Search results for "Semiconductor"

Quantum Mechanical Co-Adsorption Modelling of Real Electrically Controlled Semiconductor Gas Sensors

2009

Abstract Co-adsorption of several gases is still a challenge due to the variety of reaction paths at the sensitive surface, and their competition for the adsorption sites. With an extended Wolkenstein model and the gas kinetic theory, we find that for specific paths their sequence of exposition has an important influence on the layer resistance as well as on the time required to achieve equilibrium. Whilst only processes that involve charge transfer can be electrically detected, a good correlation between model and electrical measurements needs weakly chemisorbed (physisorbed) layers to be taken in account. Our study presents a SnO2 nano-film sensor with electrical control electrodes expose…

Review Article: Recommended reading list of early publications on atomic layer deposition - Outcome of the "virtual Project on the History of ALD"

2017

A Simulation Analysis for Assessing the Reliability of AC/DC Hybrid Microgrids - Part II: Port Area and Residential Area

2021

This paper reports the second part of a simulation study with the aim of evaluating the ability of two portions of a hybrid AC/DC MV/LV network in maintaining their operation in off-grid mode during the loss of the main AC grid due to a failure. In particular, this paper follows a dual purpose: first, it analysis two microgrids in a residential area and a port zone capability of operating in islanded mode, applying a probabilistic approach, while there is different energy use cases, and second is to evaluate some reliability indicators.

Oxidation-Induced Changes in the ALD-Al2O3/InAs(100) Interface and Control of the Changes for Device Processing

2018

InAs crystals are emerging materials for various devices like radio frequency transistors and infrared sensors. Control of oxidation-induced changes is essential for decreasing amounts of the harmful InAs surface (or interface) defects because it is hard to avoid the energetically favored oxidation of InAs surface parts in device processing. We have characterized atomic-layer-deposition (ALD) grown Al2O3/InAs interfaces, preoxidized differently, with synchrotron hard X-ray photoelectron spectroscopy (HAXPES), low-energy electron diffraction, scanning tunneling microscopy, and time-of-flight elastic recoil detection analysis. The chemical environment and core-level shifts are clarified for w…

Alkylthio-tetrasubstituted μ-Nitrido Diiron Phthalocyanines: Spectroelectrochemistry, Electrical Properties, and Heterojunctions for Ammonia Sensing.

2020

Alkylthio-tetrasubstituted μ-nitrido diiron phthalocyanine complexes are synthesized with n-butyl, iso-butyl, tert-butyl, and n-hexadecyl alkyl moieties. For the first time, a spectroelectrochemical investigation of μ-nitrido diiron phthalocyanines is achieved at all the redox steps. The complexes are stable in all their redox states, unlike their unsubstituted analogues. The interest of the present complexes is to prepare sensing devices by a solution processing method. Films are characterized by electronic absorption and Raman spectroscopies. Electrical measurements on resistors show the highly resistive behavior of these complexes, whatever the chain length. However, when combined with t…

Surfactant-assisted synthesis of Cd1−xCoxS nanocluster alloys and their structural, optical and magnetic properties

2010

We report the synthesis of Co-doped CdS nanoclusters (Cd1−xCoxS) for different doping concentrations (x = 0.10, 0.20 and 0.30) and characterization of their structural, optical, and magnetic properties. The structural properties studied by X-ray diffraction revealed hexagonal-greenockite structure and a decrease of the lattice parameters (a and c) with doping, showing incorporation of Co in the lattice. The morphology of the nanoclusters was studied by scanning electron microscopy. The optical absorption studies, using diffused reflectance spectroscopy, revealed that Co doping modifies the absorption band edge. Ferromagnetic phase was observed in the magnetization measurements at room-tempe…

Solvothermal Synthesis of Molybdenum–Tungsten Oxides and Their Application for Photoelectrochemical Water Splitting

2018

Molybdenum and tungsten oxides are of interest as semiconductors for the production of clean and sustainable energy. Here we show that synergistic effects arising from a combination of noncrystalli...

Large scale modelling of photo-excitation processes in materials with application in organic photovoltaics

2019

La energía fotovoltaica a partir de materiales orgánicos representa una opción muy atractiva, en términos de costo y flexibilidad, para generar electricidad. Sin embargo, las bajas eficiencias alcanzadas hasta ahora limitan la producción de dispositivos fotovoltaicos a escala comercial. En el intento de superar las bajas eficiencias hoy en día se dedican considerables esfuerzos en la investigación y el diseño de materiales orgánicos así como de arquitecturas de dispositivos más eficientes. En particular esta tesis doctoral presenta un trabajo de carácter fundamental sobre los procesos de fotoexcitación en dispositivos optoelectrónicos orgánicos, donde se usan química teórica y modelización …

Laser assisted decay spectroscopy at the CRIS beam line at ISOLDE

2012

A new collinear resonant ionization spectroscopy (Cris)beam line has recently been installed at Isolde, Cern utilising lasers to combine collinear laser spectroscopy and resonant ionization spectroscopy. The combined technique offers the ability to purify an ion beam that is heavily contaminated with radioactive isobars, including the ground state of an isotope from its isomer, allowing sensitive secondary experiments to be performed. A new programme aiming to use the Cris technique for the separation of nuclear isomeric states for decay spectroscopy will commence in 2011. A decay spectroscopy station, consisting of a rotating wheel implantation system for alpha decay spectroscopy, and thre…

Application of Ge Nanowire for Two-Input Bistable Nanoelectromechanical Switch

2013

Recently, several research groups presented bistable two-terminal nanoelectromechanical switches based on individual single-clamped active element. All presented devices had one input electrode. Similar devices having two or more input electrodes have not been yet investigated. In this work we present the two-input bistable controlled nanoelectromechanical switch based on an individual single-clamped Ge nanowire. The switch is realised using in-situ SEM technique and operating due to balancing of electrostatic, adhesion and elastic forces. The operation conditions of the device are investigated and presented. The advantages and drawbacks of the device are discussed. DOI: http://dx.doi.org/1…