Navegando por Autor "AGUIAR, V. A. P."

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Absorbed gamma-ray doses due to natural radionuclides in building materials
(2010-09-05) AGUIAR, V. A. P.; MEDINA, N. H.; MOREIRA, R. H.; Marcilei Aparecida Guazzelli
This work is devoted to the application of high-resolution gamma-ray spectrometry in the study of the effective dose coming from naturally occurring radionuclides, namely 40K, 232Th and 238U, present in building materials such as sand, cement, and granitic gravel. Four models were applied to estimate the effective dose and the hazard indices. The maximum estimated effective dose coming from the three reference rooms considered is 0.90(45) mSv/yr, and maximum internal hazard index is 0.77(24), both for the compact clay brick reference room. The principal gamma radiation sources are cement, sand and bricks. © 2010 American Institute of Physics.
Analyzing the influence of the angles of incidence on SEU and MBU events induced by low LET heavy ions in a 28-nm SRAM-based FPGA
(2017) TONFAT, J.; KASTENSMIDT, F. L.; ARTOLA, L.; HUBERT, G.; MEDINA, N. H.; ADDED, N.; AGUIAR, V. A. P.; AGUIRRE, F.; MACCHIONE, E. L. A.; Marcilei Aparecida Guazzelli
© 2016 IEEE.This work highlights the impact of low LET heavy ions particles on the reliability of 28-nm Bulk SRAM cells from 4rtix-7 FPGA. Radiation tests showed significant differences in he MBU cross section of configuration (CRAM) and BRAM memory cells under various angles of incidence. Radiation results re compared with simulations at transistor level by using the ioft error tool, MUSCA SEP3 (MUlti-SCAle Single Event henomenon Prediction Platform) coupled with circuit imulations with the aim to analyze the differences of upset ensitivity as a function of layout SRAM. This analysis leads to etermine the correct layout and technology used in the tested PGA. By using the detailed classification of MBU events, it is ossible to analyze the effectiveness of correction mechanisms of he FPGA configuration memory.
Analyzing the Influence of using Reconfiguration Memory Scrubber and Hardware Redundancy in a Radiation Hardened FPGA under Heavy Ions
(2018-09-05) OLIVEIRA, A.B. DE; BENEVENUT,I F.; BENITES, L. A. C.; RODRIGUES, G. S.; KASTENSMIDT, F. L.; ADDED, N.; AGUIAR, V. A. P.; MEDINA, N. H.; Marcilei Aparecida Guazzelli; DEBARGE, C.
© 2018 IEEE.This work investigates the influence of using the built-in configuration memory scrubber and triple modular hardware redundancy in the cross section of a radiation-hardened SRAM-based FPGA from NanoXplore. Different designs versions are investigated under heavy ions for the occurrence of transient errors, failures, and timeouts. The calculated dynamic cross-sections are in agreement with the expected order of magnitude of radiation hardened SRAM-based FPGAs. Results show that the most reliable configuration is using DSPs for the operational logic and applying full design redundancy combined with scrubbing.
Brazilian facilities to study radiation effects in electronic devices
(2013-05-05) MEDINA, N. H.; Santos, R. B. B.; SEIXAS, L. E.; TABACNIKS, M. H.; SILVEIRA, M. A. G.; ADDED, N.; AGUIAR, V. A. P.; AGUIRRE, F.; GIACOMINI, R.; MACCHIONE, E. L. A.; DE MELO, M. A. A.; OLIVEIRA, J. A.
Brazilian facilities to study radiation effects in electronic devices
(2013-09-27) MEDINA, N.H.; Marcilei Aparecida Guazzelli; ADDED, N.; AGUIAR, V. A. P.; AGUIRRE, F.; Renato Giacomini; MACCHIONE, E. L. A.; DE MELO, M. A. A.; OLIVEIRA, J. A.; Roberto Santos; SEIXAS, L. E.; TABACNIKS, M. H.
