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A comprehensive study of dielectric modulated (DM) drift regions for power devices is presented in this paper. The performance of this structure is theoretically analyzed and compared with both conventional and superjunction (SJ) structures. In this paper, an analytical model for DM drift regions with cylindrical cells is proposed and compared with linear cells. An optimal tradeoff between breakdown voltage (BV) and specific ON-resistance ( R\scriptscriptstyle ON,sp) is obtained by a methodology developed in this paper. 3-D simulations of DM structures with hexagonal cells approximated by cylindrical cells are conducted to verify the analytical model. Optimal BV– R\scriptscriptstyle ON,sp tradeoffs for devices with conventional and SJ drift regions are also obtained through the same methodology and verified by 3-D simulations. Static characteristics of these three different drift region structures in both Si and SiC power devices are compared. [ABSTRACT FROM AUTHOR]

A comprehensive study on the dielectric modulated (DM) drift region for power devices is presented in this paper. The performance of this drift region structure is theoretically analyzed and compared with other two structures: conventional and superjunction. In this paper, a study is focused on switching performance. The C – V relationships during switching are analytically derived, and the depletion widths predicted by the proposed analytical model agree well with simulation in a wide reverse bias region. The switching energy loss is evaluated based on the analytical model and its accuracy is verified by 2-D simulations. An effective depletion charge QD is defined as E\mathrm {loss} / breakdown voltage (BV), from which a figure of merit (FOM) of R\mathrm{\scriptscriptstyle ON,\mathrm {sp}}{}^\ast QD is proposed to compare the performances of these different drift region structures, considering both the conduction and switching losses. The discussions in part I on Si and silicon carbide device structures are extended in part II to include FOMs. It is found that the DM drift region structures show better R\mathrm{\scriptscriptstyle ON,\mathrm {sp}} -BV tradeoffs compared with the conventional structures, but slighter inferior FOMs. However, DM structures are still attractive for applications, where switching loss is less critical than the conduction loss, such as low frequency or soft switching. [ABSTRACT FROM PUBLISHER]

As one of the two-dimensional (2-D) transition metal dichalcogenides, atomically thin molybdenum disulfide (MoS 2 ) has attracted significant attention and research interests for micro and nanoelectronic applications. Significant efforts have been made to develop different approaches in order to obtain atomic layer MoS 2 , such as exfoliation, chemical synthesis, and physical or chemical vapor deposition (CVD) processes. In this paper, we report a hydrogen-free and promoter-free CVD growth to synthesize large-area MoS 2 atomic layers. A variety of techniques including optical microscopy (OM), atomic force microscopy (AFM), photoluminescence (PL) mapping, Raman and x-ray photoelectron spectroscopy (XPS), high resolution electron microscopy (HREM) and scanning transmission electron microscopy (STEM) were applied to characterize the film quality, uniformity and layer numbers. High quality centimeter-sized MoS 2 atomic layers were demonstrated, which form a foundation to develop wafer-sized material platform for device fabrication and production. [ABSTRACT FROM AUTHOR]

The paper is mainly to explore the automated music composition experiences for the students in the high grades of elementary school who are unfamiliar with the professional music theory. The proposed Automated Composition for Music Education (ACME) software was developed to help the students to compose the rhythm and melody themselves, while chord configuration and arrangement are automatically generated. Subsequently, sixth-year students of a non-experimental school were recruited to use the software for the completion of its development. Analysis of learning effectiveness at the reaction level, analysis of learning-level learning effectiveness, correlation analysis of the reaction- and learning-levels learning effectiveness has been performed with a significant result. The correlations between each component of learning effectiveness at the reaction and learning levels were also found. Finally the students in the experimental group using the ACME teaching materials showed a better learning effectiveness at both reaction level and learning level, than those of the students in the comparison group. [ABSTRACT FROM AUTHOR]

AlGaN/GaN dual metal Schottky barrier diodes (SBD) are demonstrated on a silicon substrate. The anode is composed of two metals with different work functions to achieve a better trade-off between the forward and the reverse characteristics. The low work function metal Ti reduces the turn-on voltage and the high work function metal Ni at the edge of the anode reduces the reverse leakage current and maintains the breakdown voltage. The turn-on voltage of the Ni-SBD is reduced from 1.47 V to 0.57 V by employing the dual metal anode, and the breakdown voltages are virtually unaffected. [ABSTRACT FROM AUTHOR]

In this paper, a comparison of different techniques for SiC high-voltage devices is performed using numerical simulations. In particular, the method of counter doping (CD) introduced in the junction termination extension (JTE) region to create a multizone termination effect is investigated. Simulation shows that compared with the other edge termination techniques, CD-JTE greatly reduces the sensitivity of breakdown voltage (BV) to JTE doses and surface charges. The multizone CD-JTE with outer rings shows that for a 30- \mu m thick epi-layer, 90% of the theoretical BV is achievable with a wide tolerance of 11\,\times \,10^{\mathrm {12}} /cm ^{2} to the JTE dose and 85% of the theoretical BV with an increased tolerance of 6.19\times 10^\mathrm 12 /cm ^2 to the positive surface charges, both superior to other JTE structures investigated in this paper. [ABSTRACT FROM AUTHOR]

