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Accelerated terrestrial neutron irradiations were performed on different commercial SiC power MOSFETs with planar, trench, and double-trench architectures. The results were used to calculate the failure cross sections and the failure-in-time (FIT) rates at sea level. Enhanced gate and drain leakage were observed in some devices which did not exhibit a destructive failure during the exposure. In particular, a different mechanism was observed for planar and trench gate MOSFETs, the first showing a partial gate rupture with a leakage path mostly between the drain and the gate, similar to what was previously observed with heavy ions, while the second exhibiting a complete gate rupture. The observed failure mechanisms and the postirradiation gate stress (PIGS) tests are discussed for different technologies. [ABSTRACT FROM AUTHOR]

Heavy-ion microbeams are employed for probing the radiation-sensitive regions in commercial silicon carbide (SiC) vertical double-diffused power (VD)-MOSFETs with micrometer accuracy. By scanning the beam spot over the die, a spatial periodicity was observed in the leakage current degradation, reflecting the striped structure of the power MOSFET investigated. Two different mechanisms were observed for degradation. At low drain bias (gate and source grounded), only the gate-oxide (at the JFET or neck region) is contributing in the ion-induced leakage current. For exposures at drain–source bias voltages higher than a specific threshold, additional higher drain leakage current is observed in the p-n junction region. This provides useful insights into the understanding of basic phenomena of single-event effects in SiC power devices. [ABSTRACT FROM AUTHOR]

The energy deposited by heavy-ion beams was measured using a passivated implanted planar silicon (PIPS) detector in different facilities. Ion beams at ultrahigh energy lead to the formation of a second, unexpected peak in the deposited energy spectrum at slightly higher energy, in addition to the expected primary peak. Monte Carlo simulations are used to shed light on the origin of this phenomenon and the underlying physical mechanisms. The importance of accounting for secondaries’ production in the packaging materials of the diode and the mechanisms at play are highlighted in the discussion of the results. [ABSTRACT FROM AUTHOR]

This paper describes a comparison between in-orbit single-event effects (SEE) rate measurement acquired by the CARMEN-3 experiment on-board the JASON-3 satellite (middle earth orbit, 1336 km, 66°) and an estimation using SEE rate calculation approaches from several facilities. A SRAM memory sensitive to single-event latchup (SEL) has been monitored in orbit, and the number of events per day was estimated using monoenergetic data coming from the Kernfysisch Versneller Instituut (protons) and Université Catholique de Louvain (heavy-ions) facilities as well as using mixed-field data coming from the Cern High energy AcceleRator Mixed field (CHARM) facility. A comparison of both estimations with respect to the in-flight measurement has been carried out. [ABSTRACT FROM AUTHOR]

High sensitivity of silicon-carbide (SiC) power MOSFETs has been observed under heavy-ion irradiation, leading to permanent increase of drain and gate leakage currents. The electrical postirradiation analysis confirmed the degradation of the gate oxide and the blocking capability of the devices. At low drain bias, the leakage path is formed between drain and gate, while at higher bias the heavy-ion-induced leakage path is mostly from drain to source. An electrical model is proposed to explain the current transport mechanism for heavy-ion degraded SiC power MOSFETs. [ABSTRACT FROM AUTHOR]

We investigated the potential of a multimode (50- $\mu \text{m}$ core diameter) nitrogen doped silica-based optical fiber for X-rays, protons, and $\gamma $ -rays radiation detection and dosimetry. X-rays results confirm that this N-doped fiber presents a strong radioluminescence (RL) around 550 nm when exposed to radiation. The RL observed from a few centimeter long samples linearly depend on the dose rate at least in the 1-mGy/s–50-Gy/s range. Low dose rate $\gamma $ -ray t ests demonstrate the radiation detection at dose rate as low as $40~\mu $ Gy/s with a 2-m-long fiber sample. This fiber is also associated with an optically stimulated luminescence (OSL) when exposed to a 1064-nm laser light postirradiation. This OSL signature provides shortly after the irradiation a precise estimation of the accumulated dose at least in the 1-Gy–10-kGy range. Under proton exposure, we benchmarked the performances of the N-doped fiber with the ones of a conventional Markus chamber used by the TRIUMF proton-therapy team. This comparison highlights the potential of the small-size N-doped fiber to partially overcome the known limitations of commercial fiber-based dosimeters for medical applications. The obtained results are very promising for the future design of more complex spatially resolved beam monitoring systems. [ABSTRACT FROM AUTHOR]