© 2013 IEEE.Three facilities in Brazil are being prepared and upgraded to test and to qualify electronic devices regarding their tolerance to TID and SEE: a 60 kV X-ray source, a 1.7 MV Pelletron accelerator for low energy proton beams and an 8 MV Pelletron accelerator that produces heavy ion beams. MOSFET transistors were exposed to 10-keV X-rays and to 2.4 MeV protons extracted into air. During irradiation, characteristic curves were continuously measured to monitor the circuit's behavior relative to the accumulated dose. 12C, 16O, 28Si, 35Cl and 63Cu heavy ion beams were also used mostly to test the experimental setup, and verify beam uniformity at low fluence conditions, equilibrium charge state, and carbon stripper foil durability. To test the setup for SEE, a pMOS transistor was irradiated with 63 MeV 63Cu ions scattered at 15° by a 275 μg/cm2 gold foil. The setups are now available for TID and SEE studies in electronic devices.
Charge deposition analysis of heavy-ion-induced single-event burnout in low-voltage power VDMOSFET
(2022-10-05) ALBERTON, S. G.; AGUIAR, V. A. P.; MEDINA, N. H.; ADDED, N.; MACCHIONE, E. L. A.; MENEGASSO, R.; CESARIO. G. J.; SANTOS, H. C.; SCARDUELLI, V. B.; ALCANTARA-NUNEZ, J. A.; Marcilei Aparecida Guazzelli; Roberto Santos; FLECHAS, D.
© 2022 Elsevier LtdThe heavy-ion-induced single-event burnout (SEB) risk in power MOSFETs (metal-oxide-semiconductor field-effect transistors) can be assessed in ground facilities, although it is costly and time-demanding. For this reason, there have been few experimental studies dedicated to investigate the relevant parameter related to the description of ion-induced SEB phenomenon. In this work the heavy-ion-induced SEB in a low-voltage power VDMOSFET (vertical double-diffused MOSFET) is studied using several ion-energy combinations. A self-consistent statistical analysis is carried out in order to elucidate the relationship between charge deposition and SEB triggering. Experimental data is compared to a predictive model from the literature for SEE (single-event effect) worst-case prediction in power MOSFETs, supporting for the first time its relevance to the worst-case prediction in the SEB mechanism.
Effective gamma-ray doses due to natural radiation from soil of southeastern Brazil
(2010) SILVEIRA, M. A. G.; Guazzelli, Marcilei A.; MEDINA, N. H.; MOREIRA, R. H.; AGUIAR, V. A. P.; BELLINI, B. S.
Effective gamma-ray doses due to natural radiation from soils of southeastern Brazil
(2010-12-05) Marcilei Aparecida Guazzelli; MEDINA, N. H.; MOREIRA, R. H.; BELLINI, B. S.; AGUIAR, V. A. P.
We have used gamma-ray spectrometry to study the distribution of natural radiation from soils of southeastern Brazil: Billings reservoir, São Bernardo do Campo Parks, Diadema Parks, Interlagos region, São Paulo, and soil from São Paulo and Rio de Janeiro beaches. In most of the regions studied we have found that the dose due the external exposure to gamma-rays, proceeding from natural terrestrial elements, are between the values 0.3 and 0.6 mSv/year, established by the United Nations Scientific Committee on the Effects of Atomic Radiation. © 2010 American Institute of Physics.
Electric field and temperature effects in irradiated MOSFETs
(2016-12-04) Marcilei Aparecida Guazzelli; SANTOS, R. B. B.; LEITE, F. G.; ARAUJO, N. E.; CIRNE, K. H.; MELO, M. A. A.; RALLO, A.; AGUIAR, V. A. P.; AGUIRRE, F.; MACCHIONE, E. L. A.; ADDED, N.; MEDINA, N.H.
© 2016 Author(s).Electronic devices exposed to ionizing radiation exhibit degradation on their electrical characteristics, which may compromise the functionality of the device. Understanding the physical phenomena responsible for radiation damage, which may be specific to a particular technology, it is of extreme importance to develop methods for testing and recovering the devices. The aim of this work is to check the influence of thermal annealing processes and electric field applied during irradiation of Metal Oxide Semiconductor Field Effect Transistors (MOSFET) in total ionizing dose experiments analyzing the changes in the electrical parameters in these devices.
Evaluating Soft Core RISC-V Processor in SRAM-Based FPGA under Radiation Effects
(2020-07-05) OLIVEIRA, A. B.; TAMBARA, L. A.; BENEVENUTI, F.; BENITES, L. A. C.; ADDED, N.; AGUIAR, V. A. P.; MEDINA, N. H.; Marcilei Aparecida Guazzelli; KASTENSMIDT, F. L.
