Ellipsometry
Mostrando 13-24 de 38 artigos, teses e dissertações.
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13. Estudo sobre a adsorção do fluido de perfuração salgado contendo polímeros sobre SiO2
Polysaccharide-based drilling fluids have been often applied in horizontal wells of petroleum reservoirs in Campos, Rio de Janeiro. The present study aimed to understand the mechanism of adsorption and desorption of the drill-in fluid, xanthan, modified starch and lubricant on SiO2 by means of ellipsometry. The effect of pH and brine on the mean thickness (D
Química Nova. Publicado em: 2007-08
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14. Caracterização de filmes finos de óxido de silício depositados em um reator HD-PECVD a partir de TEOS a ultra baixa temperatura. / Characterization of silicon dioxide thin films deposited in a HD-PECVD reactor from TEOS at ultra low temperature.
This work reports on the results obtained from high-density plasma enhanced chemical vapor deposited silicon oxide films at ultra low temperature, i.e. 30°C, using TEOS vapor as the silicon source oxidized with assistance of argon. The objectives of this work are: first, understand the phenomena that conducts the chemical vapor deposition in high density re
Publicado em: 2007
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15. Fabricação e caracterização de Guia de Onda Polimerica a base de PMMA modificado por plasma de CHF3 / Polymeric optical waveguides fabricated by plasma fluorination process
Polymeric optical devices have been studied in communication and interconnection optics due to the intrinsic versatility of polymers molecular structure, that allows advantageous refractive index modeling for core and cladding, and also to their easy fabrication process or patterning capability. PMMA, polymethylmetacrylate, shows the best optical properties
Publicado em: 2007
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16. Modificações induzidas por ions de alta energia em filmes finos de organosilicones sintetizados por PECVD / Modifications induced by high energy ions in organosilicones thin films syntesized by PECVD
Thin films of polysiloxanes, polysilazanes and polycarbosilanes, synthesized by Plasma Enhanced Chemical Vapor Deposition (PECVD), were irradiated with 170 keV He + , Ne + , Ar + and Kr + ions, at 170 keV at fluences of 1x10 14 , 5 x10 14 , 1x10 15 , 5x10 15 and 1 x10 16 ions/cm -2 . The irradiation promoted significant modifications in the atomic compositio
Publicado em: 2007
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17. Modifications induced by high energy ions in organosilicones thin films syntesized by PECVD / Modificações induzidas por ions de alta energia em filmes finos de organosilicones sintetizados por PECVD
Thin films of polysiloxanes, polysilazanes and polycarbosilanes, synthesized by Plasma Enhanced Chemical Vapor Deposition (PECVD), were irradiated with 170 keV He + , Ne + , Ar + and Kr + ions, at 170 keV at fluences of 1x10 14 , 5 x10 14 , 1x10 15 , 5x10 15 and 1 x10 16 ions/cm -2 . The irradiation promoted significant modifications in the atomic compositio
Publicado em: 2007
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18. Efeitos de ordenamento na polarização da luz emitida por filmes de polímeros semicondutores
Nesse trabalho apresentamos um estudo das propriedades ópticas de filmes ordenados e não ordenados de poli(p-fenileno vinileno) (PPV). Investigamos a influência do ordenamento molecular no estado de polarização da luz emitida por filmes poliméricos de PPV. Para este fim, realizamos um experimento de elipsometria, no escopo da teoria de Stokes para o ca
Publicado em: 2007
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19. Efeitos de ordenamento na polarizaÃÃo da luz emitida por filmes de polÃmeros semicondutores
Nesse trabalho apresentamos um estudo das propriedades Ãpticas de filmes ordenados e nÃo ordenados de poli(p-fenileno vinileno) (PPV). Investigamos a influÃncia do ordenamento molecular no estado de polarizaÃÃo da luz emitida por filmes polimÃricos de PPV. Para este fim, realizamos um experimento de elipsometria, no escopo da teoria de Stokes para o ca
Publicado em: 2007
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20. Semiconductor characteristics of Nd doped PbO-Bi2O3-Ga2O3 films
In this work optical and semiconductor characteristics of gallium oxide based thin films are studied. This material has important electro-optic applications and offers possibilities for semiconductor applications in heavy metal oxide semiconductor technology. In this study thin films of PbO-Bi2O3-Ga2O3 were deposited by reactive sputtering. Two targets with
Brazilian Journal of Physics. Publicado em: 2006-06
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21. Estudo das interações entre enzimas e polímeros: efeito do poli(etileno glicol) na atividade e na conformação estrutural de enzimas. Adsorção de enzimas sobre superfícies sólidas / Study on the interactions between enzymes and polymers: Influence of polyethylene glycol on the activity and conformation of enzymes. Adsorption of enzymes onto solid surfaces
This work aimed to investigate the interactions between enzymes and polymers in solution and also the adsorption behavior of these enzymes on solid surfaces. For that reason it was divided into two parts. In the first part, the influence of poly(ethylene glycol) (PEG), a polymer considered inert and utilized in several biotechnological processes, on the enzy
Publicado em: 2006
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22. Tecnologia LOCOS utilizando nitretos de silicio depositados por ECR-CVD / LOCOS technology using silicon nitride deposited by ECR-CVD
Silicon nitride (SiNx) insulators for LOCOS applications have been deposited by RP/RTCVD and ECR-CVD at room temperature, at low pressure (5mTorr), with N2 flows of 2.5, 5, 10 and 20sccm with fixed SiH4/Ar flows of 200/20sccm with a microwave power of 1000W on SiO2-Pad/Si and Si substrates. SiNx/Si structures were obtained to analyze the physical characteris
Publicado em: 2005
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23. Interaction between biomolecules and solid surfaces / Interação entre a enzima enolase e superfícies sólidas
This work aimed to compare the adsorption behavior of enolase (2-phospho-D- glycerate hydrolase) onto hydrophilic (silicon wafers and amino-terminated surfaces (APS)) and hydrophobic planar substrates (polystyrene (PS) film, TMCS). The effect of the substrate shape (planar x spherical) was also studied. The spherical substrates were glass beads, native and m
Publicado em: 2004
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24. Spectroscopy studies of 4H-SiC
Calculations of the total dielectric functions and the optical bandgap energy (OBGE) of 4HSiC were performed by the full-potential linear muffin-tin-orbital method. The results are compared to spectroscopic ellipsometry dielectric measurements agreeing closely over in a wide range of energies. The obtained theoretical value of the (OBGE) agrees very closely
Materials Research. Publicado em: 2003-01