Search

Recent advancements in computational performance and medical simulation technology have made significant strides, particularly in predictive diagnosis. This study focuses on the blood flow simulation reduced-order models, which provide swift and cost-effective solutions for complex vascular systems, positioning them as practical alternatives to 3D simulations in resource-limited medical settings. The paper introduces a visualization platform for patient-specific and image-based 1D–0D simulations. This platform covers the entire workflow, from modeling to dynamic 3D visualization of simulation results. Two case studies on, respectively, carotid stenosis and arterial remodeling demonstrate its utility in blood flow simulation applications. [ABSTRACT FROM AUTHOR]

Threshold voltage defined by a band bending of twice the substrate intrinsic-to-Fermi level difference has been widely accepted. However, there are shortcomings with this analytical definition. Since the inversion condition is governed by the substrate Fermi level (i.e., majority carrier density per volume), inversion carrier density per area at threshold inadequately depends on substrate doping and temperature. Another problem is that the definition is not applicable to fully depleted thin body devices, such as FinFETs and silicon-on-insulator FETs, widely used today. To solve these problems, a new definition of threshold voltage is proposed, which is based on a standardized charge versus voltage relationship of ideal metal-oxide-semiconductor capacitors. Threshold voltage is specified by a threshold inversion carrier density per area, which is a simple function of gate oxide capacitance and thermal voltage. Dependence of the proposed threshold voltage on substrate doping, body thickness, and temperature for both bulk and double-gate FETs is discussed using semi-classical analytical equations. [ABSTRACT FROM AUTHOR]

GeO2 was grown by a slot-plane-antenna (SPA) high density radical oxidation, and the oxidation kinetics of radical oxidation GeO2 was examined. By the SPA radical oxidation, no substrate orientation dependence of growth rate attributed to highly reactive oxygen radicals with low oxidation activation energy was demonstrated, which is highly beneficial to three-dimensional structure devices, such as multigate field-effect transistors, to form conformal gate dielectrics. The electrical properties of an aluminum oxide (Al2O3) metal-oxide-semiconductor gate stack with a GeO2 interfacial layer were investigated, showing very low interface state density (Dit), 1.4×1011 cm-2 eV-1. By synchrotron radiation photoemission spectroscopy, the conduction and the valence band offsets of GeO2 with respect to Ge were estimated to be 1.2±0.3 and 3.6±0.1 eV, which are sufficiently high to suppress gate leakage. [ABSTRACT FROM AUTHOR]

Schottky barrier height modulation in metal/Ge Schottky junction was demonstrated by inserting an ultrathin interfacial silicon nitride layer. The SiN interfacial layer suppressed strong Fermi level pinning in metal/Ge Schottky junction, which resulted in effective control of Schottky barrier height. Metal/SiN/Ge Schottky diode was systematically investigated in terms of SiN thickness dependence and metal work function dependence. At an optimal SiN thickness, Ohmic contact between metal and Ge was obtained as a result of Fermi level depinning, and almost ideal Schottky barrier height determined by the work function difference between the metal and Ge was achieved. This technology was finally applied to metal source/drain Ge metal-oxide-semiconductor field-effect-transistors with low source/drain resistance. [ABSTRACT FROM AUTHOR]

The effects of quantum confinement on transport properties of silicon nanowire metal-oxide-semiconductor field-effect transistors (FETs) and single-electron transistors are experimentally investigated. By carefully designing the channel width, the nanowire transistors operate as silicon nanowire FETs (SNWFETs) or single-charge transistors. Large quantum confinement in ultranarrow silicon nanowires plays a key role in these devices. We also adopt a special device configuration in which both n-type and p-type operations can be attained in an identical device, and the dependence on the channel direction and charge polarity is intensively investigated. Statistical measurements and band structure calculation reveal that [110] p-channel SNWFETs show smaller threshold voltage variations and [100] single-hole transistors show the largest Coulomb blockade oscillations at room temperature. [ABSTRACT FROM AUTHOR]

HfO2-based ferroelectrics are one of the most actively developed functional materials for memory devices. However, in HfO2-based ferroelectric devices, dielectric breakdown is a main failure mechanism during repeated polarization switching. Elucidation of the breakdown process may broaden the scope of applications for the ferroelectric HfO2. Here, we report direct observations of a breakdown process in HfO2-based ferroelectric capacitors, by in situ laser-based photoemission electron microscopy. We have not only clearly visualized the hard dielectric breakdown (HDB) spot but also observed the regions responsible for the soft dielectric breakdown (SDB), which is a precursor phenomenon to HDB. It was found that the low-resistance region formed after SDB is wider than the conduction path formed after HDB. Furthermore, our spectromicroscopic analysis revealed that the photoelectron spectrum after SDB shows an enhancement in intensity without spectral-shape modulation, interpreted that the initially existed defects are increased. In the HDB spot, however, an additional shoulder structure was observed. These results provide spectroscopic evidence that the electronic states responsible for the conduction path after SDB are different from those after HDB. Through this work, we propose this microscopic approach as a versatile tool for studying buried materials as they are, accelerating the development of material engineering for advanced electronic devices. [ABSTRACT FROM AUTHOR]