© 1963-2012 IEEE.This article evaluates the RISC-V Rocket processor embedded in a Commercial Off-The-Shelf (COTS) SRAM-based field-programmable gate array (FPGA) under heavy-ions-induced faults and emulation fault injection. We also analyze the efficiency of using mitigation techniques based on hardware redundancy and scrubbing. Results demonstrated an improvement of $3\times $ in the cross section when scrubbing and coarse grain triple modular redundancy are used. The Rocket processor presented analogous sensitivity to radiation effects as the state-of-the-art soft processors. Due to the complexity of the system-on-chip, not only the Rocket core but also its peripherals should be protected with proper solutions. Such solutions should address the specific vulnerabilities of each component to improve the overall system reliability while maintaining the trade-off with performance.
Evaluating the Reliability of Different Voting Schemes for Fault Tolerant Approximate Systems
(2023-06-20) BALEN, T. R.; GONZALEZ, C. J.; OLIVEIRA, I. F. V.; DA ROSA JR. L. S.; SOARES, R. I.; SCHVITTZ, R. B.; ADDED, N.; MACCHIONE, E. L. A.; AGUIAR, V. A. P.; Marcilei Aparecida Guazzelli; MEDINA, N. H.; BUTZEN, P. F.
© 2023, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.This work presents a study on the reliability of voters for approximate fault tolerant systems in the context of single event effects and electromagnetic interference. A first case study analyses different topologies of single-bit majority voters for logic circuits employing fault injection by simulation. In these simulations, an analysis is first performed to identify the critical diffusion areas of the physical implementation according to the voter input vector. Additionally, as a second case study, practical heavy ion experiments on different architectures of software-based approximate voters for mixed-signal applications are also presented, and the cross section of each voter is evaluated. The system comprising the voters was irradiated in two distinct experiments with an 16O ion beam, producing an effective LET at the active region of 5.5 MeV/mg/cm 2 . As a complementary study, a conducted electromagnetic interference injection was also performed, considering two distinct voting schemes. Results of the case-studies allow identifying the most tolerant voter architectures (among the studied ones) for approximate computing applications under single event effects and electromagnetic interference.
Heavy ions induced single event upsets testing of the 28 nm Xilinx Zynq-7000 all programmable SoC
(2015-07-13) TAMBARA, L. A.; KASTENSMIDT, F. L.; MEDINA, N. H.; ADDED, N.; AGUIAR, V. A. P.; AGUIRRE, F.; MACCHIONE, E. L. A.; Marcilei Aparecida Guazzelli
© 2015 IEEE.The recent advance of silicon technology has allowed the integration of complex systems in a single chip. Nowadays, Field Programmable Gate Array (FPGA) devices are composed not only of the programmable fabric but also by hard-core processors, dedicated processing block interfaces to various peripherals, on-chip bus structures and analog blocks. Among the latest released devices of this type, this work focuses in the 28 nm Xilinx Zynq-7000 All Programmable SoC (APSoC). While not immune to the radiation environment in space, the Zynq-7000 seems to be very attractive for the aerospace sector due to its high computational power capability and low-power consumption. In this work, results from heavy ions testing for Zynq-7000 are presented. The experiments were performed in a Brazilian facility located at the University of São Paulo, Brazil.
Heavy-Ion-Induced Avalanche Multiplication in Low-Voltage Power VDMosfet
(2021-09-13) ALBERTON. S. G.; MEDINA, N. H.; ADDED, N.; AGUIAR, V. A. P.; Marcilei Aparecida Guazzelli; Roberto Santos
© 2021 IEEE.Lackner's theory for avalanche multiplication in semiconductor devices provides physical interpretation for the model parameters and obtaining them through experimental methods is necessary. In this work, the charge collection mechanisms of heavy-ion-induced avalanche multiplication in power MOSFETs are studied based on Lackner's impact ionization model. The heavy-ion-induced impact ionization coefficients were estimated by comparing collected charge values obtained from computational simulations and experimental measurements.
Isomeric state in the odd-odd 68Ga nucleus
(2022-01-05) ESCUDEIRO, R.; VASCONCELOS, C. E. C; ALLEGRO, P. R. P.; MEDINA, N. H.; TUFEN, D. L.; ADDED, N.; AGUIAR, V. A. P.; ALBERTON. S. G. P. N.; ALCANTARA-NUNEZ, J.; Marcilei Aparecida Guazzelli; MACCHIONE. E. L. A.; OLIVEIRA, J. R. B.; RIBAS, R. V.; SCARDUELLI, V. B.