Abstract: With the proliferation of wireless sensor network technologies, the context-aware applications of smart environments have become more and more popular. However, time-consuming and labor-intensive works hamper the development of smart building applications. Therefore, application developers need the proper software platforms to efficiently design the applications. Much research currently proposed the design approaches based on low-level concerns and the real-world deployments based on high-level programming abstraction are rare. Accordingly, the pressing issue is how to offer the easy-to-use tools with acceptable performance to rapidly and easily design the application scenarios for non-technical application users. Therefore, this study focuses on the application-layer simulation to propose a Visualization System of Context-aware Application Scenario Planning (VS-CaSP) for assisting non-technical developers and end-users in rapidly and easily designing the application scenario of smart buildings and in performing the acceptable and predictable simulation and evaluation. VS-CaSp applies rule-based and 3D visualization techniques to offer a 3D authoring environment integrated with real Zigbee sensor devices, where designers are able to rapidly construct immersive 3D buildings and easily plan the context-aware application scenario via GUI tool based on proposed three-tier rule hierarchy, to visually simulate and verify the planned scenario via virtual and real sensor devices, and to repeatedly modify the control strategies to enhance the deployment effectiveness. The experimental results show that VS-CaSP is easy to use for the support of quickly designing smart building applications, but not professional enough for developments of 3D modeling, animation, and rule expression. Accordingly, it is workable and expected to prove beneficial to non-technical users. [Copyright &y& Elsevier]

Abstract: The goal of this research is to investigate the correlation of reverse characteristics of Schottky barrier diodes (SBDs) and surface morphological defects on 4° (off-axis) carbon (C) face, 4° and 8° silicon (Si) face 4H-SiC. Different dimensions of SBDs with boron-implanted edge terminations are fabricated on 4° C-face, 4° and 8° Si-face 4H-SiC samples. The ideality factor for these three samples is about 1.1. Average breakdown voltages of 4° Si-face 4H-SiC SBDs are higher than the other two samples, particularly for large size SBDs. Breakdown voltages of 1500 and 2000μm 4° Si-face SBDs can reach over 1000V. This value is about two times higher than the other two samples, though the root-mean-square (RMS) roughness of 4° Si-face samples obtained from atomic force microscopy (AFM) is 3.5nm. The yield of 1500 and 2000μm 4° Si-face 4H-SiC SBDs with a breakdown voltage over 1000V is more than 50%, much higher than the other two samples. [Copyright &y& Elsevier]

A good magnetic field sensor should exhibit high sensitivity, low power consumption, and low output offset to accurately detect small fields. In this work, the high sensitivity in magnetoresistance variation (ΔR) is achieved by the AlGaN/GaN fin-shaped high electron mobility structure, in comparison to that of planar structures. A physical based analysis is presented to describe the influence of the fin width dimension on the ΔR dependency under magnetic fields. The sensitivity is expressed as a function of geometric parameters, electron mobility, and two-dimensional electron sheet density, with relaxation of polarization, shoulder density distribution, and sidewall trapped charges considered. Devices were fabricated, and a high sensitivity is observed in laboratory measurements on devices at narrower fin widths. At the fin width of 50 nm, the measured device has a sensitivity of 0.76 Ω/μΤ2 at the magnetic flux of 85 μΤ. The sensor's power consumption is as low as 48 μW, and the minimum magnetic flux detectable is at 20 μΤ. [ABSTRACT FROM AUTHOR]

Background: Helicobacter pylori (H. pylori) infection can induce individual inflammatory and immune reactions which associated with extra-digestive disorders. Our aim is to investigate the association between H. pylori infection and bone mineral density.Methods: This retrospective cross-sectional study was performed by using the data from the health examination database in a medical center of southern Taiwan in 2013. We investigated the relationship between sex, age, body mass index (BMI), waist circumstance, lipid profile, H. pylori infection, the findings of upper gastrointestinal endoscopy and bone mineral density (BMD). Because of nonrandomized assignment and strong confounding effect of age on BMD, the 1:1 propensity score match was applied for age adjustment. The simple and multiple stepwise logistic regression analysis were performed to assess the risk factors of decreased BMD in these well-balanced pairs of participants.Results: Of the 867 subjects in final analysis with the mean age of 55.9 ± 11.3 years, 381 (43.9%) subjects had H. pylori infection, and 556 (64.1%) subjects had decreased BMD. In decreased BMD group, the portion of woman was higher than a normal BMD group (37.2% versus 29.6%, P = 0.023), the age was significantly older (59.4 ± 9.8 versus 49.8 ± 11.3, p < 0.001) and BMI was significantly lower (24.7 ± 3.5 versus 25.4 ± 3.7, p = 0.006) than the normal BMD group. The prevalence of H. pylori infection was 39.9% and 46.2% in the normal BMD group and the decreased BMD group respectively (P = 0.071). The multivariate analysis which was used for these possible risk factors showed that only advanced age (OR 1.09, 95% CI 1.08-1.11, P < 0.001), and low BMI (OR 0.91, 95% CI 0.87-0.95, P < 0.001) were independently significantly associated with decreased BMD in this nonrandomized study. In the propensity score-matched participants, the multiple stepwise logistic regression analysis revealed H. pylori infection (OR 1.62, 95% CI 1.12-2.35, P = 0.011) and low BMI (OR 0.92, 95% CI 0.87-0.97, P = 0.001) were independently significantly associated with decreased BMD.Conclusions: H. pylori infection and low BMI were independently significantly associated with decreased BMD in selected propensity score-matched populations after age adjustment. [ABSTRACT FROM AUTHOR]

