http://publicationslist.org/data/l.m.redondo/atom.xmlLuis Redondo's Publications ListLuis Redondohttp://publicationslist.org/l.m.redondo$basepathfavicon.icoRecent additions to Luis Redondo's PublicationsList.org pagehttp://publicationslist.org/publications.png2008-02-27T21:19:21Zhttp://publicationslist.org/l.m.redondo/refid362008-01-07T09:23:48ZSolid-state modulator for high-voltage positive or negative repetitive pulsesL M Redondo, J Fernando Silva (2008) <i>IEEE Transactions on Power Electronics (submitted in January 2008)</i> : <br/>http://publicationslist.org/l.m.redondo/refid292007-10-15T11:42:13ZPerturbed Angular Correlations and Electron Channeling Solid State Physics Experiments at ISOLDETo be initiated in 1-Nov-2007<br/><br/> (2007) <i>POCI/FP/81921/2007, Participating Scientist in the research project (10%), Funded in 60.000 Euros by the Portuguese Technology and Science Foundation (FCT) </i><br/>http://publicationslist.org/l.m.redondo/refid72007-10-03T11:57:15ZA low-cost, accurate and non-intercepting continuous method for beam current measurements in a High-Current Ion ImplanterL M Redondo, J Rocha, J C Soares (2007) <i>Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms (Accepted for publication in September 2007)</i> : <br/>http://publicationslist.org/l.m.redondo/refid162007-10-01T12:18:21ZRepetitive all-solid-state pulse Marx type generator with energy recovery clamp circuit for inductive loadsA newly developed Marx type circuit topology that achieves both output-voltage multiplication and energy recovery, which has been developed for inductive load applications, namely Electromagnetic metal Forming (EMF), based on an all-solid-state Marx type generator, is described.
The proposed circuit takes advantage on the power semiconductor switches intensive use, replacing the conventional Marx...<br/><br/>L M Redondo, M T Pereira (2007) <i>The 34th IEEE International Conference on Plasma Science and the 16th IEEE International Pulsed Power Conference </i> <br/>http://publicationslist.org/l.m.redondo/refid152007-10-01T12:24:20ZModular pulsed generator for kV and kHz applications based on forward converters associationThe operation of a modular generator topology, developed for kHz and kV pulsed applications, is presented. The proposed generator uses individual modules each one consisting of a pulse circuit based on a modified forward converter topology, with the secondary windings series connected, delivering a fraction of the total voltage. A laboratorial prototype with three 5 kV modules, 800 V semiconductor...<br/><br/>L M Redondo, J Fernando Silva, E Margato (2007) <i>EPE 2007 - 12th European Conference on Power Electronics and Applications </i> <br/>http://publicationslist.org/l.m.redondo/refid172007-10-01T12:23:43ZSolid-state Marx generator design with an energy recovery reset circuit for output transformer associationIn this paper the circuit topology of a hybrid fully integrated solid-state Marx generator circuit, developed for kHz and kV applications, is presented and analysed. The proposed circuit uses only power semiconductor switches to increase the performance, being designed with a magnetizing energy reset circuit that enables the use of an output pulse transformer, which recovers the transformer magnet...<br/><br/>L M Redondo, J Fernando Silva, P Tavares, E Margato (2007) <i>38th Annual IEEE Power Electronics Specialists Conference</i> <br/>http://publicationslist.org/l.m.redondo/refid22007-10-03T17:01:25ZPulse shape improvement in core-type high-voltage pulse transformers with auxiliary windingsNowadays, high-voltage pulsed power based technologies are rapidly emerging as a key to efficient and flexible use of electrical power for many industrial applications. One of the most important elements in high-voltage pulse generating circuit technology is the transformer, generally used to further increase the pulse output voltage level. However, its non-ideal behavior has significant influence...<br/><br/>L M Redondo, J Fernando Silva, E Margato (2007) <i>IEEE Transactions on Magnetics</i> 43: 5 1973-1982<br/>http://publicationslist.org/l.m.redondo/refid352007-10-23T15:46:49ZFlyback versus Forward switching power supply topologies for pulsed power applicationsL M Redondo, J Fernando Silva (2007) <i>Transactions on Plasma Science (submitted in September 2007)</i> : <br/>http://publicationslist.org/l.m.redondo/refid342007-10-23T15:40:28ZMass spectrometry for precise isotope implantation in a High-Current Ion Implanter
