Boron Doping
Mostrando 1-11 de 11 artigos, teses e dissertações.
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1. Boron Doped Ultrananocrystalline Diamond Films on Porous Silicon: Morphological, Structural and Electrochemical Characterizations
Boron doped ultrananocrystalline diamond (BDUND) films were grown and characterized on porous silicon (PS) substrates. PS samples were prepared from n-type monocrystalline silicon wafers (100) with 1-20 Ω.cm of resistivity, by electrochemical etching, using HF-acetonitrile solution as electrolyte. BDUND films were grown by Hot Filament Chemical Vapor Deposi
Mat. Res.. Publicado em: 24/11/2015
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2. 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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3. Estudo da dopagem em nanotubos de carbono por espectroscopia Raman ressonante.
Doping of single wall carbon nanotubes with boron, nitrogen, phosphorous and sulfur was studied by resonance Raman spectroscopy. The doping atoms were inserted in the tube walls during synthesis, by using chemical vapor deposition, laser ablation and arc discharge methods. The analysis of the Raman spectra shows that the insertion of dopants generates tubes
Publicado em: 2009
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4. Estudo de Impurezas de Carbono em Nanoestruturas de BN
In this work, we performed an analysis of the structural and electronic stability of nanostructures of Boron Nitride (BN), such as layers, tubes and cones, when doped with Carbon, through first-principles calculations as implemented in code SIESTA. We found that substitutional doping of Carbon for either a single Boron or a single Nitrogen atom produces sign
Publicado em: 2008
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5. Contribuição para a sintese de diamante nanocristalino com dopagem de boro / Contribution towards the synthesis of boron doped nanocrystalline diamonds
This thesis presents a study of the growth and characterization of nano crystalline diamonds produced by the hot-filament chemical vapor deposition (CVD) with the introduction of boron during the growth process. Our objective was to produce samples with good electrical properties for field induced emission of electrons (FEE) to the vacuum. Characterization o
Publicado em: 2008
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6. Electroanalytical determination of nitrofurantoin (NFT) in drug and biological fluids using diamond electrode doped with boron / DeterminaÃÃo eletroanalÃtica de nitrofurantoÃna (NFT) em fÃrmaco e em fluido biolÃgico utilizando eletrodo de diamante dopado com boro
Este trabalho apresenta o estudo da quantificaÃÃo de nitrofurantoina (NFT) utilizando os filmes de diamante dopados com boro como material eletrÃdico. Estudos preliminares utilizando voltametria cÃclica (VC) mostraram que o mecanismo de reduÃÃo da nitrofurantoina (NFT) envolve adsorÃÃo e à influenciado pelo pH, o nÃvel de dopagem de boro no eletrod
Publicado em: 2008
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7. Contribuições ao desenvolvimento de filmes de diamante microcristalino dopados com enxofre / Contributions to the development of sulphur doped microcrystalline diamond films
We present in this work the development of grown diamond films with sulphur addition. They had been grown by chemical deposition from the vapor phase (diamond CVD) using reactors of the type hot filament. For the diamond attainment with conduction of the n-type, we diluted different concentrations of carbon disulfide (CS2) in ethyl alcohol, whose vapor was d
Publicado em: 2007
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8. Contribuição para a sintese de diamante com dopagens de boro, nitrogenio ou enxofre / Study of diamond doping with boron, sulphur and nitrogen
We studied the diamond doping processes with introduction of doping impurities during the diamond growth in the chemical vapor deposition (CVD) technique, using a hot-filament reactor. Our research focused the use of boron, nitrogen or sulphur atoms in order to obtain diamond films with semiconductor properties of electronic (n-type) or hole (p-type) current
Publicado em: 2004
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9. Boron doping of hydrogenated amorphous silicon prepared by rf-co-sputtering
This paper addresses the doping mechanism of amorphous semiconductors through the investigation of boron doped rf co-sputtered amorphous hydrogenated silicon. The activation energy and room temperature conductivity varied from 0.9 to 0.3 eV and from 10-12 to 10-4 Ohm-1 .cm-1, respectively, by ranging the boron concentration from 0 to 3 at.%. These ranges of
Brazilian Journal of Physics. Publicado em: 2002-06
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10. Ressonância paramagnética em germânio amorfo hidrogenado e silício microcristalino hidrogenado
In this thesis, we present for the first time light-induced electron spin resonance, LESR, measurements in a-Ge:H. The signal consists of two different centers: 1) assigned to electrons trapped in conduction band tails; and 2) holes trapped in valence band tails. We also have performed a recombination kinetics study based on the LESR time response. We have f
Publicado em: 2002
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11. Highly ordered amorphous silicon-carbon alloys obtained by RF PECVD
We have shown that close to stoichiometry RF PECVD amorphous silicon carbon alloys deposited under silane starving plasma conditions exhibit a tendency towards c-SiC chemical order. Motivated by this trend, we further explore the effect of increasing RF power and H2 dilution of the gaseous mixtures, aiming to obtain the amorphous counterpart of c-SiC by the
Brazilian Journal of Physics. Publicado em: 2000