We determined optimal inclusion relations between L p -Sobolev and Wiener amalgam spaces. For applications, we discuss mapping properties of unimodular Fourier multipliers e i | D | α between L p -Sobolev and Wiener amalgam spaces and derive some Littlewood–Paley type inequalities. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we give new estimates for the solution to the Schrödinger equation with quadratic and sub-quadratic potentials in the framework of modulation spaces. [Copyright &y& Elsevier]

Abstract: The inclusion relations between the -Sobolev spaces and the modulation spaces is determined explicitly. As an application, mapping properties of unimodular Fourier multiplier between -Sobolev spaces and modulation spaces are discussed. [Copyright &y& Elsevier]

Ge is one of the promising candidates for high-mobility channel material in future complementary metal–oxide–semiconductor technology. High-field transport in short-channel Ge p-channel field-effect transistors (PFETs) needs to be examined since device performance is determined by high-field velocity in quasi-ballistic transport regime. In this paper, ballisticity and the relationship between carrier velocity and mobility in short-channel (70-nm) Ge PFETs were thoroughly investigated. A \1.6\times-\2\times higher velocity was confirmed in Ge PFETs than that in Si PFETs. Uniaxial stress is also a strong performance booster besides high-mobility substrate. The effectiveness of the uniaxial stress to velocity enhancement in Ge PFETs was experimentally demonstrated in short channel regime. A \1.4\times higher drive current can be achievable by uniaxially strained Ge PFET in ballistic transport regime as compared with strained Si PFET. [ABSTRACT FROM AUTHOR]

Ge channel is one of the promising performance boosters for replacing Si channel in future complementary metal-oxide-semiconductor technology. The uniaxial stress technology can further enhance the performance of Ge MOSFETs. In this paper, the uniaxial stress effect on Ge NMOSFETs was experimentally and theoretically investigated. The gate dielectric in the Ge NMOSFETs was fabricated by using the novel radical oxidation technique. The high quality of the gate dielectric allowed high vertical field mobilitymeasurements. By applying mechanical uniaxial stress on the fabricated Ge NMOSFETs, the mobility enhancement was experimentally obtained. The physical mechanism of mobility enhancement under such strain indicates that the device performance of Ge NMOSFETs in the ballistic transport regime can achieve as much as 48% drive current gain beyond the 15 nm technology node. [ABSTRACT FROM AUTHOR]

Abstract: The results of Sjöstrand [J. Sjöstrand, An algebra of pseudodifferential operators, Math. Res. Lett. 1 (1994) 185–192] and Sugimoto [M. Sugimoto, -boundedness of pseudo-differential operators satisfying Besov estimates, I, J. Math. Soc. Japan 40 (1988) 105–122] on a mapping property of pseudo-differential operators are two different kinds of extensions of the pioneering work by Calderón and Vaillancourt [A.P. Calderón, R. Vaillancourt, On the boundedness of pseudo-differential operators, J. Math. Soc. Japan 23 (1971) 374–378]. The objective of this paper is to show that these two results, which appeared to be independent ones, can be proved based on the same principle. For the purpose, we use the α-modulation spaces, a parameterized family of function spaces, which include Besov spaces and modulation spaces as special cases. As an application, we also discuss the -boundedness of the commutator , where is a Lipschitz function and σ belongs to an α-modulation space. [Copyright &y& Elsevier]

Boron is toxic to living organisms when present in excess. Saccharomyces cerevisiae Bor1p is a plasma membrane protein that decreases the intracellular concentration of boron and confers boron tolerance in yeasts. We investigated the detailed characteristics of boron transport by Bor1p and its roles in boron tolerance. Boron transport assays showed that the bor1 deletion mutant ( bor1Δ) accumulates higher intracellular concentrations of boron and has a lower rate of boron export. The bor1Δ showed greater susceptibility to high concentrations of boron than the wild-type strain, and the growth rates of both strains were negatively correlated with the intracellular concentrations of boron. With normal to toxic levels of external boron, green fluorescent protein (GFP)-tagged Bor1p localized to the plasma membrane irrespective of the concentration of boron in the medium. Taken together, these results establish Bor1p as a plasma membrane boron exporter and a key determinant of boron tolerance. [ABSTRACT FROM AUTHOR]

