b d Morawiec, S.a b, Mendes Filonovich Mateus Mirabella Aguas Ferreira Simone Fortunato Martins Priolo Crupi M. J. a S. "
Photocurrent enhancement in thin a-Si:H solar cells via plasmonic light trapping."
Conference on Lasers and Electro-Optics Europe - Technical Digest. Vol. 2014-January. 2014.
AbstractPhotocurrent enhancement in thin a-Si:H solar cells due to the plasmonic light trapping is investigated, and correlated with the morphology and the optical properties of the selfassembled silver nanoparticles incorporated in the cells' back reflector. © 2014 Optical Society of America.
Meng, L., Macarico Martins A. R. "
Study of annealed indium tin oxide films prepared by rf reactive magnetron sputtering."
Materials Research Society Symposium - Proceedings. Vol. 388. 1995. 379-384.
AbstractTin doped indium oxide (ITO) films were deposited on glass substrates by rf reactive magnetron sputtering using a metallic alloy target (In-Sn, 90-10). The post-deposition annealing has been done for ITO films in air and the effect of annealing temperature on the electrical, optical and structural properties of ITO films was studied. It has been found that the increase of the annealing temperature will improve the film electrical properties. The resistivity of as-deposited film is about 1.3×10-1 Ω* cm and decreases down to 6.9×10-3 Ω* cm as the annealing temperature is increased up to 500°C. In addition, the annealing will also increase the film surface roughness which can improve the efficiency of amorphous silicon solar cells by increasing the amount of light trapping.
Mei, S.a, Yang Ferreira Martins J. a J. M. "
Aqueous tape casting of low-k cordierite substrate: The influence of glass content."
Materials Science Forum. 455-456 (2004): 168-171.
AbstractThick films of cordierite-based glass ceramics were prepared by aqueous tape casting from suspensions containing 80-wt% solids. The weight proportions of cordierite/glass ranged from 70/30 to 30/70 in order to investigate the effect of glass content on the rheological behaviour and on the microstructures and properties of the green tapes. Suspensions with 50 to 60-wt% glass content exhibited the lowest viscosity values among all the slurries investigated, while the green tape containing 30-wt% glass presented homogenous microstructures at both top and bottom surfaces, contrarily to the observations for the other compositions. The green densities increased with glass content. The sintered tapes (1150°C, 2h) containing 50 to 60-wt% glass exhibited the lowest values for the dielectric constant (∼5.2) and dielectric loss (∼0.002) at 1MHz.
Martins, R., Lavareda Soares Fortunato G. F. E. "
Detection limit of large area 1D thin film position sensitive detectors based in a-Si:H P.I.N. diodes."
Materials Research Society Symposium - Proceedings. Vol. 377. 1995. 791-796.
AbstractThe aim of this work is to provide the basis for the interpretation of the steady state lateral photoeffect observed in p-i-n a-Si:H 1D Thin Film Position Sensitive Detectors (1D TFPSD). The experimental data recorded in 1D TFPSD devices with different performances are compared with the predicted curves and the obtained correlation's discussed.
b b b b b b b Martins, R.a b, Carvalho Fortunato Maçarico Santos Baia Viera Guimarães N. a E. a. "
Effects of U.V. light on the transport properties of a-Si : H films during their growth."
Journal of Non-Crystalline Solids. 97-98 (1987): 1399-1402.
AbstractThe influence of U.V. light on the transport properties of a-Si : H films during its growth in a r.f. double chamber system was investigated by conductivity, optical absorption, I.R. absorption, spectral photoconductivity and X-ray diffraction measurements. It was concluded that the presence of U.V. light during the deposition process controls the way how hydrogen is incorporated in the structure as well as the impurity atoms. The microcrystalline films investigated present sharp peaks in the I.R. spectra. Both boron and phosphorus doped films show conductivities higher than 10 S cm-1 and estimated crystalline sizes of the order of 80 Å. © 1987.
Martins, R.a, Pereira Fortunato L. b E. c. "
Paper electronics: A challenge for the future."
Digest of Technical Papers - SID International Symposium. Vol. 44. 2013. 365-367.
AbstractIn this paper we report results concerning the use of paper as substrate and as an electronic component for the next generation of sustainable low cost electronic systems, where different examples of applications are given. © 2013 Society for Information Display.
Martins, R., Ferreira Fortunato I. E. "
Growth model of gas species produced by the hot-wire and hot-wire plasma-assisted techniques."
Key Engineering Materials. 230-232 (2002): 603-606.
AbstractThe model presented is based on the heat transfer and energy balance equations that rule the set of physical and chemical interactions that take place on the gas phase of a growth process, assuming that the deposition process occurs under laminar dynamic flow conditions (Knudsen number below 1). In these conditions, the chemistry and physics of the process involved in the growth mechanism of silicon thin films produced by the hot wire or the hot-wire plasma assisted technique can be proper derived by balance equations that supply information about how the plasma density, the gas dilution and the gas temperature influence the growth mechanism and the equilibrium of the concentration of species presented on the growth surface. The model developed establishes a relation between the abundance species formed and the parameters initiators of the process such as the filament temperature and the rf power density used.
Martins, R., Fantoni Vieira A. M. "
Tailoring defects on amorphous silicon pin devices."
Journal of Non-Crystalline Solids. 164-166 (1993): 671-674.
AbstractThis paper deals with a new model and structure able to tailor defects in pin devices. The model assumes the usual density of states profile, including donor and acceptor like states inside the mobility gap and has the capability to simulate the transient and steady state device behavior. The new structure is based in two interfacial defectous layers, located at the junctions, acting as "gettering" centers to tailor the defects. The role of the interlayer and its thickness on device performances will be also discussed. © 1993.