Encontrados 30 documentos, a visualizar página 1 de 3
The effect of argon plasma treatment on the permeation barrier properties of si...
Majee, Subimal; Cerqueira, M. F.; Tondelier, D.; Geffroy, B.; Bonnassieux, Y.; Alpuim, P.; Bourée, J. E.In this work we produce and study silicon nitride (SiNx) thin films deposited by Hot Wire Chemical Vapor Depo- sition (HW-CVD) to be used as encapsulation barriers for flexible organic photovoltaic cells fabricated on poly- ethylene terephthalate (PET) substrates in order to increase their shelf lifetime. We report on the results of SiNx double-layers and on the equivalent double-layer stack where an Ar-plasma ...
Study on excimer laser irradiation for controlled dehydrogenation and crystalli...
Gontad, F.; Filonovich, Sergey; Cerqueira, M. F.; Alpuim, P.; Chiussi, StefanoWe report on the excimer laser annealing (ELA) induced temperature gradients, allowing controlled crystal-lization and dehydrogenation of boron-doped a-Si:H/nc-Si:H multilayers. Depth of the dehydrogenation and crystallization process has been studied numerically and experimentally, showing that temperatures below the monohydride decomposition can be used and that significant changes of the doping profile can be ...
FEM numerical analysis of excimer laser induced modification in alternating mul...
Conde, J. C.; Martín, E.; Stefanov, S.; Chiussi, S.; Alpuim, P.UV excimer laser annealing (UV-ELA) is an alternative annealing process that, during the last few years, has gained enormous importance for the CMOS nano-electronic technologies, with the ability to provide films and alloys with electrical and optical properties to fit the desired device performance. The UV-ELA of amorphous (a-) and/or doped nano-crystalline (nc-) silicon films is based on the rapid (nanosecond...
Nanoporous alumina templates : anodisation and mechanical characterisation
Samantilleke, A. P.; Carneiro, Joaquim A. O.; Alpuim, P.; Teixeira, Vasco M. P.; Thuy, Tran Thi ThuDue to applications in electronics, optoelectronics, energy storage, photocatalysis, photonics and biosensors/biomaterials, interest in onedimensional nanostructures has grown significantly during the last decade. The use of nanoporous templates as matrices for fabrication of nanostructures is now commonplace in microelectronics technology. Studies on semiconductors and dielectrics have introduced nanoporous an...
Study of the piezoresistivity of doped nanocrystalline silicon thin films
Gaspar, J.; Gieschke, P.; Ehling, C.; Kistner, J.; Gonçalves, N. J.; Vasilevskiy, Mikhail; Paul, O.; Alpuim, P.The piezoresistive response of n- and p-type hydrogenated nanocrystalline silicon thin films, deposited by hot-wire (HW) and plasma-enhanced chemical vapor deposition (PECVD) on thermally oxidized silicon wafers, has been studied using four-point bending tests. The piezoresistive gauge factor (GF) was measured on patterned thin-film micro-resistors rotated by an angle θ with respect to the principal strain axis...
High-rate deposition of nano-crystalline silicon thin films on plastics
Marins, Emílio Sérgio; Guduru, Virendra; Ribeiro, Miguel; Cerqueira, M. F.; Bouattour, Ali; Alpuim, P.Nanocrystalline silicon (nc-Si:H) is commonly used in the bottom cell of tandem solar cells. With an indirect bandgap, nc-Si:H requires thicker (∼1 µm) films for efficient light harvesting than amorphous Si (a-Si:H) does. Therefore, thin-film high deposition rates are crucial for further cost reduction of highly efficient a–Si:H based photovoltaic technology. Plastic substrates allow for further cost reduction ...
Piezoresistive silicon thin film sensor array for biomedical applications
Alpuim, P.; Correia, Vítor; Marins, Emílio Sérgio; Rocha, J. G.; Trindade, Isabel; Lanceros-Méndez, S.N-type hydrogenated nanocrystalline silicon thin film piezoresistors, with gauge factor −28, were deposited on rugged and flexible polyimide foils by Hot-wire chemical vapor deposition using a tantalum filament heated to 1750 °C. The piezoresistive response under cyclic quasi-static and dynamical (up to 100 Hz) load conditions is reported. Test structures, consisting of microresistors having lateral dimensions ...
Erbium-doped nanocrystalline silicon thin films produced by RF sputtering : ann...
Cerqueira, M. F.; Monteiro, T.; Soares, Manuel Jorge; Kozanecki, A.; Alpuim, P.; Alves, E.In order to improve the transparent contact layer in amorphous silicon solar cells fabricated on low-temperature plastic substrates, Al and Ga doped ZnO films were deposited at room temperature on plastic and glass and their optical, electronic and structural properties were correlated and optimized. Aiming to explore light trapping effects, plastic substrates were laser textured and their haze and total transm...
Structural and photoluminescence studies of erbium implanted nanocrystalline si...
Cerqueira, M. F.; Alpuim, P.; Filonovich, Sergey; Alves, E.; Rolo, Anabela G.; Andrês, G.; Soares, J.; Kozanecki, A.Hydrogenated amorphous and nanocrystalline silicon thin films deposited by Hot Wire (HW) and Radio-Frequency Plasma-Enhanced (RF) Chemical Vapor Deposition were Er-bium-implanted. Their pre-implantation structural properties and post-implantation optical properties were studied and cor-related. After one-hour annealing at 150ºC in nitrogen atmos-phere only amorphous films showed photoluminescence (PL) activity ...
Photoluminescence of nc-Si:Er thin films obtained by physical and chemical vapo...
Cerqueira, M. F.; Losurdo, M.; Stepikhova, M.; Alpuim, P.; Andrês, G.; Kozanecki, A.; Soares, Manuel Jorge; Peres, M.Erbium doped nanocrystalline silicon (nc-Si:Er) thin films were produced by reactive magnetron rf sputtering and by Er ion implantation into chemical vapor deposited Si films. The structure and chemical composition of films obtained by the two approaches were studied by micro-Raman scattering, spectroscopic ellipsometry and Rutherford backscattering techniques. Variation of deposition parameters was used to dep...
| Financiadores do RCAAP | |||||||
|
|
|
|
|
|
||