• Conventional spline fitting (SFM) uses cubic B-spline and 2nd derivative penalty. • Our SFM (geo-SFM) provides optimized curvature-torsion (C-T) graph along arteries. • geo-SFM was applied to both stent graft in AAA and cerebral arteries with aneurysms. • Temporal changes of bending positions along stent graft were observed in C-T graph. • Torsion graph by geo-SFM enabled us to observe helical directions clearly. In order to grasp the spatial and temporal evolution of vascular geometry, three-dimensional (3D) arterial bending structure and geometrical changes of arteries and stent grafts (SG) must be quantified using geometrical parameters such as curvature and torsion along the vasculature centerlines extracted from medical images. Here, we develop a robust method for constructing smooth centerlines based on a spline fitting method (SFM) such that the optimized geometric parameters of curvature and torsion can be obtained independently of digitization noise in the images. Conventional SFM consists of the 3rd degree spline basis function and 2nd derivative penalty term. In contrast, the present SFM uses the 5th degree spline basis function and 3rd and 4th derivative penalty terms, the coefficients of which are derived by the Akaike information criterion. The results show that the developed SFM can reduce the errors of curvature and torsion compared to conventional SFM. We then apply the present SFM to the centerline of the SG in an abdominal aortic aneurysm (AAA), and those of bilateral internal carotid arteries (ICA) in 6 cases: 3 cases with aneurysms and 3 cases without any aneurysm. The SG centerlines were obtained from temporal medical images at three scan times. The strong peak of the curvature could be clearly observed in the distal area of the SG, the inversion of the torsion at 0 months in the middle area of SG disappeared over time, and the torsions around the SG bifurcation at the three time periods were inverted. The curvature-torsion graphs along the ICA centerlines superimposing five aneurysmal positions were useful for investigating the relationship between arterial bending structure and aneurysmal positions. Both ICAs had curvature peak values higher than 0.4 within the ICA syphons. The ICA torsion graphs indicated that left and right ICA tended to be a right- and left-handed helix, respectively. In the left ICA syphon, the biggest aneurysm could be observed downstream of the salient torsion inversion. All aneurysms for 3 cases were positioned at the downstream of the inverted torsion. [ABSTRACT FROM AUTHOR]

Low-temperature characterization has been performed on fully depleted silicon-on-insulator (FDSOI) field-effect-transistor (FET) with gate length (Lg) down to 25 nm to clarify transport mechanisms that determine device performance in deca-nanometer scale. Linear drain current of FDSOI FET follows Lg-1 scaling down to 25 nm Lg, where mobility dominates, while saturation drain current largely deviates from Lg-1 scaling. Temperature dependence of effective source velocity at high drain voltage (Vds) is weaker than that at low Vds in short Lg and is consistent with that of saturation velocity. Drift velocity measurement revealed velocity overshooting behavior at high lateral field, indicating further Lg scaling benefit. [ABSTRACT FROM AUTHOR]

The effect of the surface passivation with ex situ wet clean as well as insertion of an III-V in situ grown interlayer, on the HfO2/In0.52Al0.48As interface characteristics was investigated with capacitance/conductance measurements, and synchrotron radiation photoemission spectroscopy. A very thin aluminum oxide passivation layer grown after In0.52Al0.48As surface clean improves the In0.52Al0.48As metal-oxide-semiconductor characteristics compared to native oxide covered interface, giving an interface state density (Dit) 3.8×1012 cm-2 eV-1 at 0.31 eV from conduction band edge. Furthermore, insertion of a thin In0.53Ga0.47As cap layer effectively prevented Al oxidation further improving electrical properties, such as frequency dispersion, hysteresis, Dit (2.7×1012 cm-2 eV-1) and capacitive equivalent oxide thickness. [ABSTRACT FROM AUTHOR]

We have investigated the energy efficiency and scalability of ferroelectric HfO 2 (FE:HfO 2 )-based negative-capacitance field-effect-transistor (NCFET) with gate-all-around (GAA) nanowire (NW) channel structure. Analytic simulation is conducted to characterize NW-NCFET by varying NW diameter and/or thickness of gate insulator as device structural parameters. Due to the negative-capacitance effect and GAA NW channel structure, NW-NCFET is found to have 5× higher I on /I off ratio than classical NW-MOSFET and 2× higher than double-gate (DG) NCFET, which results in wider design window for high I on /I off ratio. To analyze these obtained results from the viewpoint of the device scalability, we have considered constraints regarding very limited device structural spaces to fit by the gate insulator and NW channel for aggresively scaled gate length (L g ) and/or very tight NW pitch. NW-NCFET still has design point with very thinned gate insulator and/or narrowed NW. Therefore, FE:HfO 2 -based NW-NCFET is applicable to the aggressively scaled technology node of sub-10 nm L g and to the very tight NW integration of sub-30 nm NW pitch for beyond 7 nm technology. [ABSTRACT FROM AUTHOR]