The paper reports on the investigation of honey as the electrolyte gate dielectrics of graphene field effect transistors. Transfer and output characteristics of graphene transistors were collected at room temperature and 40 °C under open air. Typical behaviors such as Dirac neutrality point and linear relation of drain current with drain-source voltage at low field and various gate bias voltages were achieved. In addition, cleaning and reapplication of honey on transistors only show slight changes in those characteristics. [ABSTRACT FROM AUTHOR]

In this letter, the suppression of dynamic on-state resistance (RON) degradation for faster dynamic RON recovery is achieved by the multimesa-channel (MMC) structure in AlGaN/GaN high electron mobility transistors. The measurement results are discussed with the physical mechanisms investigated. The initial transient RON degradation is reduced in the MMC structure, resulting from the lower peak electric field around the drain-side gate edge in the trigate structure compared to that in a planar device. The faster dynamic RON recovery in MMC devices is attributed to the quick emission of electrons at sidewall traps of shallower energy levels. The energy levels of dominant traps at the sidewall and top interfaces are found to be 0.26 eV and 0.37 eV below the conduction band edge, respectively, verified by Technology Computer Aided Design simulations in agreement with the measurement data. [ABSTRACT FROM AUTHOR]

In this paper, an observation of drain current instability on p-GaN gate AlGaN/GaN HEMTs is reported. Contrary to the Schottky gate AlGaN/GaN HEMTs, which show stable and consistent Id – Vd curves under different pulsed conditions, the Id – Vd curves for p-GaN gate AlGaN/GaN HEMTs show a dispersion in the saturation region under the same pulse conditions, which cannot be explained by the trapping of electrons in the material. A model considering the trapping of holes in the p-GaN gate under different gate and drain biases is proposed to explain this new phenomenon. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC), a wide bandgap semiconductor, is more desirable over conventional silicon (Si) to satisfy the increasing demands for microelectromechanical system (MEMS) to operate in harsh environments due to the excellent physical, mechanical and chemical inertness. Research in MEMS devices based on single or polycrystalline SiC on Si or SOI substrate, such as 3C-SiC polytype, have been widely carried out. Another promising candidate is “all”-SiC, i.e., homoepitaxial single crystal SiC layer on single-crystal SiC substrate, such as 4H and 6H-SiC polytypes. They truly exploit the superior material properties of SiC and provide advantages for MEMS devices to operate in hostile conditions. In this work, 4H-SiC MEMS actuators in cantilever and bridge configurations were fabricated by a surface micromachining process, and their dynamic responses were characterized to determine Young’s modulus of 4H-SiC and frequency performance. Resonant frequencies of 1.208 MHz from cantilever and 1.338 MHz from bridge actuators were achieved. These high frequency operation capabilities are particular interesting for ultrafast and high resolution sensors and actuators. [ABSTRACT FROM AUTHOR]

A new automated permuting capacitor device (APCD) for calibration of inductive voltage dividers (IVDs) with four-terminal-pair definition was designed and tested. The permuting capacitors composed of 11-SMD capacitors were housed in a bulk metal in a symmetrical arrangement. Thus, the APCD is compact and the temperature of the APCD could be controlled within several mKs. Using coaxial microwave switches, the APCD was permuted quickly and automatically using electrical signals during the calibration process. This prevented the APCD from being thermally perturbed by manual operation. Owing to the improved stability of the device, the effects of stray capacitance and voltage coefficient of the APCD were evaluated accurately. The calibration of an IVD using the permuting capacitor method with this APCD in the frequency range 1–2 kHz with accuracy comparable with that of the straddling method is presented in this paper. [ABSTRACT FROM PUBLISHER]

