Thermal annealing behaviour on electrical properties of Pd/Ru Schottky contacts on n-type GaN

We have investigated the electrical properties of Pd/Ru Schottky contacts on n-GaN as a function of annealing temperature by current-voltage (I-V) and capacitance-voltage (C-V) measurements. The Schottky barrier height of the as-deposited Pd/Ru contact is found to be 0.67 eV (I-V) and 0.79 eV (C-V), respectively. Measurements showed that the Schottky barrier height increased from 0.68 eV (I-V) and 0.80 eV (C-V) to 0.80 eV (I-V) and 0.96 eV (C-V) as the annealing temperature is varied from 200 °C to 300 °C. Upon annealing at 400 °C and 500 °C, the Schottky barrier height decreased to 0.73 eV (I-V) and 0.85 eV (C-V) and 0.72 eV (I-V) and 0.84 eV (C-V), respectively. It is noted that the barrier height further decreased to 0.59 eV (I-V) and 0.72 eV (C-V) when the contact is annealed at 600 °C. The change of Schottky barrier heights and ideality factors with annealing temperature may be due to the formation of interfacial compounds at the Ru/Pd/n-GaN interface. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2788

Satellite Remote Sensing and Field Studies on Narrowing of Three Sea Mouths of Pulicat Lake Sanctuary and Ecological Impact

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

Evaluation of the accuracy, precision and validity of hydrophylic vinyl polysiloxane impression material for bite mark analysis

The present study was undertaken to assess the accuracy, precision and validity of hydrophilic Vinyl Poly Siloxane [VPS] impression material for bite mark documentation and analysis. Medium body VPS impressions of maxillary and mandibular anterior teeth among thirty subjects were taken and dental stone casts prepared. Hollow volume overlays were made and metric analysis was done using advanced imaging software like Adobe Photoshop - 9 and Image J. These values were compared to the measurements taken from bite mark impressions of the same 30 individuals on wax wafers using light body VPS material. The mean differences in the parameters measured by the different techniques were compared using Intra Class Correlation Coefficients [ICCC]. Additionally validity parameters such as sensitivity, specificity, positive and negative predictive value were computed

Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.

BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700

Nations within a nation: variations in epidemiological transition across the states of India, 1990–2016 in the Global Burden of Disease Study

18% of the world's population lives in India, and many states of India have populations similar to those of large countries. Action to effectively improve population health in India requires availability of reliable and comprehensive state-level estimates of disease burden and risk factors over time. Such comprehensive estimates have not been available so far for all major diseases and risk factors. Thus, we aimed to estimate the disease burden and risk factors in every state of India as part of the Global Burden of Disease (GBD) Study 2016

Influence of Ta2O5 Interfacial Oxide Layer Thickness on Electronic Parameters of Al/Ta2O5/p-Si/Al Heterostructure

We describe the impact of Ta2O5 interfacial oxide layer thickness (ranging from 100-350 nm) on electrical and structural properties of Al/Ta2O5/p-Si/Al Metal-Insulator-Semiconductor (MIS) Schottky barrier diodes using RF magnetron sputtering. We studied the Schottky barrier device parameters such as ideality factor, barrier height and series resistance and are evaluated from current-voltage (I-V) measurements. The barrier height and ideality factor values are significantly varying with Ta2O5 oxide layer thickness and found to be 0.58 eV, 2.35, 0.71 eV, 2.10 and 0.78 eV, 1.87 for 20, 40 and 60 nm, respectively. It was noticed that the calculated barrier height and ideality values for this prepared Al/Ta2O5/p-Si/Al MIS Schottky barrier diode were greatly improved than those conventional metal-semiconductor (MS) Schottky diodes. The XRD studies revealed that the 100-nm thickness film exhibited poor crystallinity whereas 200 and 350 nm thickness films showed improved crystallinity with orthorhombic phase of -Ta2O5. The presence of this orthorhombic phase of -Ta2O5 is confirmed with FTIR studies. To explore the structural transformations in Ta2O5 films with varying thicknesses, Raman spectroscopy was utilized. In addition, the improvement in Schottky diode parameters was correlated with the enhanced crystallinity noticed in XRD studies

Zr-doped SnO2 thin films synthesized by spray pyrolysis technique for barrier layers in solar cells

In the present work, we investigated the effect of Zr doping (0-6 at%) on the structural, electrical, and optical properties of tin oxide (SnO2) thin films deposited onto glass substrates using a spray pyrolysis technique. The room-temperature X-ray diffraction pattern shows that all deposited films exhibit polycrystalline tetragonal structure. The pure SnO2 film is grown along a preferred (200) direction, whereas Zr-doped SnO2 (Zr:SnO2) films started growing along the (220) orientation along with a high intensity peak of (200). Scanning electron microscope (SEM) and atomic force microscope (AFM) images showed that the grains of the films are spherical in structure, and the grain size decreased with increasing of Zr concentration. The optical transmission spectra of deposited films as a function of wavelength confirm that the average optical transmittance is > 85% for Zr:SnO2 films. The value of the optical bandgap is significantly decreased from 3.94 to 3.68 eV with increasing Zr concentration. Furthermore, the electrical measurements found that the sheet resistance (R-sh) and resistivity (rho) values are decreased with increasing of Zr doping. The lowest values of R-sh = 6.82 Omega and rho = 0.4 x 10(-3) Omega cm are found in 6-at% Zr-doped SnO2 film. In addition, a good efficiency value of the figure of merit (phi = 3.35 x 10(-3) Omega(-1)) is observed in 6-at% Zr-doped SnO2 film. These outstanding properties of Zr-doped SnO2 films make them useful for several optoelectronic device applications

Influence of sputter power on structural and electrical properties of TiO2 films for Al/TiO2/Si gate capacitors

Titanium dioxide (TiO2) thin films were deposited onto p-Si substrates held at room temperature by reactive Direct Current (DC) magnetron sputtering at various sputter powers in the range 80-200W. The as-deposited TiO2 films were annealed at a temperature of 1023K. The post-annealed films were characterized for crystallographic structure, chemical binding configuration, surface morphology and optical absorption. The electrical and dielectric properties of Al/TiO2/p-Si structure were determined from the capacitance-voltage and current-voltage characteristics. X-ray diffraction studies confirmed that the as-deposited films were amorphous in nature. After post-annealing at 1023K, the films formed at lower powers exhibited anatase phase, where as those deposited at sputter powers >160W showed the mixed anatase and rutile phases of TiO2. The surface morphology of the films varied significantly with the increase of sputter power. The electrical and dielectric properties on the air-annealed Al/TiO2/p-Si structures were studied. The effect of sputter power on the electrical and dielectric characteristics of the structure of Al/TiO2/p-Si (metal-insulator-semiconductor) was systematically investigated. Copyright (c) 2014 John Wiley & Sons, Ltd