HfO2-based ferroelectric (FE–HfO2) is a promising material for low-power and high-capacity memory technology. Since thinner ferroelectric films are required for low voltage operation, the impact of film thickness on the switching kinetics of FE–HfO2 needs to be studied in detail. In this paper, metal/ferroelectric/metal capacitors are fabricated with several thicknesses of HfZrO2 (HZO) films and characterized to study the switching kinetics based on the nucleation limited switching (NLS) model. Thinner HZO capacitors show slower polarization switching and asymmetry in program and erase operation, although low-frequency polarization charge density is nearly the same for all thicknesses. Slow switching is due to the large variability of the activation field of FE domains and grain boundaries among small FE grains. The asymmetry is caused by the asymmetric interface property at the top and bottom interfaces. High-resolution TEM and electron diffraction mapping methods provide physical evidence for the above discussions. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to assess the efficiency of artificial intelligence (AI) in the detection of visceral pleural invasion (VPI) of lung cancer using high-resolution computed tomography (HRCT) images, which is challenging for experts because of its significance in T-classification and lymph node metastasis prediction.This retrospective analysis was conducted on preoperative HRCT images of 472 patients with stage I non-small cell lung cancer (NSCLC), focusing on lesions adjacent to the pleura to predict VPI. YOLOv4.0 was utilized for tumor localization, and EfficientNetv2 was applied for VPI prediction with HRCT images meticulously annotated for AI model training and validation.Of the 472 lung cancer cases (500 CT images) studied, the AI algorithm successfully identified tumors, with YOLOv4.0 accurately localizing tumors in 98% of the test images. In the EfficientNet v2-M analysis, the receiver operating characteristic curve exhibited an area under the curve of 0.78. It demonstrated powerful diagnostic performance with a sensitivity, specificity, and precision of 76.4% in VPI prediction.AI is a promising tool for improving the diagnostic accuracy of VPI for NSCLC. Furthermore, incorporating AI into the diagnostic workflow is advocated because of its potential to improve the accuracy of preoperative diagnosis and patient outcomes in NSCLC.Methods: This study aimed to assess the efficiency of artificial intelligence (AI) in the detection of visceral pleural invasion (VPI) of lung cancer using high-resolution computed tomography (HRCT) images, which is challenging for experts because of its significance in T-classification and lymph node metastasis prediction.This retrospective analysis was conducted on preoperative HRCT images of 472 patients with stage I non-small cell lung cancer (NSCLC), focusing on lesions adjacent to the pleura to predict VPI. YOLOv4.0 was utilized for tumor localization, and EfficientNetv2 was applied for VPI prediction with HRCT images meticulously annotated for AI model training and validation.Of the 472 lung cancer cases (500 CT images) studied, the AI algorithm successfully identified tumors, with YOLOv4.0 accurately localizing tumors in 98% of the test images. In the EfficientNet v2-M analysis, the receiver operating characteristic curve exhibited an area under the curve of 0.78. It demonstrated powerful diagnostic performance with a sensitivity, specificity, and precision of 76.4% in VPI prediction.AI is a promising tool for improving the diagnostic accuracy of VPI for NSCLC. Furthermore, incorporating AI into the diagnostic workflow is advocated because of its potential to improve the accuracy of preoperative diagnosis and patient outcomes in NSCLC.Results: This study aimed to assess the efficiency of artificial intelligence (AI) in the detection of visceral pleural invasion (VPI) of lung cancer using high-resolution computed tomography (HRCT) images, which is challenging for experts because of its significance in T-classification and lymph node metastasis prediction.This retrospective analysis was conducted on preoperative HRCT images of 472 patients with stage I non-small cell lung cancer (NSCLC), focusing on lesions adjacent to the pleura to predict VPI. YOLOv4.0 was utilized for tumor localization, and EfficientNetv2 was applied for VPI prediction with HRCT images meticulously annotated for AI model training and validation.Of the 472 lung cancer cases (500 CT images) studied, the AI algorithm successfully identified tumors, with YOLOv4.0 accurately localizing tumors in 98% of the test images. In the EfficientNet v2-M analysis, the receiver operating characteristic curve exhibited an area under the curve of 0.78. It demonstrated powerful diagnostic performance with a sensitivity, specificity, and precision of 76.4% in VPI prediction.AI is a promising tool for improving the diagnostic accuracy of VPI for NSCLC. Furthermore, incorporating AI into the diagnostic workflow is advocated because of its potential to improve the accuracy of preoperative diagnosis and patient outcomes in NSCLC.Conclusion: This study aimed to assess the efficiency of artificial intelligence (AI) in the detection of visceral pleural invasion (VPI) of lung cancer using high-resolution computed tomography (HRCT) images, which is challenging for experts because of its significance in T-classification and lymph node metastasis prediction.This retrospective analysis was conducted on preoperative HRCT images of 472 patients with stage I non-small cell lung cancer (NSCLC), focusing on lesions adjacent to the pleura to predict VPI. YOLOv4.0 was utilized for tumor localization, and EfficientNetv2 was applied for VPI prediction with HRCT images meticulously annotated for AI model training and validation.Of the 472 lung cancer cases (500 CT images) studied, the AI algorithm successfully identified tumors, with YOLOv4.0 accurately localizing tumors in 98% of the test images. In the EfficientNet v2-M analysis, the receiver operating characteristic curve exhibited an area under the curve of 0.78. It demonstrated powerful diagnostic performance with a sensitivity, specificity, and precision of 76.4% in VPI prediction.AI is a promising tool for improving the diagnostic accuracy of VPI for NSCLC. Furthermore, incorporating AI into the diagnostic workflow is advocated because of its potential to improve the accuracy of preoperative diagnosis and patient outcomes in NSCLC.Graphical abstract: This study aimed to assess the efficiency of artificial intelligence (AI) in the detection of visceral pleural invasion (VPI) of lung cancer using high-resolution computed tomography (HRCT) images, which is challenging for experts because of its significance in T-classification and lymph node metastasis prediction.This retrospective analysis was conducted on preoperative HRCT images of 472 patients with stage I non-small cell lung cancer (NSCLC), focusing on lesions adjacent to the pleura to predict VPI. YOLOv4.0 was utilized for tumor localization, and EfficientNetv2 was applied for VPI prediction with HRCT images meticulously annotated for AI model training and validation.Of the 472 lung cancer cases (500 CT images) studied, the AI algorithm successfully identified tumors, with YOLOv4.0 accurately localizing tumors in 98% of the test images. In the EfficientNet v2-M analysis, the receiver operating characteristic curve exhibited an area under the curve of 0.78. It demonstrated powerful diagnostic performance with a sensitivity, specificity, and precision of 76.4% in VPI prediction.AI is a promising tool for improving the diagnostic accuracy of VPI for NSCLC. Furthermore, incorporating AI into the diagnostic workflow is advocated because of its potential to improve the accuracy of preoperative diagnosis and patient outcomes in NSCLC. [ABSTRACT FROM AUTHOR]