Design and fabrication of 4H–SiC lateral high-voltage devices on semi-insulating substrates based on the charge compensation principle have been investigated in this work. In the simulation, field plates are critical in relieving the electric field crowding at junction corners at high reverse biases. By incorporating field plates with proper lengths, the breakdown voltage (BV) of a single-zone reduced-surface-field (RESURF) device with a 100- \mu\m drift region can be improved from 3360 to 5880 V. The BV can be further enhanced to 8000 V by using a two-zone RESURF structure. The reduction in BV by 10% charge imbalance variation is also improved from 49% for a single-zone structure to 36% for a two-zone structure. Simulation also shows that oxide charges and other surface charges will offset the optimized charge imbalance conditions and, therefore, should be considered in design if the amount is significant. A 4H–SiC JFET with a two-zone RESURF region was fabricated to demonstrate the advantages of lateral devices based on these concepts. The fabricated lateral 4H–SiC JFET has a BV of 4200 V and a specific on -resistance of 454 \m\Omega\cdot \cm^2. The figure of merit is as high as 38.8 \MW/cm^2. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we report on a novel surface micromachining process technology for the fabrication of microelectromechanical systems in SiC. Single-crystal SiC suspended microstructures were fabricated using a dopant-selective photoelectrochemical etching process, which allows for undercutting the p-SiC layer by rapid lateral etching of the underlying n-SiC substrate. The selective etching was achieved by applying a bias which employs the different flat-band potentials of n-SiC and p-SiC in the KOH solution. Single-crystal SiC MEMS developed in this study fully exploits the superior mechanical and biocompatible properties of SiC and has the capability of monolithic integration with electron devices and circuits, and therefore, is promising for sensing and actuating operations in biomedical, high-temperature and harsh environments. [ABSTRACT FROM AUTHOR]

Abstract: SiO2 encapsulation layer was studied for aluminum (Al) and phosphorus (P) implant activation anneal in 4H-SiC. Both Al- and P+ implantation were carried out at 650°C followed by activation anneal at 1400°C to 1500°C. X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and four-point-probe (FPP) measurements were performed to examine surface stoichiometry, roughness, and sheet resistance of the implanted SiC regions. The effect of using SiO2 encapsulation layer for Al implant activation on the performance of 4H-SiC p-i-n diodes with both p-type active region and JTE region formed by Al implantation was also investigated. Forward and reverse characteristics including saturation current density J 0 , ideality factor η, reverser leakage current density J L and threshold breakdown voltage V BR have been extracted. The results show that SiO2 encapsulation effectively protects the SiC surface during high temperature implant activation for both Al- and P+. [ABSTRACT FROM AUTHOR]

This work demonstrates a trench isolated lateral double-implanted MOSFET (LDMOS) on Si-face in 4H-silicon carbide (SiC). A device $\vphantom {_{\int _{}}}$ where ${L}_{\textit {ch}} = 0.8\,\,\mu \text{m}$ and ${L}_{d} = 12\,\,\mu \text{m}$ shows an ${R}_{ \mathrm{\scriptscriptstyle ON},\text {sp}}$ of 22.9 $\text{m}\Omega $ cm2 at a ${V}_{\text {GS}}$ of 20 V and a breakdown voltage (BV) of 1100 V, corresponding to a high BV2/ ${R}_{ \mathrm{\scriptscriptstyle ON},\text {sp}}$ of 55.5 MW/cm2. Devices that have different ${L}_{\text {ch}}$ , ${L}_{\text {JFET}}$ , ${L}_{d}$ , and P-top dose values are measured in order to investigate the effects of geometry on the static performance. Operations at 150 °C are measured to evaluate the temperature performance. Gate charge waveforms are also measured in order to include the switching performance in the evaluation. The ${R}_{ \mathrm{\scriptscriptstyle ON}} \times {Q}_{G}$ and ${R}_{ \mathrm{\scriptscriptstyle ON}} \times {Q}_{\text {GD}}$ values are calculated as 17.7 and $9.0~\Omega $ nC, respectively, which are promising for power-integrated circuit applications. [ABSTRACT FROM AUTHOR]

Purpose: Constipation is a common and distressing symptom for patients with advanced cancer. Few reports have focused on the symptoms of constipation in patients with advanced cancer. The aim of this study was to investigate the effect of a short-term acupressure intervention on patients with advanced cancer.Methods: This study used a non-randomized, pre-post study design to assess the effect of acupressure intervention. A total of 30 patients with advanced cancer were recruited from the hospice unit of a medical center in southern Taiwan. In addition to routine care, patients in the intervention group received an 8-min acupressure treatment daily for 3 consecutive days. Three acupoints were used in this study: Zhongwan (CV12), Guanyuan (CV4), and Tianshu (ST25). Analysis of covariance was used to compare the differences in symptoms of constipation between the two groups, adjusted for baseline values. Effect sizes were calculated using partial eta squared (η2).Results: Significant improvements in symptoms of constipation (partial η2 = 0.40, p < 0.001 for straining during defecation; partial η2 = 0.30, p = 0.002 for hard stools; partial η2 = 0.42, p < 0.001 for sensation of incomplete evacuation; and partial η2 = 0.29, p = 0.002 for sensation of anorectal obstruction), Bristol stool form scale scores (partial η2 = 0.40, p < 0.001), comfort levels during defecation (partial η2 = 0.82, p < 0.001), and colonic motility (partial η2 = 0.85, p < 0.001) were observed in patients receiving acupressure intervention compared with the controls.Conclusions: Findings from this study indicated that short-term acupressure was effective in alleviating symptoms of constipation among patients with advanced cancer. Further, randomized controlled trials are warranted to confirm the results. [ABSTRACT FROM AUTHOR]

