in a notable decrease in oxygen vacancy and dangling bond densities. This, in turn, improved the interface stability and subsequently enhanced the device performance and reliability. The F-doped FEG-HEMT was confirmed to have high performance as well as high stability with high threshold voltage ( ${V}_{\text {th}})$ of 5.43 V, maximum drain current ( ${I}_{\text {D, {MAX}}})$ of 760.2 mA/mm, and breakdown voltage (BV) of 906 V. Furthermore, stress gate BV, retention time, time-dependent dielectric breakdown (TDDB), and constant stress bias test, which contribute significantly to the reliability of FEG gate-stack, are reported in this article.

In this article, we have demonstrated the utilization of innovative atomic-layer-deposited (ALD) ultrathin (~1.8 nm) amorphous InSnZnO ( $\alpha $ -ITZO) channel material in the development of a back-end-of-line (BEOL) compatible thin film transistor (TFT). Through the optimization of the indium/tin/zinc (In/Sn/Zn) ratio, the bottom gate (BG) TFT with In0.83Sn0.11Zn0.06O channel and the channel length ( ${L}_{\text {ch}}$ ) of 40 nm demonstrates remarkable performances, including positive threshold voltage ( ${V}_{\text {th}}$ ) of 0.38 V, excellent subthreshold swing (SS) value of 66.4 mV/dec, high field-effect mobility ( $\mu _{\text {FE}}$ ) of 48 cm2/V-s, maximum ON-state current density ( ${I}_{\text {ON}}$ ) of $686~\mu \text{A}/\mu \text{m}$ at ${V}_{\text {DS}}$ = 2 V (@ ${V}_{G}$ = 4 V), and extremely low drain-induced barrier lowering (DIBL) performance of 22 mV/V. Furthermore, the excellent stabilities of the $\alpha $ -ITZO TFT were shown by negative bias stress (NBS) and positive bias stress (PBS) under ${V}_{G}$ of ( ${V}_{\text {th}}~\pm $ 3 V), and ${V}_{\text {th}}$ shift ( $\Delta {V}_{\text {th}}$ ) of −40 and 60 mV ( ${L}_{\text {ch}}$ = 700 nm) after 3600 s was exhibited. We also simulated the current gain cutoff frequency ( ${f}_{T}$ ) by technology computer-aided design (TCAD) simulation to further investigate the potential of radio frequency (RF) applications. These results establish a competitive standard for TFTs based on quaternary ultrathin ( ${T}_{\text {ch}} < 5$ nm) amorphous oxide semiconductors (AOSs).

The human auditory system extracts rich linguistic abstractions from speech signals. Traditional approaches to understanding this complex process have used linear feature-encoding models, with limited success. Artificial neural networks excel in speech recognition tasks and offer promising computational models of speech processing. We used speech representations in state-of-the-art deep neural network (DNN) models to investigate neural coding from the auditory nerve to the speech cortex. Representations in hierarchical layers of the DNN correlated well with the neural activity throughout the ascending auditory system. Unsupervised speech models performed at least as well as other purely supervised or fine-tuned models. Deeper DNN layers were better correlated with the neural activity in the higher-order auditory cortex, with computations aligned with phonemic and syllabic structures in speech. Accordingly, DNN models trained on either English or Mandarin predicted cortical responses in native speakers of each language. These results reveal convergence between DNN model representations and the biological auditory pathway, offering new approaches for modeling neural coding in the auditory cortex.

The high-performance atomic layer deposited (ALD) ultrathin (~2 nm) amorphous InZnO ( ${a}$ -IZO, indium: Zinc ≈ 6:4) channel thin-film transistors (TFTs) with a short channel length ( $\text{L}_{\mathbf {\textit {ch}}}$ ) of 50 nm were presented. Furthermore, the gate stability was evaluated using temperature-dependent positive-bias stress (PBS) tests for the IZO TFTs up to 3.5 MV/cm. The short channel TFTs exhibited excellent electrical characteristics, with high $\text{I}_{\mathbf {\textit {on}}}$ exceeding $360~\mu \text{A} / \mu \text{m}$ (@ $\text{V}_{\mathbf {G}}$ = 2V), and an optimized threshold voltage ( $\text{V}_{\mathbf {\textit {th}}}$ ) of ~ 0.11 V. In particular, the ultra-low drain-induced barrier lowering (DIBL) performance of 16 mV/V was presented and matched with technology computer aided design (TCAD) estimation. The activation energy of device degradation was extracted to better understand the mechanism. The extracted high field effect channel mobility ( $\mu _{\mathbf {\textit {FE}}}$ ) of 43.6 cm $^{\mathbf {{2}}}$ /V-s in conjunction with the low $\text{V}_{\mathbf {\textit {th}}}$ shifts of 12.4 mV (@ 3.5 MV/cm; $\text{V}_{\mathbf {\textit {th}}}$ +2V) for 5000s PBS test at $25^{\mathbf {o}}$ C exhibited the excellent performances combining channel mobility and gate stability reported for oxide semiconductor TFT.