We have developed and integrated a mobility-enhanced FET and a wakeup-free ferroelectric (FE) capacitor using Sn-doped InGaZnO (IGZTO) and demonstrated 1T1C FeRAM cell operation for 3-D embedded RAM application. IGZTO FET can achieve >20 cm2/V $\cdot $ s mobility with an ultrathin channel, which is $2\times $ higher than InGaZnO (IGZO) FET. The physics of mobility enhancement in oxide semiconductor FET with IGZTO channel is investigated by both experimental and simulation methods. The FE capacitor with large remanent polarization and low-temperature process at 400 °C is achieved. We have also studied the impact of thin-film access transistors on 1T1C cell operation with gate voltage dependence and capacitor size dependence. SPICE simulation is used for an extremely scaled device that achieves ~ns operation. The proposed memory technology will enable high-density and energy-efficient computing by the proximity of processor core and memory in monolithic 3-D integration. [ABSTRACT FROM AUTHOR]

We describe a boron (B) transporter, Os BOR1, in rice (Oryza sativa). Os BOR1 is a plasma membrane-localized efflux transporter of B and is required for normal growth of rice plants under conditions of limited B supply (referred to as -B). Disruption of Os BOR1 reduced B uptake and xylem loading of B. The accumulation of Os BOR1 transcripts was higher in roots than that in shoots and was not affected by B deprivation; however, Os BOR1 was detected in the roots of wild-type plants under -B conditions, but not under normal conditions, suggesting regulation of protein accumulation in response to B nutrition. Interestingly, tissue specificity of Os BOR1 expression is affected by B treatment. Transgenic rice plants containing an Os BOR1 promoter-β-glucuronidase (GUS) fusion construct grown with a normal B supply showed the strongest GUS activity in the steles, whereas after 3 d of -B treatment, GUS activity was elevated in the exodermis. After 6 d of -B treatment, GUS activity was again strong in the stele. Our results demonstrate that Os BOR1 is required both for efficient B uptake and for xylem loading of B. Possible roles of the temporal changes in tissue-specific patterns of Os BOR1 expression in response to B condition are discussed. [ABSTRACT FROM AUTHOR]