• Quasi-vertical Schottky barrier diodes were fabricated on GaN on Si substrate. • The diodes exhibited ultra-low turn on voltage of 0.23 V and ideality factor of 1.02 being close to the ideal value. • Schottky barrier height was extracted from both current–voltage and capacitance–voltage curves. • Experimental current–voltage characteristics are consistent with the simulation results obtained using Silvaco TCAD software. • Temperature dependent reverse leakage current is attributed to variable range hopping mechanisms through dislocations. Quasi-vertical Schottky Barrier Diodes (SBDs) with near to ideal turn-on voltage and ideality factor (n) of 1.02, were fabricated on a GaN on Si substrate. The average turn-on voltage and on-resistance values were found to be 0.23 ± 0.005 V (at 1 A/cm2) and 1.76 ± 0.11 mΩcm2, respectively with diode series resistance of 11 Ω. The analysis of the current–voltage curve revealed a temperature-independent barrier height, however the capacitance–voltage method showed a negative temperature coefficient. This discrepancy is discussed in the paper. Variable range hopping through dislocations is shown to be the dominant reverse current leakage mechanisms identified in the fabricated diode, with a characteristic temperature, T 0 of 2 × 1010 K. [ABSTRACT FROM AUTHOR]

Highlights • Y 2 O 3 /Al 2 O 3 stacking films on p-type 4H-SiC were studied for the first time. • High-k Y 2 O 3 /Al 2 O 3 provides thicker film with equivalent capacitance. • Y 2 O 3 /Al 2 O 3 exploits the high breakdown strength of 4H-SiC in MOSFET. • Post deposition annealing affects properties of Y 2 O 3 /Al 2 O 3. Abstract In this paper, the effect of post deposition annealing (PDA) on the chemical, structural, and electrical properties of the high-k Y 2 O 3 /Al 2 O 3 stacking dielectric on p-type 4H-SiC were studied. High-k dielectric provides a physically thicker film with equivalent capacitance, therefore better exploits the high breakdown strength of 4H-SiC in its MOSFET devices. The Y 2 O 3 /Al 2 O 3 stacking films were deposited using RF magnetron sputtering, with PDA in Ar ambient at 400 °C, 600 °C, 800 °C and 1000 °C. X-ray diffraction (XRD) and angle resolved X-ray photoelectron spectroscopy (XPS) results show that an Al 5 O 12 Y 3 crystal layer was formed in between Y 2 O 3 and Al 2 O 3 films after annealing above 600 °C. High resolution transmission electron microscope (HRTEM) was used to investigate the atomic structure and measure the thickness of each layer. Charges and dielectric strength of the stacking films were characterized by high frequency capacitance-voltage (C-V) and current-voltage (I-V) measurements. The lower charge density and higher dielectric strength were found after PDA at 800 °C and 1000 °C. [ABSTRACT FROM AUTHOR]

The evidences on the association of Helicobacter pylori (H. pylori) to coronary heart diseases (CHD) are conflicting. In order to answer this important but yet unanswered clinical health issue, a large cohort study such as big data from the Taiwan National Health Insurance Research Database should be more convincing. Therefore, we aimed to make use of these big data source to analyze and clarify the relevance of H. pylori eradication and CHD risks. We looked through a total of 208196 patients with peptic ulcer diseases (PUD) from the years of 2000 to 2011. First, 3713 patients who received H. pylori eradication within 365 days of the index date were defined as the group A. We randomly selected the same number of patients as cohort A from 55249 non-eradication patients to be the comparison group B using propensity scores (including age, gender and comorbidity) so that we could control the confounding variables of CHD and mortality. Importantly, we perform sensitivity analysis for the time-dependent association between H. pylori eradication and risk of CHD, interactions between patient demographic characteristics and therapy by age (≥ or < 65 years old). The results showed that a trend of decreased association of CHD in patients with early eradication was observed compared to those without eradication (2.58% vs. 3.35%, p = 0.0905). The mortality rate was lower in early eradication subgroup compared to cohort B (2.86% vs. 4.43%, p = 0.0033). Interestingly, there was also significant difference observed in composite end-points for CHD and death in the early eradication subgroup (0.16% vs.0.57%, p = 0.0133). Further, the cumulative CHD rate was significantly lower in younger patients (< 65 years old) with H. pylori eradication therapy started < 1 year compared to those patients without eradication at all (p = 0.0384); the treatment did not appear to have an effect in older patients (≥ 65 years old) (p = 0.1963). Multivariate analysis showed that hypertension and renal diseases were risk factors for CHD in patients without eradication whilst younger age (< 65 years old) initiated with H. pylori therapy was a protective factor. In conclusion, the trend of decrease in CHD occurrence after early H. pylori eradication in addition to the significant decrease in composite end points for CHD and death, the significantly lower cumulative CHD rate in younger patients < 65 years old with H. pylori treated within 365 days suggested that there was positive association between H. pylori eradication and CHD. [ABSTRACT FROM AUTHOR]

