Diffusion In Semiconductors
Mostrando 1-11 de 11 artigos, teses e dissertações.
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1. Efeito de interface nas propriedades ópticas de pontos quânticos de InP/GaAs / Interface effect on the optical properties of InP/GaAs quantum dots
We studied the effect of different interface conditions on the optical properties of InP/GaAs self-assembled quantum dots grown by chemical beam epitaxy in the Stranskii-Krastanov mode. InP/GaAs quantum dots is expected to present type II band alignment, and only electrons are confined, whereas the holes are localized in the GaAs layers around the quantum do
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 27/08/2012
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2. Simulação da dinâmica do estado excitado em semicondutores orgânicos / Simulation of the excited state dynamics in organic semiconductors
In the present work, the Monte Carlo method and the direct numerical integration of the Master Equation were employed to simulate the excitation spectral diffusion process in light emitting polymeric systems. The methodology employed a competition among the internal intra-molecular relaxation, the inter-molecular incoherent energy transfer via Förster mecha
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 25/04/2012
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3. Estudo de materiais, estruturas de dispositivos e fenômenos de transporte em sistemas fotovoltaicos híbridos orgânico-inorgânico / Study of materials, device structures and transport phenomena in hybrid photovoltaic systems
Recently a fast development in organic and hybrid photovoltaic field has been observed. Such devices are fabricated by organic semiconductors within components of a heterojunction, in which bulk heterojunctions obtained via interpenetrating networks at the sub-20-nm length scale. It permits the effective collection of photogenerated charge carriers even with
Publicado em: 2010
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4. Processos litográficos em filmes epitaxiais de compostos IV-VI para medidas Hall e o estudo da dopagem do telureto de chumbo com flureto de bário / Lithographic processes in epitaxial films of IV-VI compounds for Hall measurements and the study of lead telluride doping with barium flouride
The first part of the work dealt with the application of lithographical techniques to fabricate Hall geometry of IV-VI films grown on (111) BaF_2 substrates. A previous study of In diffusion in PbTe films confirmed the viability of using In as a metallic contact. During the lithographic process, some solutions were implemented to resolve the problems generat
Publicado em: 2009
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5. Alloying in GeSi:Si (001) epitaxial nanocrystals / Formação de ligas em nanocristais epitaxiais de GeSi:Si (001)
The structural and electronic properties of nanoscale materials strongly depend on the chemical composition, as well as their size and shape. A big variety of morphologies can be achieved by controlling the experimental conditions during the epitaxial growth of Ge on a Si(001) substrate. In particular, three-dimensional islands with well defined size and sha
Publicado em: 2007
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6. Propriedades Ópticas de Semicondutores Orgânicos à Base de Polímeros Emissores de Luz / Optical proprieties of organic semiconductors based on light emitting polymers.
In this work, we studied the optical proprieties of absorption and emission of luminescent conjugated polymers based on poly(p-phenylene vinylene) (PPV). This material was processed in thin films by casting, spin-coating, self-assembled (SA) e Langmuir-Blodgett (LB) techniques, available in the Grupo de Polímeros Bernhard Gross, where the samples were chara
Publicado em: 2001
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7. Simulação da cinetica do crescimento de pontos quanticos semicondutores em vidros
The growth kinetics of pontos quânticos (QD) in a vitreous matrix is important because its linear and non linear optical properties depends on their sizes and dispersion. QD s are fabricated by melting the semiconductors elements together with the vitreous matrix. After melting, the glass is submitted to a thermal treatment to lower temperatures, (500- 600�
Publicado em: 2000
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8. Propriedades eletrônicas e estruturais de defeitos em Bulk e superfície de semicondutores / Electronic and structural properties of bulk and surface defects in semiconductor
As propriedades eletrônicas e estruturais de defeitos em bulk e superfície de semicondutores são estudadas através de cálculos de primeiros princípios. Apresentamos um estudo detalhado para as relaxações e distorções para diferentes estados de carga da vacância em Ge. Nosso principal resultado é que a vacância em Ge não é um sistema de U-negat
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 20/12/1999
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9. Camada epitaxial de INP : Zn Passivada por hidrogenio
This work is the first part of a project for the fabrication of low-dirnensional free carrier systems in semiconductors using hydrogen passivation. We present a systematic study of hydrogenation in InP:Zn epitaxiallayers. The para11el plate reactor was used to create a hydrogen plasma for hydrogenation of semiconductors. Zn passivation by hydrogen in lnP was
Publicado em: 1998
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10. Steady-state photocarrier grating techique / Técnica de grade de fotoportadores em estado estacionário
In this work we present a new and simple technique to measure transport and kinetic properties in photoconductive insulator semiconductors. Important properties as diffusion length and mobility-lifetime product of hydrogenated amorphous silicon (a-SI:h) was determined. This technique is based on the effect of a steady-state photocarrier grating concentration
Publicado em: 1994
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11. Study of incorporations of donor impurities in III-V semiconductor structures grown by molecular beam epitaxy. / Estudo de incorporações de impurezas doadoras em estruturas semicondutoras III-V crescidas por epitaxia por feixes moleculares.
III-V semiconductor samples were grown using the Molecular beam epitaxy technique, the electrical properties of the GaAs structures planar doped with silicon were investigated as well as the Silicon saturation and diffusion in these samles. The optcal and electrical properties of structures planar doped with Selenium were analyzed using the Capacitance Volta
Publicado em: 1993