This article investigates a hybrid ferroelectric charge trap (HFCT)-based HfZrO4/HfOXNY/ Al2O3/AlGaN/GaN gate-stack under constant positive gate voltage stress over time and temperature variability. The experimentally characterized breakdown (BD) analysis implies a thermally assisted tunneling (TAT) BD owing to the negative temperature coefficient of BD voltage. Moreover, the step gate stress depicts a relatively lower BD voltage of ~20 V compared to the linear gate stress voltage of ~21.85 V attributed to performance degradation due to stress. In addition, the Weibull distribution, which validates the intrinsic degradation of the gate-stack, is used to estimate its lifetime. An operating voltage of ~7.41 V exhibits a ten-year lifetime at 150 °C extrapolated over multiple stress conditions. Furthermore, the activation energy from ~0.63 to ~0.67 eV validates deep-level E3 traps within the GaN barrier layer and the trapping of electrons during degradation, thus, revealing the point-level defect generation leading to the time-dependent gate dielectric BD (TDDB). The robustness and superior reliability of the HFCT gate-stack are recognized, and the single degradation mechanism contributes to the final device failure in the TDDB test.

Speech neuroprostheses have the potential to restore communication to people living with paralysis, but naturalistic speed and expressivity are elusive1. Here we use high-density surface recordings of the speech cortex in a clinical-trial participant with severe limb and vocal paralysis to achieve high-performance real-time decoding across three complementary speech-related output modalities: text, speech audio and facial-avatar animation. We trained and evaluated deep-learning models using neural data collected as the participant attempted to silently speak sentences. For text, we demonstrate accurate and rapid large-vocabulary decoding with a median rate of 78 words per minute and median word error rate of 25%. For speech audio, we demonstrate intelligible and rapid speech synthesis and personalization to the participant’s pre-injury voice. For facial-avatar animation, we demonstrate the control of virtual orofacial movements for speech and non-speech communicative gestures. The decoders reached high performance with less than two weeks of training. Our findings introduce a multimodal speech-neuroprosthetic approach that has substantial promise to restore full, embodied communication to people living with severe paralysis.

Chronic pain syndromes are often refractory to treatment and cause substantial suffering and disability. Pain severity is often measured through subjective report, while objective biomarkers that may guide diagnosis and treatment are lacking. Also, which brain activity underlies chronic pain on clinically relevant timescales, or how this relates to acute pain, remains unclear. Here four individuals with refractory neuropathic pain were implanted with chronic intracranial electrodes in the anterior cingulate cortex and orbitofrontal cortex (OFC). Participants reported pain metrics coincident with ambulatory, direct neural recordings obtained multiple times daily over months. We successfully predicted intraindividual chronic pain severity scores from neural activity with high sensitivity using machine learning methods. Chronic pain decoding relied on sustained power changes from the OFC, which tended to differ from transient patterns of activity associated with acute, evoked pain states during a task. Thus, intracranial OFC signals can be used to predict spontaneous, chronic pain state in patients.

Gliomas synaptically integrate into neural circuits1,2. Previous research has demonstrated bidirectional interactions between neurons and glioma cells, with neuronal activity driving glioma growth1–4and gliomas increasing neuronal excitability2,5–8. Here we sought to determine how glioma-induced neuronal changes influence neural circuits underlying cognition and whether these interactions influence patient survival. Using intracranial brain recordings during lexical retrieval language tasks in awake humans together with site-specific tumour tissue biopsies and cell biology experiments, we find that gliomas remodel functional neural circuitry such that task-relevant neural responses activate tumour-infiltrated cortex well beyond the cortical regions that are normally recruited in the healthy brain. Site-directed biopsies from regions within the tumour that exhibit high functional connectivity between the tumour and the rest of the brain are enriched for a glioblastoma subpopulation that exhibits a distinct synaptogenic and neuronotrophic phenotype. Tumour cells from functionally connected regions secrete the synaptogenic factor thrombospondin-1, which contributes to the differential neuron–glioma interactions observed in functionally connected tumour regions compared with tumour regions with less functional connectivity. Pharmacological inhibition of thrombospondin-1 using the FDA-approved drug gabapentin decreases glioblastoma proliferation. The degree of functional connectivity between glioblastoma and the normal brain negatively affects both patient survival and performance in language tasks. These data demonstrate that high-grade gliomas functionally remodel neural circuits in the human brain, which both promotes tumour progression and impairs cognition.