Aims. Patients with chronic kidney disease (CKD) and Helicobacter pylori (H. pylori) infection have a higher incidence of gastroduodenal diseases and therefore are recommended to receive eradication therapies. This study aimed to assess the efficacy of a 7-day standard triple therapy in patients with CKD (eGFR < 60 ml/min/1.73 m2) and to investigate the clinical factors influencing the success of eradication. Methods. A total of 758 patients with H. pylori infection receiving a 7-day standard first-line triple therapy between January 1, 2013, and December 31, 2014, were recruited. Patients were divided into two groups: CKD group (N=130) and non-CKD group (N=628). Results. The eradication rates attained by the CKD and non-CKD groups were 85.4% and 85.7%, respectively, in the per-protocol analysis (p=0.933). The eradication rate in CKD stage 3 was 84.5% (82/97), in stage 4 was 88.2% (15/17), and in those who received hemodialysis was 87.5% (14/16). There were no significant differences in the various stages of CKD (p=0.982). The adverse events were similar between the two groups (3.1% versus 4.6%, p=0.433). Compliance between the two groups was good (100.0% versus 99.8%, p=0.649). There was no significant clinical factor influencing the H. pylori eradication rate in the non-CKD and CKD groups. Conclusions. This study suggests that the H. pylori eradication rate and adverse rate in patients with CKD are comparable to those of non-CKD patients. [ABSTRACT FROM AUTHOR]

In this study, the displacement damage dose (DDD) effects of proton irradiation on bulk crystal and interfacial properties of 4H-SiC MOS capacitors (MOSCs) were investigated. The Monte Carlo calculation code named SRIM (Stopping and Range of Ions in Matter) was first used to predict the depth profiles and damage distributions of protons. The 4H-SiC MOSCs were irradiated with 60, 100, 150 keV protons to fluences ranging from 5 × 1011 to 5 × 1013 cm−2. Capacitance-voltage (C-V) curves of the MOSCs were then measured to characterize the variation of the electrically active defects in 4H-SiC MOSCs. The results revealed that the non-ionization energy loss of incident protons leads to the accumulation of the primary defects in bulk SiC crystal as well as the increase of the interface traps between SiO 2 and SiC crystal. A distinctive bump phenomenon was found in the weak inversion region of the C-V curve and it became more prominent with the increase of proton fluence, providing evidence for the existence of bulk traps. Furthermore, the incident proton energy is also a crucial factor in interface deterioration, suggesting that more interface traps would be formed when the proton damage peak is closer to the SiO 2 /SiC interface. • Displacement damage effects of proton irradiation on 4H-SiC MOSCs were investigated. • Non-ionization energy loss of protons leads to the buildup of bulk and interface traps. • A distinctive bump in weak inversion region of C V curve implies the existence of bulk traps. • Lowering proton incident energy accelerates the interface deterioration of SiC MOSCs. [ABSTRACT FROM AUTHOR]

In this letter, the potential of single crystalline 4H-polytype silicon carbide (4H-SiC) based microelectromechanical structures as resistance thermometer for high temperature sensing were explored. A dopant-selective photoelectrochemical etching process was applied to release the sensing element – suspended microstructures on 4H-SiC substrate. Residual stress and stress gradient in the microstructure before and after release was examined by micro-Raman spectroscopy. Electrical resistance of the suspended microstructures at different temperatures were characterized and analyzed by a temperature-dependent electron mobility model. [ABSTRACT FROM AUTHOR]

A novel transient voltage suppressor (TVS) that features ultralow capacitance is proposed. This structure is able to reduce the input capacitance by 21.1%, and is designed to protect against electrostatic discharge (ESD) issues for high-speed ports. The device is also able to withstand IEC 61000-4-2 contact testing at ±14 kV and transmission line pulse (TLP) testing at 20 A. The device is fabricated using a typical planar Bipolar-CMOS-DMOS (BCD) process. By slotting the doping well to decrease the concentration of diodes, a TVS with an ultralow Cj is obtained without the need to add to the process procedures or without damaging the ESD capability. [ABSTRACT FROM PUBLISHER]

A mathematical model is developed by fitting the discharging curve of LiFePO 4 batteries and used to investigate the relationship between the state of charge and the closed-circuit voltage. The proposed mathematical model consists of dual exponential terms and a constant term which can fit the characteristics of dual equivalent RC circuits closely, representing a LiFePO 4 battery. One exponential term presents the stable discharging behavior and the other one presents the unstable discharging behavior and the constant term presents the cut-off voltage. [ABSTRACT FROM AUTHOR]