L M Redondo, J Rocha, J C Soares (2007) <i>Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms (Submitted in October 2007)</i> : <br/>http://publicationslist.org/l.m.redondo/refid182007-10-01T12:30:06ZIsolated Autonomous Capacitive Power Supplies to Trigger Floating Semiconductors in a Marx GeneratorThis paper reports the development of isolated autonomous capacitive power supplies to charge each drive circuit of the high voltage floating semiconductor stage in a solid-state Marx Generator. The circuit takes advantage of an auxiliary
capacitor, charged in series with the main energy storage capacitor in each Marx generator stage, to supply the optic-fibre isolated gate drive circuit of the s...<br/><br/>Hiren Canacsinh, L M Redondo, J Fernando Silva (2007) <i>ISIE 2007 - 2007 IEEE International Symposium on Industrial Electronics</i> <br/>http://publicationslist.org/l.m.redondo/refid12007-10-03T17:01:15ZAnalysis of a modular generator for high-voltage, high-frequency
pulsed applications, using low voltage semiconductors (<1 kV)
and series connected step-up (1:10) transformersThis article discusses the operation of a modular generator topology, which has been developed for high-frequency (kHz), high-voltage (kV) pulsed applications. The proposed generator uses individual modules, each one consisting of a pulse circuit based on a modified forward converter, which takes advantage of the required low duty cycle to operate with a low voltage clamp reset circuit for the ste...<br/><br/>L M Redondo, J Fernando Silva, E Margato (2007) <i>Review of Scientific Instruments</i> 78: 034702 7<br/>http://publicationslist.org/l.m.redondo/refid242007-10-15T11:39:38ZNegative target voltage modulator development for the on-line isotope separator ISOLDEThe On-Line Isotope Mass Separator ISOLDE is a facility dedicated to the production of a large variety of radioactive ion beams for many different experiments in the fields of nuclear and atomic physics, solid-state physics, materials science and life sciences. The facility is located at the Proton-Synchrotron Booster (PSB) of the European Organisation for Nuclear Research CERN.
The ion source ...<br/><br/> (2007) <i>POCI/FP/81932/2007, Responsible Scientist for the research project (35%). Funded in 25.000 Euros by the Portuguese Technology and Science Foundation (FCT). </i><br/>http://publicationslist.org/l.m.redondo/refid282007-10-01T16:15:42ZTechnical and scientific consultant with LUSOFORMA, a Portuguese aluminium foil packages industry, for developing an efficient solid-state pulsed power prototype for Electromagnetic FormingL M Redondo, Responsible Scientist (2006) <i></i><br/>http://publicationslist.org/l.m.redondo/refid332007-10-15T17:01:47ZInternational Call for Applications for 1000 PhD research positions
in Portuguese scientific institutions - Two
L M Redondo (2006) <i>FCT/219/2006, Principal Investigator for this project. The project was granted two post-doctoral positions from the Portuguese Technology and Science Foundation (FCT), for 5 years in the CFNUL; in Nuclear Instrumentation and in Applied Nuclear Physics.</i><br/>http://publicationslist.org/l.m.redondo/refid62007-10-01T00:22:57ZHigh-voltage, high-frequency generator, using only low voltage power semiconductors in the capacitors charging circuits, capable of resetting a pulse transformerL M Redondo, J Fernando Silva, E Margato, P Tavares (2006) <i>Intellectual Property National Institute (INPI) Bulletin, February 2006, Portuguese National Patent n. º PT 103 150</i><br/>http://publicationslist.org/l.m.redondo/refid262007-10-15T11:41:40ZCoupling catalysts and nonthermal plasma for low temperature decomposition of organic volatile compoundsRegulations on the allowable emissions of toxic gases have resulted in increasing interest in the development of
energy efficient methods for remediation.