© 2022 Institute of Physics Publishing. All rights reserved.The half life of the 7− isomeric state of the odd-odd 68Ga nucleus was measured using a particle-γ delayed coincidence technique. The 68Ga nuclei were produced using the fusion-evaporation reaction 55Mn(16O, 2pn)68Ga at 55 MeV incident beam energy. The beam was produced by the 8 MV Pelletron accelerator of the Nuclear Physics Open Laboratory of the University of São Paulo. The half life was measured using the Isomeric State Measurement System (SISMEI). The obtained value was 60.83(25) ns, compatible with previous measurements. The 68Ga excited states were well described with the Large Scale Shell Model using the JUN45 residual interaction.
Natural radioactivity and external hazard index in Brazilian sands
(2021-06-05) Marcilei Aparecida Guazzelli; MEDINA, N. H.; AGUIAR, V. A. P.
© 2021, Akadémiai Kiadó, Budapest, Hungary.The distribution of natural radiation from Brazilian beach sands was studied using gamma-ray spectrometry. While in most of the regions studied the dose due to external exposure to gamma-rays, proceeding from natural terrestrial elements, are within the values 0.3 and 1.0 mSv/year, some sand samples from Bahia, Rio de Janeiro and Sao Paulo states present higher radioactivity levels due to the presence of monazite and zircon, exceeding the world average value for external exposure due to naturally occurring radionuclides.
Neutron-Induced Radiation Effects in UMOS Transistor
(2022-01-05) ALBERTON. S. G.; BOAS, A. C. V.; MEDINA, N. H.; Marcilei Aparecida Guazzelli; AGUIAR, V. A. P.; ADDED, N.; FEDERICO, C. A.; GONZALEZ, O. L.; CAVALCANTE, T. C.; PEREIRA, E. C. F.; VAZ, R. G.
© 2022 Institute of Physics Publishing. All rights reserved.Ground level electronics and avionics systems may suffer from radiation effects induced by neutrons. Neutrons can induce radiation effects in electronic devices via fusion-evaporation nuclear reactions, but few studies have been reported for technologies such as UMOSFET. In this work, estimates and experimental studies on neutron-induced radiation effects via nuclear reactions in a Si-based UMOSFET are presented. Methods for probability estimates of neutron-induced Single-Event Effects (SEEs) in Si-based power transistors and neutron beam energy measurement is presented. The energy spectrum of a UMOSFET subject to fast neutron irradiation was then compared to that of a high charge collection efficiency silicon particle detector.
Reducing Soft Error Rate of SoCs Analog-to-Digital Interfaces with Design Diversity Redundancy
(2020-03-05) GONZALEZ, C. J.; ADDED, N.; MACCHIONE, E. L. A.; AGUIAR, V. A. P.; KASTENSMIDT, F. G. L.; PUCHNER, H. K.; Marcilei Aparecida Guazzelli; MEDINA, N. H.; BALEN, T. R.
© 1963-2012 IEEE.In this article, a commercial programmable system-on-chip (PSoC 5, from Cypress Semiconductor) is tested under heavy-ion irradiation with a focus on the analog-to-digital interface blocks of the system. For this purpose, a data acquisition system (DAS) was programmed into the device under test and protected with a design diversity redundancy technique. This technique implements different levels of diversity (architectural and temporal) by using two different architectures of converters (a Σ Δ converter and two successive approximation register (SAR) converters) operating with distinct sampling rates. The experiment was performed in a vacuum chamber, using a 16O ion beam with 36-MeV energy and sufficient penetration into the silicon to produce an effective linear energy transfer (LET) of 5.5 MeV/mg/cm2 at the active region. The average flux was approximately 350 particles/s/cm2 for 246 min. The individual susceptibility of each converter to single-event effects is evaluated, as well as the whole system cross section. Results show that the proposed technique is effective to mitigate errors originating at the converters since 100% of such errors were corrected by using the diversity redundancy technique. Results also show that the processing unit of the system is susceptible to hangs that can be mitigated using watchdog techniques.