• Not only surface nano-pit impacts leakage current but also dislocation itself. • Threading edge dislocation dominates leakage current in 4H-SiC Schottky diodes. • Surface potential of threading edge dislocation is higher than screw dislocation. • Threading dislocation changes the band-structure of Schottky barrier by stain-field. This study compared the influences of threading edge and screw dislocation (TED and TSD) defects and their work functions on electrical property of leakage current statistically through the reverse current–voltage characteristics of dozens of pieces of 4H-SiC Schottky barrier diodes (SBDs). The experimental results indicated that TEDs correlated strongly more than TSDs to the leakage current in 4H-SiC SBDs under the soft-breakdown regime. Furthermore, Kelvin probe force microscopy revealed that the work function at TED site was about 15 meV lower than that at TSD site. We proposed a possible mechanism based on band-structure near the Schottky barrier, which illustrated that TED site possesses the larger degree of band bending and therefore increases the tunneling transmission probability in contrast to TSD site. [ABSTRACT FROM AUTHOR]

This paper reports extensive modelling and analysis of the temperature dependence on the device characteristics of the AlGaN/GaN high electron mobility transistors (HEMTs). A physics-based model is proposed in this study in order to correctly predict the gate flat-band Schottky barrier height, energy band Fermi-level (EC–EF) at the AlGaN/GaN interface, two-dimensional electron gas sheet density, gate threshold and (ID–VG) at sub-threshold voltages, and drain current–voltage (ID–VD) characteristics under various high-temperature conditions. The analytical results are then verified by comparing with the laboratory measurement as well as the numerical results obtained from the Sentaurus TCAD simulation. The proposed model is found to be useful for power electronic device designers on the prediction of the AlGaN/GaN HEMT device performance under high-temperature operation. [ABSTRACT FROM AUTHOR]

In this paper, important parameters of the p-buried layer of a high-voltage reduced surface field p-n diode are analyzed and discussed in terms of effects on device performance, including breakdown voltage and specific turn-on resistance, Ron,sp. Guidelines for optimizing the vertical position, lateral location, and doping concentration of the p-buried layer are suggested. The experimental results demonstrate that the p-n diode with the proposed p-buried layer optimization design can improve breakdown voltage by 30.7% but only increases 2.7% in specific on-resistance Ron,sp. [ABSTRACT FROM PUBLISHER]

Highlights: [•] Wet oxidation at 950°C followed by NO anneal at 1175°C reduces the interface trap density to 4–6×1011 cm−2 eV−1. [•] The positive flat band voltage shift caused by low temperature wet oxidation can be suppressed by the following NO anneal. [•] The oxide breakdown fields for Al- and N-implanted C-face 4H-SiC samples are about 1.5 and 5MVcm−1, respectively. [•] The oxide breakdown field of dry oxidation at 950°C is the same as that of wet oxidation at 950°C. [ABSTRACT FROM AUTHOR]

This paper presents a 700-V high-voltage laterally diffused metal-oxide–semiconductor (LDMOS) field-effect transistor with a p-body_Extension reduce surface field (RESURF) structure. Experimental results demonstrate that the low ON resistance and breakdown voltage (BV)-R\rm{ON,sp} figure of merit approach the ideal Baliga's power law, in addition, breaks the quasi-saturation limitation with enhanced device safe operating area (SOA). The optimal charge balance and geometrical design to achieve the lowest specific ON resistance (R\rm{ON,sp}) with the desired maximum high BV are displayed and discussed by simulations and experimental results. The 2-D simulations confirmed that, compared with conventional triple-RESURF structures, the presented device provides a fourfold reduction in the surface electric field on the source side and a 32% improvement in blocking voltage. The specific ON resistance demonstrates superior 40% lower performance than published Junction Isolation LDMOS device families. In addition, its twofold increase in SOA extension can improve the performance of circuit designs for switching power supply applications. [ABSTRACT FROM AUTHOR]

Abstract: Thermal and pulsed excimer laser treatments have been applied for the post-implant anneals of Al- and N-implanted 3C-SiC samples to recover crystal damage caused by the ion implantation. FTIR reflectivity spectra show that the thermal anneal carried out at 1350°C for 30min has the better damage recovery in a range of the reststrahlen bands of both Al- and N-implanted samples. However, shoulders in the XRD spectra caused by the implantation indicate that a thermal anneal cannot completely recover the damage throughout an entire sample. For the Al-implanted samples, laser pulses with various energy densities can move shoulders to higher 2θ angles and then merge shoulders with the major peaks at the total energy density of 583.7J/cm2. 150 shots of laser pulses at the energy density of 256mJ/cm2 and combining with other energy densities can be used to recover damage in a range of the reststrahlen band which is induced by laser irradiation. Furthermore, the damage caused by the implantation in N-implanted samples is not close to the major peak in the XRD spectra, which can be improved by the laser pulses as well, but not moved to higher 2θ angles. However, the applied energy densities create extra damage in a range of the reststrahlen band. [Copyright &y& Elsevier]