The typical concentration range of concern in air-pollution problems is of the order of several tenths to several
hundredths ppmv. For this range of concentration, both temperature activated catalysts and plasma based methods
have been used ...<br/><br/> (2006) <i>PTDC/EQU-EQU/65126/2006, Participating Scientist in the research project (10%). Funded in 125.000 Euros by the Portuguese Technology and Science Foundation (FCT). </i><br/>http://publicationslist.org/l.m.redondo/refid252007-10-01T16:06:23ZTechnical and scientific consultant at the Ion Beam Laboratory, from ITN (Nuclear and Technological Institute, Sacavém, Portugal), in the fields of instrumentation and physics:
a) 210 keV High-Current Ion Implanter installation, operation and developing, since 1992;
b) 2.5 MeV Van de Graaff accelerator automatic control project coordination, since 2006;
c) 3 MeV Tandem ion sources installation, operation and developing, since 2006.
L M Redondo, Responsible Scientist (2006) <i></i><br/>http://publicationslist.org/l.m.redondo/refid192007-10-01T12:34:07ZHigh-voltage, high-frequency Marx-bank type pulse generator using integrated power semiconductor half-bridgesThis paper discusses the operation of an all silicon-based solution for the conventional Marx generator circuit, which has been developed for high-frequency (kHz), high-voltage (kV) applications needing rectangular pulses. The conventional Marx generator, for high-voltage pulsed applications, uses passive power components (inductors or resistors), to supply the energy storage capacitors. This solu...<br/><br/>L M Redondo, J Fernando Silva, P Tavares, E Margato (2005) <i>2005 EPE 11th European Conference on Power Electronics and Applications</i> P1-P8<br/>http://publicationslist.org/l.m.redondo/refid302007-10-15T11:49:54ZPerturbed Angular Correlations and Electron Channeling Solid State Physics Experiments at ISOLDE (2005) <i>PTDC/FP/63911/2005, Participating Scientist in the research project (10%). Funded in 60.000 Euros by the Portuguese Technology and Science Foundation (FCT).</i><br/>http://publicationslist.org/l.m.redondo/refid202007-10-01T12:38:30ZAll Silicon Marx-bank topology for high-voltage, high-frequency rectangular pulsesThis paper discusses the operation of a fully integrated solid-state Marx generator circuit, which has been developed for high-frequency (kHz), high-voltage (kV) applications needing rectangular pulses. The conventional Marx generator, used for high-voltage pulsed applications, uses inductors, or resistors, to supply the charging capacitors voltage, which has the disadvantages of size, power loss ...<br/><br/>L M Redondo, J Fernando Silva, P Tavares, E Margato (2005) <i>2005 IEEE 36th Annual Power Electronics Specialists Conference, PESC</i> 1170-1174<br/>http://publicationslist.org/l.m.redondo/refid312007-10-15T11:49:09Z Perturbed Angular Correlations and Electron Channeling Solid State Physics Experiments at ISOLDE (2005) <i>POCTI-FP-63435-2005, Participating Scientist in the research project (50%). Funded in 45.000 Euros by the Portuguese Technology and Science Foundation (FCT).</i><br/>http://publicationslist.org/l.m.redondo/refid222007-10-01T16:09:13ZHigh-Voltage Pulsed Modulators for Plasma Immersion Ion Implantation - Low semiconductors applicationThis work proposes power electronic converter topologies and transformer configurations to achieve almost rectangular high voltage (several kV) pulses. Both the power converters and transformer configuration allow the definition of methods to obtain High Voltage Pulsed Generators (HVPG) for Plasma Immersion Ion Implantation (PIII) applications, using low voltage (<1kV), non-series connected semico...<br/><br/>L M Redondo (2004) <br/>http://publicationslist.org/l.m.redondo/refid42007-10-03T17:01:50ZProgress on high-voltage pulse generators, using low voltage semiconductors (<1kV),
designed for Plasma Immersion Ion Implantation (PIII)
