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We present experimental evidence of electron-induced upsets in a reference European Space Agency (ESA) single event upset (SEU) monitor, induced by a 200-MeV electron beam at the Very energetic Electronic facility for Space Planetary Exploration in harsh Radiation environments facility at CERN. Comparison of experimental cross sections and simulated cross sections is shown and the differences are analyzed. Possible secondary contributions to the upset rate by neutrons, flash effects, and cumulative dose effects are discussed, showing that electronuclear reactions are the expected SEU mechanism. The ESA Jupiter Icy Moons Explorer mission, to be launched in 2022, presents a challenging radiation environment due to the intense high-energy electron flux in the trapped radiation belts. Insight is given to the possible contribution of electrons to the overall upset rates in the Jovian radiation environment. Relative contributions of both typical electron and proton spectra created when the environmental spectra are transported through a typical spacecraft shielding are shown and the different mission phases are discussed.

International audience; This paper presents heavy-ion and proton radiation test results of a 90 nm COTS SRAM with stacked structure. Radiation tests were made using high penetration heavy-ion cocktails at the HIF (Belgium) and at RADEF (Finland) as well as low energy protons at RADEF. The heavy-ion SEU cross-section showed an unusual profile with a peak at the lowest LET (heavy-ion with the highest penetration range). The discrepancy is due to the fact that the SRAM is constituted of two vertically stacked dice. The impact of proton testing on the response of both stacked dice is presented. The results are discussed and the SEU cross-sections of the upper and lower layers are compared. The impact of the stacked structure on the proton SEE rate is investigated.

A methodology for power MOSFET radiation hardness assurance is proposed. It is based on the statistical analysis of destructive events, such as gate oxide rupture. Examples of failure rate calculations are performed.

The performance of a large area 4500times1966 pixel CCD was measured after alpha particle irradiation at -135degC. Trap concentrations (as measured by deferred charge and first pixel response) were a factor ~1.3 higher than after annealing to room temperature or after room temperature irradiation for most trapping defects and for some defects (with emission time ~13 ms) the factor was ~2. Hence it seems that room temperature irradiation cannot be guaranteed to bound the response to displacement damage for applications that use CCDs at low temperatures. Results are also compared with those obtained with room temperature proton irradiations

This paper reports on the radiation response of 90 nm CMOS transistors to a high fluence (3times1012 p/cm2) of ~60 MeV protons. A pronounced dependence on the gate bias VGS during the exposure has been noted for the n-channel devices: while no degradation of the input and output characteristics is found for VGS=0 V and a modest degradation for floating gate conditions, a catastrophic failure can be observed when a positive gate bias of 1.2 V is applied. This behavior is found for devices with a physical gate oxide thickness of 1.5 and 2 nm and appears to be more pronounced for larger area transistors. As will be shown, the breakdown site is connected with either the source-to-gate or drain-to-gate junction, whereby the latter leads to a complete loss of functionality of the transistors. However, some of the biased nMOSFETs survive the high-energy proton exposure without degradation. A model will be proposed, explaining the gate oxide breakdown in terms of pre-existing defect sites at the source or drain junctions which develop into breakdown sites under biased irradiation

A modeling framework for the prediction of the Martian radiation environment is presented. Features include input solar cycle modulated cosmic ray and solar particle event spectra, based both on CREME-96, the transport of this radiation in the Martian atmosphere and regolith, including creation of secondaries, using the Geant4 Monte Carlo toolkit. Details of the atmosphere are derived from the European Mars Climate Database with a dense topological grid and layering of the atmosphere. Seasonal and diurnal variations are considered. Surface topology is derived from the Mars Orbiter Laser Altimeter (MOLA) and geology is modeled. The outputs are full particle transport histories, maps of radiation fluxes, and doses. The model will be applied to future European Mars missions.

The main characteristics of the European Space Agency (ESA) Standard Radiation Environment Monitor (SREM) are outlined. First SREM results from the Project for On-Board Autonomy-I (PROBA-I) and INTEGRAL spacecraft are presented.