Ruben Garcia Alia

SEU Measurements and Simulations in a Mixed Field Environment

Single Event Upset (SEU) measurements were performed using the European Space Agencys (ESA) Standard SEU Monitor in the H4 Irradiation mixed-field test area at CERN. The results, tightly correlated with the radiation environment, are compared with those obtained with the CERN Radiation Monitors (RadMons) as well as with the Monte Carlo simulation of the experimental setup using the FLUKA Monte Carlo transport code. In addition, the SEU cross section of the device for particles and energies not available in standard testing (such as charged pions or GeV-energy hadrons) are simulated and discussed, showing an increase of over a factor 2 for nucleons in the 200 MeV-3 GeV range. A monoenergetic SEU cross section measurement at 120 GeV is included in the analysis.

CHARM: A Mixed Field Facility at CERN for Radiation Tests in Ground, Atmospheric, Space and Accelerator Representative Environments

Depending on the application, electronic systems and devices can be subjected to different radiation environments. According to the type of radiation encountered during operation, electronic components are simultaneously vulnerable to cumulative and single event effects. In addition, inelastic interactions of highly energetic particles with high-Z materials generate highly ionizing products. This can lead to catastrophic failures and therefore can have a significant impact on the reliability of electronic devices. For this reason, it is necessary to test electronic devices/systems in representative environments. For this purpose, a mixed field radiation test facility called CHARM has been established at CERN. Its radiation environment is not only representative of particle accelerators, but also of atmospheric, ground level and space applications.

SEL Hardness Assurance in a Mixed Radiation Field

This paper explores the relationship between monoenergetic and mixed-field Single Event Latchup (SEL) cross sections, concluding that for components with a very strong energy dependence and highly-energetic environments, test results from monoenergetic or soft mixed-field spectra can significantly underestimate the operational failure rate. We introduce a semi-empirical approach that can be used to evaluate the SEL rate for such environments based on monoenergetic measurements and information or assumptions on the respective sensitive volume and materials surrounding it. We show that the presence of high-Z materials such as tungsten is particularly important in determining the hadron cross section energy dependence for components with relatively large LET thresholds.

Energy Dependence of Tungsten-Dominated SEL Cross Sections

The energy dependence of proton-induced Single Event Latchup (SEL) failures is investigated for different Static Random Access Memories (SRAMs) and an Analog-to-Digital Converter (ADC) through experimental measurements in the 30-230 MeV range. It is observed that for several of them, the measurements are not compatible with a saturation below the maximum energy tested. A Monte Carlo based model is proposed that explains the observed cross section increase through the presence of tungsten near the sensitive region and is used to extrapolate the SEL cross section to larger energies. The significant cross section increases expected by the model up to 3 GeV are quantified and discussed, potentially having a strong impact on the failure rate for energetic environments such as high-energy accelerators or the avionics contexts.

SEE Measurements and Simulations Using Mono-Energetic GeV-Energy Hadron Beams

Single Event Upset (SEU) measurements were performed on the ESA SEU Monitor using mono-energetic GeV-energy hadron beams available in the North Experimental Area at CERN. A 400 GeV proton beam in the H4IRRAD test area and a 120 GeV mixed pion and proton beam at the CERN-EU high Energy Reference Field facility (CERF) were used for this purpose. The resulting cross section values are presented and discussed as well as compared to the several hundred MeV case (typical for standard test facilities) from a physical interaction perspective with the intention of providing a more general understanding of the behavior. Moreover, the implications of the cross section dependence with energy above the several hundred MeV range are analyzed for different environments. In addition, analogous measurements are proposed for Single Event Latchup (SEL), motivated by discussed simulation results. Finally, a brief introduction of the future CHARM (CERN High-energy AcceleratoR Mixed facility) test installation is included.

SEL Cross Section Energy Dependence Impact on the High Energy Accelerator Failure Rate

We use a single event latchup (SEL) model calibrated to heavy ion (HI) and proton data below 230 MeV to extrapolate the proton cross section to larger energies and evaluate the impact of the potential cross section increase with energy on the SEL rate in different environments. We show that in the case of devices with a large LET onset for HI and a certain amount of tungsten near the sensitive volume (SV), the calculated failure rates for energetic environments based on monoenergetic test data can significantly underestimate the real value. In addition, we show through measurements using a 480 MeV beam and an inspection of the devices architecture that the model was successful in estimating the SEL cross section and tungsten volume per cell.

The Effect of Proton Energy on SEU Cross Section of a 16 Mbit TFT PMOS SRAM with DRAM Capacitors

Proton experimental data are analyzed for a 16-Mbit thin-film-transistor (TFT) PMOS static random access memory (SRAM) with DRAM capacitors. The presence of high-Z materials as tungsten causes an unusual increase of the single event upset (SEU) proton cross section for the energies above 100 MeV. Monte-Carlo simulations reproduce the experimentally measured cross sections up to 480 MeV and predict a further increase up to GeV energies. The implications of this increase are analyzed in the context of the LHC and other radiation environments where a significant fraction of the fluence lies above 100 MeV.

Monte Carlo Evaluation of Single Event Effects in a Deep-Submicron Bulk Technology: Comparison Between Atmospheric and Accelerator Environment

In this work, the expected SEE rate in a generic model of a state-of-the-art SRAM memory was studied as a function of the critical charge in different radiation environments. The FLUKA Monte Carlo code was used to evaluate the SEE mono-energetic cross section for different particles as well as the SEE rate in different mixed field environments through an energy deposition analysis. Mono-energetic cross sections for protons and both positively and negatively charged muons were evaluated in the 0.1–1000 MeV energy range. The SEE rate was calculated for different mixed radiation field environments such as the terrestrial environment, commercial flight altitude, LHC critical areas for electronics and CERN’s CHARM test facility. Results show that direct ionization from charged particles becomes predominant between 0.2-1.1 fC compared to indirect neutron energy deposition. Finally the CHARM facility was demonstrated to be able to reproduce with a good approximation both the atmospheric and accelerator environments, particularly with regard to avionics, ground level applications and LHC.

A Mixed Field Facility at CERN for Radiation Test: CHARM

A new mixed-field radiation test facility called CHARM is available at CERN since end of 2014. Its radiation environment is not only representative for accelerators, but also for atmospheric, ground level and space applications.

Sub-LET Threshold SEE cross section dependency with ion energy

This study focuses on the ion species and energy dependence of the heavy ion SEE cross section in the sub-LET threshold region through a set of experimental data. In addition, a Monte Carlo based model is introduced and applied, showing a good agreement with the data in the several hundred MeV/n range while evidencing large discrepancies with the measurements in the 10-30 MeV/n interval, notably for the Ne ion. Such discrepancies are carefully analyzed and discussed.