modular concept on high-voltage pulse generators, under development for future use in facilities for plasma immersion ion implantation, is presented. The generator proposed uses individual modules, each one consisting of a pulse circuit based on a step-up transformer; the secondary of each step-up transformer is connected in series. Each step-up transformer delivers a fraction of the total voltag...<br/><br/>L M Redondo, N Pinhão, E Margato, J Fernando Silva (2002) <i>Surface and Coatings Technology</i> 156: 1-3 61-65<br/>http://publicationslist.org/l.m.redondo/refid32007-10-03T17:01:34ZRise time reduction in high-voltage pulse transformers using auxiliary windingsToday high-voltage pulses are reaching more fields of application. High-voltage pulse transformers are often used in association with high-voltage pulse generating circuits to further increase the pulse output voltage level. However, because of the transformer parasitic elements involved, the transformer is the critical device in shaping the rising characteristics of the output pulse. One of the t...<br/><br/>L M Redondo, E Margato, J Fernando Silva (2002) <i>IEEE Transactions on Power Electronics</i> 17: 2 196-206<br/>http://publicationslist.org/l.m.redondo/refid52007-10-03T17:01:44ZA new method to build a High Voltage Pulse Supply using only semiconductor switches for plasma immersion ion implantationA new method to obtain high voltage (kV) pulses suitable for a plasma immersion ion implantation (PIII) facility is presented. The circuit proposed is based on a step-up transformer with a constant flux reset clamp circuit that takes advantage of the low duty ratio required to reduce the voltage stress on all semiconductor switches. An initial prototype was assembled with 800-V semiconductor switc...<br/><br/>L M Redondo, E Margato, J Fernando Silva (2001) <i>Surface and Coatings Technology</i> 136: 1-3 51-54<br/>http://publicationslist.org/l.m.redondo/refid322007-10-15T11:52:27Z50kV/1A pulse generator for plasma immersion ion implantation (2001) <i>POCTI/ESE/38963/2001, Participating Scientist in the research project (50%). Funded in 70.000 Euros by the Portuguese Technology and Science Foundation (FCT).</i><br/>http://publicationslist.org/l.m.redondo/refid212007-10-01T12:45:53ZLow-voltage semiconductor topology for kV pulse generation using a leakage flux corrected step-up transformerThis paper introduces a new circuit to obtain high voltage (kV) pulsed power supplies suitable for plasma ion implantation. Using a step-up transformer with a leakage flux reduction winding, and taking advantage of the low duty ratio required, 800 V semiconductor switches can be used to obtain 5 kV 10 kHz pulses. Theoretical and experimental results are presented.<br/><br/>L M Redondo, E Margato, J Fernando Silva (2000) <i>IEEE 31st Annual Power Electronics Specialists Conference, PESC 00 </i> 326-331 <br/>http://publicationslist.org/l.m.redondo/refid82007-10-03T17:01:57ZGMR in high fluence ion implanted granular thin filmsWe report on the magnetic and magnetoresistive (MR) properties of granular materials obtained by implantation of high fluences (from 1 × 1016 to 1.8 × 1017 ions/cm2) of Fe and Co ions into Cu and Ag thin films. The local microstructure vs. implantation doses and posterior thermal treatment is discussed to obtain MR values of practical relevance. MR measurements up to very high fields (32 T) are ...<br/><br/>J B Sousa, M M Pereira de Azevedoa, M S Rogalskia, Yu G Pogorelova, L M Redondo, C M de Jesus, J G Marques, M F da Silva, J C Soares, J C Oussetc, E Snoeckd
(1999) <i>Journal of Magnetism and Magnetic Materials </i> 196-197: 13-17<br/>http://publicationslist.org/l.m.redondo/refid92007-10-03T17:02:07ZIon implantation of microcrystalline silicon for low process temperature top gate thin film transistorsIon implantation of phosphorus was used to dope amorphous and microcrystalline silicon with the aim of achieving a low-temperature, self-aligned process for forming n1 contacts to top-gate thin-film transistors. Amorphous and microcrystalline films made with both RF glow discharge and hot-wire chemical vapor deposition were implanted. The effect of the dose, energy and implantation temperature and...