The roles of three membrane proteins, BOR1, DUR3, and FPS1, in boron (B) transport in yeast were examined. The boron concentration in yeast cells lacking BOR1 was elevated upon exposure to 90 mM boric acid, whereas cells lacking DUR3 or FPS1 showed lower boron concentrations. Compared with control cells, cells overexpressing BOR1 or FPS1 had a lower boron concentration, and cells overexpressing DUR3 had a higher boron concentration. These results suggest that, in addition to the efflux boron transporter BOR1, DUR3 and FPS1 play important roles in regulating the cellular boron concentration. Analysis of the yeast transformants for tolerance to a high boric acid concentration revealed an apparent negative correlation between the protoplasmic boron concentration and the degree of tolerance to a high external boron concentration. Thus, BOR1, DUR3, and FPS1 appear to be involved in tolerance to boric acid and the maintenance of the protoplasmic boron concentration. [ABSTRACT FROM AUTHOR]

The article discusses the results of a study investigating the cDNAs of the plant Arabidopsis thaliana that can confer yeast boric acid tolerance. Five clones conferring tolerance to high boric acid content of soil were identified as a polyadenylate-binding protein, a ribosomal small subunit protein, an RNA-binding protein, and two Myb transcription factors. The expression of these five genes also conferred boric acid tolerance on wild-type yeast.

We have investigated ferroelectric phase formation of Si-doped HfO2 through nucleation and phase transition in the thermal process by first-principles simulation. For the nucleation process from amorphous HfO2 in the thin film during thermal annealing, the tetragonal phase can be thermodynamically preferred with the effects of dopant and surface energy and temperature for which entropy is directly calculated from phonon spectrum calculations. During cooling down, the diffusionless phase transition from the tetragonal to ferroelectric phase takes place by atomic displacement and the transition to the monoclinic phase is suppressed by the high kinetic activation barrier. The phase transition process from the tetragonal phase to the ferroelectric phase is directly confirmed by ab initio molecular-dynamics simulation. [ABSTRACT FROM AUTHOR]

We have monolithically integrated resistance random access memory (RRAM) array with oxide semiconductor channel access transistor in 3-D stack, achieved uniform memory characteristics of 1T1R cells at each layer, and demonstrated basic functionality of XNOR operation as in-memory computing for binary neural network (BNN) artificial intelligence (AI) applications. The integrated TiN/Ti/HfO2/Ti stack RRAM shows high on/off ratio with stable retention and endurance properties. The indium gallium zinc oxide (IGZO) channel field-effect transistor (FET) works as an access transistor, which realized the low-temperature process, high mobility, and high drive current for RRAM. With the peripheral circuit, we demonstrate the XNOR operation using a pair of 1T1R cells. The impact of RRAM bit error rate on neural network is also investigated, which indicates the property of error-resilience in BNN. The 3-D neural network built by this architecture has high potential to enable area-efficient, low-power, and low-latency computing. [ABSTRACT FROM AUTHOR]

A unique feature of the extremely long-range-extended blockade regime with its shape of a long stick, where the Coulomb blockade oscillation and negative differential conductance peak-positions can be systematically and precisely modulated for both extremely-wide VG and VD ranges, was clearly observed in a room-temperature-operating silicon single hole transistor. These results originate from the large quantum level spacing, large tunnel-barrier height, small tunnel-barrier curvature, small bias-induced barrier modulation, and large voltage gain, attributing to the formation of an ultrasmall dot in the gently sloped tunnel barriers along the [100] Si nanowire channel having the large subband modulation. [ABSTRACT FROM AUTHOR]

In this paper, we have developed multilayer bonding technology to stack complementary metal–oxide semiconductor (CMOS) circuits. The steps include repeated embedding of gold (Au) electrodes, hybrid bonding of Au and SiO2 on a silicon-on-insulator (SOI) substrate using surface activation with O2 plasma, and subsequent elimination of the Si substrate. Furthermore, the characteristics of Au/SiO2 hybrid bonding via O2 plasma are tested with the fabrication of a triple-stacked daisy-chain test device using 3- $\mu \text{m}$ -diameter Au electrodes at a pitch of $6~\mu \text{m}$. When the surface is activated using O2 plasma before bonding, the bonding strength increases approximately four times stronger than that when the surface activation is performed with sequential plasmas of Ar and O2. This additional strength ensures that the bonded interface remains intact while the layers are stacked. A prototype device is manufactured with alignment errors of approximately $0.4~\mu \text{m}$ at the center and approximately 1 $\mu \text{m}$ at the corners. No voids are seen in the two bonded interfaces, and more than 984 000 Au contacts are produced, each having an average resistance of 92.8 $\text{m}\Omega $. These results indicate that the proposed multilayer stacking technology is promising for developing high-performance 3-D integrated circuits, 3-D integrated CMOS image sensors, and microelectromechanical systems based on SOI substrates. [ABSTRACT FROM AUTHOR]