Reliability analysis of gamma-and X-ray TID effects, on a commercial AlGaN/GaN based FET
(2021-01-05) BÔAS, A. C. V.; ALBERTON, S. G.; MEDINA, N. H.; AGUIAR, V. A. P.; MELO, M. A. A.; Roberto Santos; Renato Giacomini; CAVALCANTE, T. C.; VAZ, R. G.; JUNIOR E, C. F. P.; SEIXAS, L. E.; FINCO, S.; Marcilei Aparecida Guazzelli
© 2021, Brazilian Microelectronics Society. All rights reserved.—In this work, measurements were taken to investigate the robustness of a GaN HEMT to Total Ionizing Dose (TID) by a60gmmax values are dependable of the dose rate.DVTH values due to the TID, in this device are independent of the dose rate and the radiation source. However, the DCo Source. These results will be compared with a previous X-ray based work. Therefore, we will be, primarily, comparing both radiation sources. The robustness was investigated through IDxV curves and characteristic parameters of the irradiated device. The analysis included data acquired both from on-and off-state modes. The work concludes that the device is robust to TID, as it quickly recovered important parameters. Manly, the on-state mode, which presented a better performance compared to the off-mode. An analogous behavior was seen for X-ray. Finally, the.
Reliability Evaluation of Voters for Fault Tolerant Approximate Systems
(2021-10-27) BALEN, T. R.; GONZALEZ, C. J.; OLIVEIRA, I. F. V.; SCHVITTZ, R. B.; ADDED, N.; MACCHIONE, E. L. A.; AGUIAR, V. A. P.; Marcilei Aparecida Guazzelli; MEDINA, N. H.; BUTZEN, P. F.
This work presents a study on the reliability of voters for approximate fault tolerant systems in the context of single event effects. A first case study analyses different topologies of single-bit majority voters for logic circuits by means of fault injection by simulation. In these simulations a previous analysis is performed identifying the critical diffusion areas of the physical implementation according to the voter input vector. Additionally, as second case study, practical heavy ion experiments on different architectures of software-based approximate voters for mixed-signal applications are also presented, and the cross section of each voter is evaluated. The system comprising the voter was irradiated in two distinct experiments with an 16O ion beam, producing an effective $LET$ at the active region of 5.5 MeV/mg/cm2. Results of both case-studies allow identifying the most tolerant voter architectures (among the studied ones) for approximate computing applications under single event effects.
SAFIIRA: a heavy-ion multi-purpose irradiation facility in Brazil
(2020-05-05) AGUIAR, V. A. P.; MEDINA, N. H.; ADDED, N.; MACCHIONE, E. L. A.; ALBERTON, S. G.; LEITE, A. R.; AGUIRRE, F. R.; RIBAS, R. V.; PEREGO, C. C.; FAGUNDES, L. M.; TERASSI, J. C.; BRAGE, J. A. P.; SIMÕES, R. F.; MORAIS, O. B.; ALMEIDA , E. A.; JOAQUIM, P. M.; SOUZA, M. S. .; CECOTTE, F. M.; MARTINS, R.; DUARTE , J. G.; SCARDUELLI, V. B.; ALLEGRO, P. R. P.; ESCUDEIRO, R.; LEISTENSCHNEIDER, E.; OLIVEIRA, R. A. N.; SERVELO, W. A.; SILVA , M. T.; SARMENTO, V. E.; CARREIRA, C. A.; ABREU, J. C.; SILVA , S. C.; SANTOS, H. C.; RODRIGUES, C. L.; ASSIS, R. F.; SILVA, T. F.; TABACNIKS, M. H.; JOAQUIM, A. S.; MINAS, J. H. P.; KASHINSKY, D.; GUAZZELLI, Marcilei Aparecida; SEIXAS JR, L. E; FINCO, S.; BENEVENUTTI, F .
Este trabalho descreve as novas instalações de física nuclear aplicada da Universidade de São Paulo, principalmente para irradiação de dispositivos eletrônicos. É uma configuração composta por um quadrupolo dupleto para foco / desfoque de feixe mais espalhamento múltiplo através de folhas de ouro para produzir feixes de íons pesados de baixa intensidade, grande área e alta uniformidade de 1 H a 107 Ag. As intensidades do feixe podem ser facilmente ajustadas de 10 2 partículas cm 2 / s a centenas de nA para uma área tão grande quanto 2,0 cm 2 e uniformidade melhor que 90%. Sua câmara de irradiação possui estágio motorizado de alta precisão, e o sistema é controlado por um LabView TMambiente, permitindo a automação da medição. São apresentadas considerações de design e exemplos de uso.