<br/><br/>V Chu, H Silva, L M Redondo, C Jesus, M F Silva, J C Soares, J P Conde (1999) <i>Thin Solid Films</i> 337: 1 203-207<br/>http://publicationslist.org/l.m.redondo/refid102007-10-01T10:42:49ZGiant Magnetoresistance behaviour of granular Fe and Co Implanted Ag Thin FilmsThe magnetoresistive behavior of granular thin films prepared by Fe and Co implantation in Ag thin films is reported. Ag thin films (~ 2000 Å) were deposited by evaporation or laser ablation onto Si and SiO2 substrates and implanted with Fe or Co at fluences up to 1017 at. %/cm2. The magnetoresistive response obtained after implantation was found to increase with the implanted fluence. An increas...<br/><br/>J C Soares, L M Redondo, C M Jesus, J G Marques, M F Silva, M M P Azevedo, J A Mendes, M S Rogalski, J B Sousa (1998) <i>Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films </i> 16: 3 1812-1816<br/>http://publicationslist.org/l.m.redondo/refid132007-10-03T17:02:39ZLattice site location and annealing behaviour of W implanted TiO2The implantation damage and lattice site location of W in TiO2 (rutile) was studied using the Rutherford backscattering technique in the channeling mode (RBS-C). The W ions were implanted at room temperature with fluences in the range of 1015 to 1017/cm2 into both 1 0 0 and 0 0 1 oriented single crystals. The implanted region becomes completely disordered for W doses higher than 1016/cm2. After an...<br/><br/>E Alves, L M Redondo, R Fromknecht, O Meyer, R C Da Silva (1998) <i>Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms </i> 136-138: 442-446<br/>http://publicationslist.org/l.m.redondo/refid122007-10-03T17:02:32ZHigh flux 56Fe+ and 57Fe+ implantations for GMR applications
The magnetoresistive behaviour of granular thin films prepared by 56Fe and 57Fe ion implantation into Ag thin films with fluences up to 8 × 1016 at./cm2 is reported. The implantation produced both small and large Fe clusters, with the large clusters being dominant for high fluences. A significant magnetoresistive response of the films was obtained for fluences above 6 × 1016 Fe/cm2, reaching val...<br/><br/>L M Redondo, C M de Jesus, J G Marques, M F da Silva, J C Soares, M M Pereira de Azevedo, J A Mendes, M S Rogalski, J B Sousa (1998) <i>Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms </i> 139: 1-4 350-354<br/>http://publicationslist.org/l.m.redondo/refid112007-10-03T17:02:15ZAnalysis of the elements sputtered during the lanthanum implantation in stainless steels
The evidence of the modification of the surface structure of the AISI-304 stainless steel during the implantation of lanthanum makes the analysis of the sputtered elements very interesting. Those sputtered elements are deposited on a carbon sheet placed in front of the steel being implanted, and studied by means of RBS and PIXE, together with the implanted specimens. Besides, the protective effect...<br/><br/>F J Ager, M A Respaldiza, A Paúl, J A Odriozola, J M Lobato, M F da Silva, L M Redondo, J C Soares (1998) <i>Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms </i> 139: 1-4 344-349<br/>http://publicationslist.org/l.m.redondo/refid142007-10-03T17:02:46ZMagnetization and magnetoresistance in Fe-ion-implanted Cu and Ag thin filmsDiluted granular films of Cu---Fe and Ag---Fe (iron content 2%) were produced using 57Fe ion implantation on Cu(Ag) films previously grown by laser ablation. Conversion electron Mössbauer spectroscopy shows that the implanted Fe forms either very small clusters (up to a few atoms) or large iron α-phase particles. These structural characteristics directly reflect on the magnetization, which exhi...<br/><br/>M M Pereira de Azevedo, J B Sousa, J A Mendes, B G Almeida, M S Rogalski, Yu G Pogorelov, I Bibicu, L M Redondo, M F da Silva, C M Jesus, J G Marques, J C Soares (1997) <i>Journal of Magnetism and Magnetic Materials </i> 173: 3 230-240<br/>http://publicationslist.org/l.m.redondo/refid232007-10-01T16:09:47ZHigh-Current Ion Implanter - Installation and OperationL M. Redondo (1996) <br/>http://publicationslist.org/l.m.redondo/refid272007-10-01T16:13:06ZAutomation of a two axis GoniometerL M Redondo (1992) <i>Lisbon Engineering Superior Institute, ISEL, Degree in electrical and automation engineer</i><br/>