Search results for "Semiconductor"

Molecular dynamics simulations of heavy ion induced defects in SiC Schottky diodes

2018

Heavy ion irradiation increases the leakage current in reverse-biased SiC Schottky diodes. This letter demonstrates, via molecular dynamics simulations, that a combination of bias and ion-deposited energy is required to produce the degradation. Peer reviewed

Molecular dynamics simulations of heavy ion induced defects in SiC Schottky diodes

2018

Heavy ion irradiation increases the leakage current in reverse-biased SiC Schottky diodes. This work demonstrates, via molecular dynamics simulations, that a combination of bias and ion-deposited energy is required to produce the degradation peerReviewed

A cross‐sectional, multi‐center study on treatment of facial acne scars with low‐energy double‐pass 1450‐nm diode laser

2020

Acne scars are the ultimate outcome of acne vulgaris, a prevalent skin disorder affecting the pilo-sebaceous unit. Laser resurfacing has been demonstrated to be an efficient therapy option for acne scars. Hence, we adopted this concept and conducted a study to evaluate the safety and efficacy of low-energy double-pass 1450-nm diode laser on acne scars. This study was conducted on 48 patients with acne scars, treated at 4-week interval with low-energy double-pass 1450-nm diode laser. Patients were evaluated clinically and with photographs, at day 0, first month and third month post the final treatment and during follow-up visit. Five treatment sessions were completed by all patients. Approxi…

A Monte Carlo-aided design of a modular 241Am-Be neutron irradiator

2013

Monte Carlo studies aimed at designing a modular 241Am-Be neutron irradiator for testing neutron detectors and personal dosimeters and processing large volume samples are reported in this study. The evaluation of the shapes and thicknesses of the moderator and shielding materials was carried out by a MCNP5 Monte Carlo simulation code. The reliability of the simulation was experimentally verified by the activation of gold foils and TLD dosimeter measurements in an irradiation cell placed at the center of the test configuration.

Peltier effect-based temperature challenge: an improved method for diagnosing cold urticaria.

2004

Efficiency of concentration photovoltaic cells governed by luminescence processes

2013

The development of multi-junctions III-V semiconductors solar cells, that combine high conversion efficiency (over 40%) and capability of working under high illumination intensity (up to 1000 suns), has stimulated a rapid growth of concentrating photovoltaic (CPV) technology. The performance of these cells is based on the matching between the semiconductors band gap and the solar spectrum so as to optimize the current balancing between the subcells. This requirement is also important in connection with the CPV modules using lenses, mirrors, optical coupling compounds that introduce a wavelength dependent response to the sunlight. Therefore, care must be exercised in designing optimum cells …

Review: Electrostatically actuated nanobeam-based nanoelectromechanical switches – materials solutions and operational conditions

2018

This review summarizes relevant research in the field of electrostatically actuated nanobeam-based nanoelectromechanical (NEM) switches. The main switch architectures and structural elements are briefly described and compared. Investigation methods that allow for exploring coupled electromechanical interactions as well as studies of mechanically or electrically induced effects are covered. An examination of the complex nanocontact behaviour during various stages of the switching cycle is provided. The choice of the switching element and the electrode is addressed from the materials perspective, detailing the benefits and drawbacks for each. An overview of experimentally demonstrated NEM swi…

Síntesis y caracterización de compuestos de Cu(II) con derivados triazólicos. Estudio de su actividad como potenciales nucleasas químicas

2014

The main goal of this PhD thesis concerns the development of artificial metallonucleases based on copper(II)-1,2,4-triazole compounds. In order to do so, we have obtained metal compounds of different nuclearities by reaction of a new family of 1,2,4-triazole ligands with copper(II) salts. The ligands own the characteristic triazole properties upon coordinating to metals and also integrate DNA binding units (aromatic moieties) with the aim of increasing the affinity of the corresponding metal complexes to double strand DNA. We have also chosen the copper(II) ion due to its intrinsic redox and coordination properties. Here we present our conclusions in relation with their structure/activity a…

Characterisation of single semiconductor nanowires by non-destructive spectroscopies

2015

Los nanohilos semiconductores (NWs, de su nombre inglés, nanowires) tienen una amplia gama de aplicaciones en el campo de la optoelectrónica (emisores de luz y diodos láser), nano-electrónica (circuitos lógicos y transistores de efecto de campo), y detección y producción de energía (células solares). En términos generales, los NWs pueden ser descritos como nanoestructuras de forma alargada con diámetros que van típicamente de decenas a cientos de nanómetros, y con longitudes que oscilan desde pocas hasta las decenas de micras. Dicha morfología ofrece dos ventajas principales en comparación con las capas: su alta relación superficie-volumen y su mayor calidad cristalina, ambas beneficiosas p…

Optical Properties of III-V Nanowires and Their Application for Charge Transport and Single-Photon Emission

2012

This work covers the optical characterization of III-V semiconductor nanowires and their application for charge transport and for single-photon emission. InAs nanowires have been investigated by Raman scattering and PL spectroscopy. The possibility to grow nanowires with a crystal structure different from its bulk counterpart has aroused a lot of interest in their optical and electronic properties. Here, the optical phonon modes of wurtzite InAs nanowires have been studied by polarized Raman scattering. For the first time, Raman measurements on a single InAs nanowire have revealed the A1(TO) and E2h optical phonon modes of the wurtzite structure. Additional resonant Raman scattering experim…