Search results for "Icon"

Low cost, efficient hybrid solar cells

2017

Actualmente, existen diversas estrategias para producir energía limpia mediante fuentes renovables, pero es la explotación directa de la energía del Sol la que se presenta como una solución ideal, siendo la mayor fuente de energía verde en la Tierra. La potencia de la energía solar que llega a la Tierra cada año es del orden de 86000 TW (Terawatt, 1012 Watt). Esto representa 4800 veces la demanda energética anual del mundo, estimada en 18 TW. Además, todos los depósitos de energía fósil reconocidos (petróleo, carbón y gas) contienen todos juntos tan sólo una cantidad de energía equivalente a la recibida del Sol durante 56 días. Esta situación muestra claramente la necesidad de aprovechar es…

Demo 49. Termómetro de resistencia

2013

Objetivo: Entender el funcionamiento de los termómetros de resistencia. Observar cómo la resistencia eléctrica varía con la temperatura de dos formas diferentes.

Ionic-electronic interaction in optoelectronic and sensing devices

2016

En este trabajo se estudian las interacciones entre cargas electrónicas e iónicas y sus aplicaciones en sensores y dispositivos optoelectrónicos. El mecanismo de funcionamiento de los dispositivos optoelectrónicos actualmente más comunes, como los transistores de efecto de campo de capa fina (TFTs), los diodos emisores de luz (LEDs) y las células solares se basa solamente en procesos electrónicos, lo que significa que los efectos de cargas iónicas están ausentes, son irrelevantes o incluso perjudiciales para el propósito de dichos dispositivos. Sin embargo, muchas aplicaciones se benefician de la presencia de iones en la estructura de un dispositivo. Un ejemplo típico en el campo de investi…

Semiotica e Iconologia

2004

In Semiotica e Iconologia si è condotta una riflessione, partendo da alcune letture significative di opere d’arte di età preistorica, moderna e contemporanea, avvalendosi delle metodologie della semiotica e dell’iconologia. La lettura di un’opera è sempre un’operazione complessa che richiede, tavolta, il ricorso alla semiotica, o meglio alla semantica delle arti, come nel caso di Pollock, il quale espone la materia senza la presenza di elementi iconografici. Altre volte, si deve ricorrere all’uso dell’iconologia, come si può, esemplarmente vedere nel saggio pionieristico di M. Calvesi, intitolato Iconologia dell’Astrattismo. Vi sono casi e momenti della storia dell’arte, come nel caso del C…

Ancora sulla sentenza 30 marzo 2000 n°1835 del Consiglio di Stato

2002

Bio-politics of the Screen. Gaze, Power and Digital Exhibition

2010

Effects of Excimer Laser Irradiation on the Morphological, Structural, and Electrical Properties of Aluminum-Implanted Silicon Carbide (4H-SiC)

2022

This paper reports on the effects of excimer laser irradiation on an aluminum (Al)-doped silicon carbide (4H-SiC) layer. Specifically, high-concentration (1 × 1020at/cm3) Al-implanted 4H-SiC samples were exposed to a few pulses of 308 nm laser radiation (pulse duration of 160 ns), with fluence varying from 1.0 to 2.8 J/cm2. As a starting point, the laser-induced modifications of the morphological, microstructural, and nanoelectrical properties of the exposed 4H-SiC surface were monitored by combining different techniques. From these investigations, an evolution of the surface morphology was observed that can be ascribed to a conversion during irradiation of the uppermost part of the 4H-SiC …

Charge Transport Mechanisms in Heavy-Ion Driven Leakage Current in Silicon Carbide Schottky Power Diodes

2016

Under heavy-ion exposure at sufficiently high reverse bias voltages silicon carbide (SiC) Schottky diodes are observed to exhibit gradual increases in leakage current with increasing ion fluence. Heavy-ion exposure alters the overall reverse current-voltage characteristics of these diodes, leaving the forward characteristics practically unchanged. This paper discusses the charge transport mechanisms in the heavy-ion damaged SiC Schottky diodes. A macro model, describing the reverse current-voltage characteristics in the degraded SiC Schottky diodes is proposed. peerReviewed

Effect of the Si doping on the properties of AZO/SiC/Si heterojunctions grown by low temperature pulsed laser deposition

2020

Abstract The structural and photoelectrical properties of Al-doped ZnO (AZO)/SiC/p-Si and AZO/SiC/n-Si heterojunctions, fabricated at low temperature by pulsed laser deposition, were investigated by means of a number of techniques. Raman analysis indicates that SiC layers have the cubic 3C-SiC phase, whilst X-ray diffraction measurements show that AZO films exhibit a hexagonal wurtzite structure, highly textured along the c-axis, with average crystallites size of 35.1 nm and lattice parameter c of 0.518 nm. The homogeneous and dense surface morphology observed by scanning electron microscopy was confirmed by atomic force microscopy images. Moreover, UV–Vis-NIR spectra indicated a high trans…

Single Event Burnout of SiC Junction Barrier Schottky Diode High-Voltage Power Devices

2018

Ion-induced degradation and catastrophic failures in high-voltage SiC Junction Barrier Schottky (JBS) power diodes are investigated. Experimental results agree with earlier data showing discrete jumps in leakage current for individual ions, and show that the boundary between leakage current degradation and a single-event-burnout-like effect is a strong function of LET and reverse bias. TCAD simulations show high localized electric fields under the Schottky junction, and high temperatures generated directly under the Schottky contact, consistent with the hypothesis that the ion energy causes eutectic-like intermixture at the metal- semiconductor interface or localized melting of the silicon …