We have studied the surface cleaning of Sb-based compound semiconductors using HF, NH4OH, and HCl cleans and the metal-oxide-semiconductor (MOS) capacitors fabricated subsequently. GaSb, InGaSb, and AlGaSb surfaces are investigated using low-energy radiation from the synchrotron. Capacitance-voltage (C-V) and photoluminescence measurements are carried out on capacitors made with Al2O3 from atomic layer deposition and corroborated with the results from synchrotron spectroscopy. Excellent C-V characteristics with a mid-band-gap interface state density of 3 × 1011/cm2eV are obtained on samples with the HCl clean. This is consistent with the finding that only the HCl acid clean is able to remove the native oxides present on GaSb and InGaSb surfaces, and produce clean and stable surfaces suitable for MOSFET development. Complete removal of AlOx on the AlGaSb surface was not possible using chemical cleaning. Termination of AlGaSb with two monolayers of GaSb is proposed as a solution. [ABSTRACT FROM AUTHOR]

We have developed a quarter video graphics array (QVGA) digital pixel image sensor by using the 3-D integration technology. The pulse-frequency modulation (PFM) analog-to-digital converter (ADC) operates as a digital pixel, which overcomes the signal saturation due to the full well capacity of the photodiode (PD). We have also newly designed a PFM-ADC for pixels with a pinned PD and a floating diffusion to comply with the CMOS image sensor process used to attain high sensitivity and low noise. PDs, comparators, logic circuits, and counters are integrated into two silicon-on-insulator layers by pixel-wise 3-D integration with gold electrodes with a ${5}~\mu \text{m}$ diameter, thereby achieving a QVGA resolution for a 20-mm square chip in the 0.18- and 0.2- $\mu \text{m}$ process nodes. The developed sensor exhibits both the excellent linearity and a wide-dynamic range of more than 96 dB. Video images with a high bit depth of 16 bit are also obtained to demonstrate the superior image sensing, capable of capturing the real world at high fidelity. [ABSTRACT FROM AUTHOR]

The data stored in a static random access memory (SRAM) immediately after power-up is of practical interest for some applications, such as SRAM physical unclonable functions. In this paper, measurements of SRAM cell power-up state (i.e., whether the cell is storing 0 or 1 after the power supply is turned on) using an addressable cell array test structure are reported. The test structure provides direct access to individual transistor characteristics of many SRAM cells, which would facilitate the characterization of SRAM power-up behavior. Methods and considerations necessary for reliable and stable power-up state characterization using the test structure will be discussed and demonstrated. [ABSTRACT FROM PUBLISHER]

Four write stability metrics for the characterization of six-transistor SRAM cells were experimentally evaluated and compared at low supply voltage ( V\mathrm {DD}) . A silicon-on-thin-BOX technology with reduced body doping was used to achieve low voltage operation. It was confirmed that both bitline and wordline methods are preferable in that they yield metrics that follow normal distributions, which is practically beneficial for the yield estimation. On the contrary, different from at high V\mathrm {DD} , both write static noise margin from write butterfly curve and write N -curve current ( IW) exhibit non-normal probability distributions. The origins of the non-normality are analyzed in detail. [ABSTRACT FROM AUTHOR]

We have developed for the first time a 3-D integrated CMOS image sensor with pixel-parallel analog-to-digital converters (ADCs). Photodiode (PD) and inverter layers are prepared on separate silicon-on-insulator layers and directly bonded with damascened Au electrodes. The handle layer is then removed by grinding and XeF2 vapor phase etching to expose the PD surface. The developed process is suitable for pixelwise interconnection because it allows the damascened Au electrodes to be 1 \mu \textm in diameter or less. An ADC circuit is designed based on pulse frequency modulation where pulses are generated proportional to the illumination intensity, and contains a PD, inverters, a reset transistor, and counters. A prototype 3-D integrated CMOS image sensor is also developed with 64 pixels, which acquires video images without pixel defects. A wide dynamic range of >80 dB is confirmed for the incident light intensity. The experimental results demonstrate the feasibility of pixel-level 3-D integration for high-performance CMOS image sensors. [ABSTRACT FROM AUTHOR]