This paper summarizes the main results related to the single event upset and single event latch-up cross section measurements performed at CHARM in a location with a strong contribution from thermal and intermediate energy neutrons. We introduce a new experimental procedure to unfold the thermal and high-energy hadron contributions to the single event effect rate in the mixed-field environment and benchmark the result against those obtained in standard test facilities, highlighting the possible implications on the state-of-the-art component qualification. [ABSTRACT FROM AUTHOR]

A CubeSat payload (PL) was designed at CERN and at the University Space Center of Montpellier, for the measurement of radiation and its effects on electronics and single event latchup recording on SRAM devices. The PL and the data handling modules were tested at the CERN mixed-field facility, in a Low Earth Orbit representative environment. [ABSTRACT FROM AUTHOR]

In this paper, the single-event effects on a 28-nm static random access memory-based field-programmable gate array (FPGA) under CERN’s mixed-particle field are analyzed. The methodology followed for CERN electronics radiation hardness assurance and the particularities of testing an FPGA under a mixed-particle field are demonstrated. More specifically, the potential contribution of low-energy particles to the configuration memory (CRAM) and block memory (BRAM) bit upset sensitivity is investigated. By using a method of irradiating the device in different locations at CERN high-energy accelerator mixed field/facility with different particle energy spectra, it has been found that there is a significant impact of thermal neutrons, increasing the CRAM and BRAM cross section by a factor of $\times 3$. As a complement to this paper, an example application is also tested, in the context of future upgrades at the CERN accelerator complex. Results estimate that the application fails less than 10 times per year, leading to the conclusion that such devices may be used for low criticality applications along the accelerator complex. [ABSTRACT FROM AUTHOR]

A single event latchup (SEL) experiment based on commercial static random access memory (SRAM) memories has recently been proposed in the framework of the European Organization for Nuclear Research (CERN) Latchup Experiment and Student Satellite nanosatellite low Earth orbit (LEO) space mission. SEL characterization of three commercial SRAM memories has been carried out at the Paul Scherrer Institut (PSI) facility, using monoenergetic focused proton beams and different acquisition setups. The best target candidate was selected and a circuit for SEL detection has been proposed and tested at CERN, in the CERN High Energy AcceleRator Mixed-field facility (CHARM). Experimental results were carried out at test locations representative of the LEO environment, thus providing a full characterization of the SRAM cross sections, together with the analysis of the single-event effect and total ionizing dose of the latchup detection circuit in relation to the particle spectra expected during mission. The setups used for SEL monitoring are described, and details of the proposed circuit components and topology are presented. Experimental results obtained both at PSI and at CHARM facilities are discussed. [ABSTRACT FROM PUBLISHER]

Common-mode current generated by the pulse-width modulated (PWM) ac drive at low modulation index and higher switching frequency results in overheating of the precharge resistor of the silicon-controlled rectifier (SCR)-based rectifier. In this paper, two modifications are proposed for the operation of SCR-based rectifiers to significantly reduce the resistor overheating issue. The solution is cost and size effective when compared with alternative solutions. Experimental results are provided to show the reduction of common-mode current flow through the precharge resistor and the consequent reduction in its temperature. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM PUBLISHER]

A system to monitor the radiation levels is required in the Large Hadron Collider (LHC) and its injection lines in order to quantify the radiation effects on electronics. Thus, the RadMons were installed in critical areas where equipment is or will be placed. The first years of operation, successive test campaigns and new requirements, raised the need for a new design of the monitor. The architecture of the new RadMon, the radiation reliability and the design strategy adopted for the sensors, used for monitoring the mixed radiation field of the LHC accelerator, are described highlighting the achieved improvements in terms of radiation robustness and measurement accuracy of a device which is of interest for many other research institutes. [ABSTRACT FROM PUBLISHER]

An 8 Mbit 90-nm memory is proposed as a new high energy hadron fluence sensor. The obtained cross sections for protons (30 MeV up to 480 MeV) and thermal neutrons as well as their dependency on the TID together with the control circuitry is presented. Burst events were recorded during irradiation and an analysis on the causes has been performed proposing an algorithm to mitigate and correct the burst multiple events. Finally, the effects of the energy dependency on the measurements in the LHC mixed radiation field are discussed. [ABSTRACT FROM PUBLISHER]