Semiconductor Structures
Mostrando 1-12 de 58 artigos, teses e dissertações.
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1. Influencia de los tratamientos térmicos en recubrimientos anódicos nanotubulares de TiO2
ABSTRACT TiO2 is a semiconductor widely used in heterogeneous photocatalysis processes for water decontamination. Several studies indicate that ordered nanostructures in anatase phase improve the photocatalytic properties with respect to other morphologies and crystal structures of TiO2. The aim of the present work is to evaluate the influence of different t
Matéria (Rio J.). Publicado em: 19/07/2018
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2. HIGH PRESSURE BEHAVIOR OF CRYSTALLINE DIHYDROXYLAMMONIUM 5,5'-BISTETRAZOLE-1,1'-DIOLATE: FIRST-PRINCIPLES STUDY
Density functional theory (DFT) periodic calculations were performed to study the geometrical and electronic structures of energetic compound dihydroxylammonium 5,5'-bistetrazole-1,1'-diolate (TKX-50) under the pressure ranging from 0 to 400 GPa. The optimized crystal structure by the local density approximation (LDA) with CA-PZ functional matches well with
Quím. Nova. Publicado em: 2017-10
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3. Analysis of electronic structure of boron nitride nanotubes with different positions of intrinsic impurities
The pristine boron nitride nanotubes have a large direct band gap around 5 eV. This band gap can be engineered by doping. We investigate electronic structure of the doped hexagonal boron nitride (5,5) nanotubes using the linearized augmented cylindrical wave method. In particular, this work focuses on systematical study of the band gap and the density of sta
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2014-12
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4. Aplicações de corrosão por plasma usando reatores ICP e RIE para tecnologia MEMS / Plasma etching applications using ICP and RIE reactors for MEMS technology
This thesis is based on etching processes applications in cold plasmas (room temperature) using RIE (Reactive Ion Etching) and ICP (Inductively Coupled Plasma), as reactors, applied to specific areas of microelectronics and MEMS devices in semiconductors industries and laboratories. Five applications are presented: Thinning gate CMOS Transistor - conventiona
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 28/08/2012
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5. Elaboração de indicadores bibliométricos a partir de patentes de nanotecnologia
The need to assign values to consumer and globalization have created a new format in the economy. These phenomena have increased investments in technology until the crisis of 1970 that generated a reduction in economic growth and consequently reduction in research funding. This context created resources that could gauge the areas that lacked development. One
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 27/02/2012
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6. Estudo da interação de nanotubos de carbono com substrato de quartzo cristalino
Single wall carbon nanotubes (SWNTs) are quasi-onedimensional structures consisting of a rolled up graphene nanoribbon. Due to their unusually large surface-to-volume ratio, SWNTs are strongly affected by the environment. Contact with a supporting substrate modifies their properties, and such interactions have been broadly studied as either a drawback or a s
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 24/03/2011
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7. Estudo de pontos quânticos auto-organizados de InAs por fotoluminescência
Semiconductor structures with high confinement degree, such as quantum wells, quantum wires and quantum dots, have been of great interest, both from the technological point of view and for basic research. Self-Assembled Quantum Dots (SAQD`s) appear spontaneously, as a consequence of the lattice mismatch of the material deposited in relation to the substrate,
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 26/02/2010
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8. The role of nonequilibrium thermo-mechanical statistics in modern technologies and industrial processes: an overview
The nowadays notable development of all the modern technology, fundamental for the progress and well being of world society, imposes a great deal of stress in the realm of basic Physics, more precisely on Thermo-Statistics. We do face situations in electronics and optoelectronics involving physical-chemical systems far-removed-from equilibrium, where ultrafa
Brazilian Journal of Physics. Publicado em: 2010-03
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9. Propagação não linear de pulsos em estruturas 1D com band gap fotonico / Nonlinear pulse propagation in one-dimensional photonic band gap structures
The interaction of ultrashort optical pulses with photonic band gap materials has been studied by considering light propagation through one-dimensional photonic band gap structures, composed of a periodic multilayer stack of dielectric materials whose unitary cell consists of a pair of layers with different refractive indices n1and n2, respectively. One of t
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 17/08/2009
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10. Phosphorus emitter and metal - grid optimization for homogeneous (n+p) and double-diffused (n++n+p) emitter silicon solar cells
This work focuses on studying two types of structure: homogeneous and double-diffused emitter silicon solar cells. The emitter collection efficiencies and the recombination current densities were studied for a wide range of surface dopant concentrations and thicknesses. The frontal metal-grid was optimized for each emitter, considering the dependence on the
Materials Research. Publicado em: 2009-03
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11. Potential performance of SiC and GaN based metal semiconductor field effect transistors
A Monte Carlo simulation has been used to model steady-state electron transport in SiC and GaN field effect transistor. The simulated device geometries and doping are matched to the nominal parameters described for the experimental structures as closely as possible. Simulations of SiC MESFETs of lengths 2, 2.6 and 3.2 µm have been carried out and compared t
Brazilian Journal of Physics. Publicado em: 2009-03
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12. ESTUDO DE PRIMEIROS PRINCíPIOS DE DEFEITOS NATIVOS EM MONÓXIDO DE BERÍLIO / FIRST PRINCIPLES STUDY OF NATIVE DEFECTS IN BERYLLIUM MONOXIDE
The present thesis shows a study of native defects (vacancies and antisites) in Beryllium Monoxide (BeO) by means of first principle calculations within Density Functional Theory (DFT). We made use of Local Density Aproximation (LDA) in order to approach correlation and shift term, and ultrasoft pseudopotentials in order to describe the electron-core interac
Publicado em: 2009