In this paper, it is the first time that the effect of self-heating of LDMOS transistors operating in the so-called expansion regime of the output characteristics is studied. Experimental characterization and numerical simulations are used to demonstrate that, in order to explain the origin of the current enhancement phenomenon observed in the output characteristics of LDMOS transistors biased at high gate and drain voltages (which is named as the expansion regime), the thermal effect of the device self-heating, in addition to the proposed intrinsic MOSFET saturation, has to be considered. This is supported by analyzing the temperature, charged carrier velocity, impact ionization rate, and electric field at different positions in the LDMOS transistors biased at different gate and drain voltages. [ABSTRACT FROM PUBLISHER]

In this paper, the relation between the surface electric field and the temperature distribution dependence on the drift-region doping concentration in a 30-V asymmetric drain-extended MOSFET is studied. For the case of high drift-region concentration, the drain resistance is low, and the current density is high, which induces a high nonuniform temperature distribution in the transistor, which in turn reduces the carrier mobility and causes a negative drain resistance. For the case of low drift-region concentration, a uniform temperature distribution is obtained. However, the different drift-region concentration changes the location of the maximum temperature from the gate-overlapped drift region for the high concentration case to the drain-side contact region for the low concentration case under the high VGS and VDS conditions. Therefore, the self-heating effect is also changed by the redistribution of the electric field in the drift region. [ABSTRACT FROM AUTHOR]

A 60 GHz monolithic low-noise amplifier (LNA) fabricated with 0.15-μm gallium-arsenic pseudomorphic high-electron mobility transistors is presented.Using a three-stage cascaded topology and in-stage transmission lines, the LNA is designed using 5 V power supply voltage. Measured results of the LNA show the peak gain of 13.5 dB and the lowest noise figure of 5.15 dB around 61 GHz, and the 1 dB compression point (P1dB) of the LNA is −10 dBm. The LNA also demonstrates a complete design flow for millimeter-wave applications. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 54:329-332, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26525 [ABSTRACT FROM AUTHOR]

This paper presents, for the first time, the study of the application of a lateral diffused metal–oxide–semiconductor field-effect transistor (LDMOSFET) in a common-gate configuration to radio-frequency (RF) transmit/receive (T/R) switching circuits. A single-pole double-throw (SPDT) 900-MHz T/R switch is implemented using 0.25-\mu\m LDMOSFET foundry technology. Measured results show that our switching circuit can achieve a low insertion loss of 0.82 dB and a high power handling capability of 27 dBm. This result is promising in integrating power management integrated circuits, RF power amplifiers, and switching circuits in a single chip, based on LDMOSFET technology, to realize an RF transmit front-end system-on-chip solution. [ABSTRACT FROM AUTHOR]

Abstract: A method for the synthesis of millimeter-scaled graphene films on silicon carbide substrates at low temperatures (750°C) is presented herein. Ni thin films were coated on a silicon carbide substrate and used to extract the substrate’s carbon atoms under rapid heating. During the cooling stage, the carbon atoms precipitated on the free surface of the Ni and formed single-layer or few-layer graphene. The result shows that the number of graphene layers might be further controlled by appropriate process conditions. In contrast to the epitaxial graphene synthesis on single crystal silicon carbide, the graphene prepared here are continuous over the entire Ni-coated area, and can be stripped from the substrate much more easily for further characterization. The large-scaled, low temperature and transferable features of our method suggest the potential for future graphene-based applications. [Copyright &y& Elsevier]

A simple scheme is proposed to increase the hold voltage and not change the original trigger voltage of a silicon‐controlled rectifier (SCR) to enhance its latch‐up immunity without changing the device dimensions. It is found that using the lightly doped P‐diffusion instead of the highly doped P+ diffusion as the P emitter of the anode can increase the hold voltage of an SCR. [ABSTRACT FROM AUTHOR]

The institutional review board number is incorrect, it should be No. 104-3133B. [ABSTRACT FROM AUTHOR]

In this paper, performances of a 4H-SiC UMOSFET with split gate and P+ shielding in different configurations are simulated and compared, with an emphasis on the switching characteristics and short circuit capability. A novel structure with the split gate in touch with the P+ shielding is proposed. The key design issues for 4H-SiC UMOSFETs are trench gate dielectric protection and reverse transfer capacitance Crss reduction. Based on simulation results, it is concluded that a UMOSFET with a gate structure combining split gate grounded to the trench bottom protection P+ shielding layer and a current spreading layer is achieved to yield the best compromise between conduction, switching, and short circuit performance. The split-gate design can effectively reduce Crss by shielding the coupling between the gate electrode and the drain region. The P+ shielding design not only protects the oxide at trench bottom corners but also minimizes the short channel effect due to drain-induced barrier lowing and the channel length modulation. Trade-off of the doping concentration of current spreading layer for UMOSFET is also discussed. A heavily doped current spreading layer may increase Crss and influence the switching time, even though RON,SP is reduced. [ABSTRACT FROM AUTHOR]