We demonstrate self-aligned fully-depleted 20-nm-thick In0.53Ga0.47As-channel MOSFETs using CMOS-compatible device structures and manufacturable process flows. These devices consist of self-aligned source/drain extensions and self-aligned raised source/drain with low sheet resistance of 360 and \(115~\Omega \) /sq, respectively. We demonstrate short-channel MOSFETs with gate lengths \(L_{G}\) down to 30 nm, low series resistance \(R_{\mathrm {EXT}}=375~\Omega \cdot \mu \) m, and high peak saturation transconductance \(G_{\mathrm {MSAT}}=1275~\mu \) S/ \(\mu \) m at \(L_{G} =50\) nm and drain bias \(V_{\mathrm {DS}} =0.5\) V. We obtain long-channel capacitive inversion thickness \(T_{\mathrm {INV}}= 2.3\) nm and effective mobility \(\mu _{\mathrm {EFF}} =650\) cm \(^{2}\vphantom {\Big (}\) /Vs at sheet carrier density \(N_{\mathit {S}} = 5 \times 10^{12}\) cm \(^{\mathrm {-2}}\) . Finally, using a calibrated quasi-ballistic FET model, we argue that for \(L_{G} \le 20\) nm, \(\mu _{\mathrm {EFF}}\approx 1000\) cm \(^{2}\) /Vs will lead to short-channel MOSFETs operating within 10% of the ballistic limit. Thus, our III–V processes and device structures are well-suited for future generations of high-performance CMOS applications at short gate lengths and tight gate pitches. [ABSTRACT FROM AUTHOR]

Through a combination of electrical measurements, technology computer-aided design simulations, and wafer bending experiments, the effect of elastic stress relaxation on the layout dependence of \Si1-x\Gex\-channel p-channel field-effect transistors (pFETs) is studied. This work focuses on scaling of the transistor width W, the active-area length (length of diffusion, LOD) for isolated transistors, and poly-to-poly length LP/P of nested configurations. A strong narrow-width current enhancement is reported, even for relatively large widths, above 100 nm. On the other hand, the layout dependence on LOD or LP/P is also predicted but only for aggressively scaled layouts (LOD or LP/P below 100 nm). W and LP/P scaling lead to current enhancement, whereas LOD scaling is expected to degrade performance. No significant dependence of short-channel threshold voltage on W, LOD, or LP/P was observed. This study indicates that, as higher germanium concentrations of the channel lead to more layout dependence, this concentration may need to be optimized carefully to combine high channel mobility with limited added design complexity. Moreover, the channel thickness should be kept as thin as possible, as layout dependence is enhanced for thicker channels. [ABSTRACT FROM PUBLISHER]

Boron deficiency hampers the productivity of 132 crops in more than 80 countries. Boron is essential in higher plants primarily for maintaining the integrity of cell walls and is also beneficial and might be essential in animals and in yeast. Understanding the molecular mechanism(s) of boron transport is crucial for alleviating boron deficiency. Here we describe the molecular identification of boron transporters in biological systems. The Arabidopsis thaliana mutant bor1-1 is sensitive to boron deficiency. Uptake studies indicated that xylem loading is the key step for boron accumulation in shoots with a low external boron supply and that the bor1-1 mutant is defective in this process. Positional cloning identified BOR1 as a membrane protein with homology to bicarbonate transporters in animals. Moreover, a fusion protein of BOR1 and green fluorescent protein (GFP) localized to the plasma membrane in transformed cells. The promoter of BOR1 drove GFP expression in root pericycle cells. When expressed in yeast, BOR1 decreased boron concentrations in cells. We show here that BOR1 is an efflux-type boron transporter for xylem loading and is essential for protecting shoots from boron deficiency. [ABSTRACT FROM AUTHOR]

We demonstrate the effect of uniaxial tensile and compressive strain in Ge p-i-n photodiode integrated on Si using four-point bending structures. Responsivity at 1550 nm is increased from 0.67 to 0.75 A/W by tensile strain in the <110> direction while for compressive strain it decreases from 0.67 to 0.477 A/W. These uniaxial tensile and compressive strains also effectively result in shifts of the absorption spectra toward longer and shorter wavelength as they reduce or increase the direct bandgap energy of the Ge layer, respectively. [ABSTRACT FROM AUTHOR]

The surface cleaning of InGaAs and InAlAs is studied using synchrotron radiation photoelectron spectroscopy. Thermal annealing at 400 °C cannot completely remove the native oxides from those surfaces. Elemental arsenic buildup is observed on both surfaces after acid treatment using HCl, HF, or H2SO4 solution, which is similar to acid-cleaned GaAs surface. Cleaned InGaAs surface is oxide-free but small amount of aluminum oxide remains on cleaned InAlAs surface. The common chemical reactions between III-As semiconductors and acid solutions are identified and are found to be dominated by arsenic chemistry. [ABSTRACT FROM AUTHOR]