Muscle flaps must have a strong vascular network to support a large tissue volume and ensure successful engraftment. We developed porcine stomach musculofascial flap matrix (PDSF) comprising extracellular matrix (ECM) and intact vasculature. PDSF had a dominant vascular pedicle, microcirculatory vessels, a nerve network, well-retained 3-dimensional (3D) nanofibrous ECM structures, and no allo- or xenoantigenicity. In-depth proteomic analysis demonstrated that PDSF was composed of core matrisome proteins (e.g., collagens, glycoproteins, proteoglycans, and ECM regulators) that, as shown by Gene Ontology term enrichment analysis, are functionally related to musculofascial biological processes. Moreover, PDSF−human adipose-derived stem cell (hASC) synergy not only induced monocytes towards IL-10−producing M2 macrophage polarization through the enhancement of hASCs' paracrine effect but also promoted the proliferation and interconnection of both human skeletal muscle myoblasts (HSMMs) and human umbilical vein endothelial cells (HUVECs) in static triculture conditions. Furthermore, PDSF was successfully prevascularized through a dynamic perfusion coculture of hASCs and HUVECs, which integrated with PDSF and induced the maturation of vascular networks in vitro. In a xenotransplantation model, PDSF demonstrated myoconductive and immunomodulatory properties associated with the predominance of M2 macrophages and regulatory T cells. In a volumetric muscle loss (VML) model, prevascularized PDSF augmented neovascularization and constructive remodeling, which was characterized by the predominant infiltration of M2 macrophages and significant musculofascial tissue formation. These results indicate that hASCs' integration with PDSF enhances the cells’ dual function in immunomodulation and angiogenesis. Owing in part to this PDSF-hASC synergy, our platform shows promise for vascularized muscle flap engineering for VML reconstruction.

A computer screen shows the question “Would you like some water?” Underneath, three dots blink, followed by words that appear, one at a time: “No I am not thirsty.” • It was brain activity that made those words materialize—the brain of a man who has not spoken for more than 15 years, ever since a stroke damaged the connection between his brain and the rest of his body, leaving him mostly paralyzed. He has used many other technologies to communicate; most recently, he used a pointer attached to his baseball cap to tap out words on a touch screen, a method that was effective but slow. He volunteered for my research group's clinical trial at the University of California, San Francisco in hopes of pioneering a faster method. So far, he has used the brain-to-text system only during research sessions, but he wants to help develop the technology into something that people like himself could use in their everyday lives.

In this article, enhancement-mode thin-film transistors (TFTs) with atomic layer deposition (ALD)-derived ultrathin (≈3 nm) amorphous indium–zinc oxide (a-IZO) channel were demonstrated. Our devices showed improved device characteristics as benchmarked with thicker IZO thin-film channels. The ALD-deposited IZO channel TFT with an In/Zn ratio of ≈6:4 exhibited a high field-effect channel mobility ( $\mu _{\text {FE}}{)}$ of 53.6 cm2/V-s, a threshold voltage ( ${V}_{\text {th}}{)}$ of 0.28 V, a low subthreshold gate swing of 74 mV/decade, an $I_{ \mathrm{\scriptscriptstyle ON}}/I_{ \mathrm{\scriptscriptstyle OFF}}$ ratio of > $10^{{9}}$ , and a contact resistance of 0.18 $\text{k}\Omega $ - $\mu \text{m}$ after 300°C anneal in oxygen atmosphere. Physical analysis, including X-ray and ultraviolet (UV) photoelectron spectra of IZO films, was conducted to understand the mechanisms of enhancement in electrical performance after annealing. The threshold voltages of the TFT also exhibited high stability ( $\Delta {V}_{\text {th, PBS}} < 16$ mV and $\Delta {V}_{\text {th, NBS}} < 12$ mV) after positive bias stress (PBS) and negative bias stress (NBS) test for 3600 s. To the best of our knowledge, we reported the TFT with thinnest IZO ternary oxide semiconductor (OS) channel exhibiting superior channel mobility and subthreshold characteristics.

In this work, a Schottky Barrier Diode (SBD) with an optimized ladder-shaped hybrid anode (LSHA) is demonstrated. The SBD devices in this work were fabricated on a GaN-on-Si wafer with in situ Si3N4 cap layer. To form the LSHA, a two-step recessed process was implemented. For device optimization, the recess depths of the two recess steps were carefully optimized. Devices with different LSHA recess profiles were fabricated, and their electrical characteristics were evaluated by measuring the forward current, reverse current and breakdown voltage (BV). Optimized device exhibited a low reverse leakage current ( ${I}_{R}$ ) of ${5.66} \times {10} ^{-{8}}$ (A/mm), a low turn-on voltage ( ${V}_{T}$ ) of 0.315 V, and a BV over 1000 V. In addition, ${I}_{R}$ (A/mm) versus ${V}_{T}$ ( ${V}$ ) of this work and ${R}_{{\text {on}, \text {SP}}}$ ( $\text{m}\Omega \cdot $ cm2) versus BV ( ${V}$ ) of this work are benchmarked. We demonstrated the lowest ${I}_{R}$ among the GaN SBDs with ${V}_{T} < 0.4$ V and the outstanding performance of ${R}_{{\text {on}, \text {SP}}}$ (0.88 $\text{m}\Omega \cdot $ cm2) with a hard BV of over 1000 V (1020 V) using the LSHA-SBD.