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Metal halide perovskites (MHPs) are low-temperature processable hybrid semiconductor materials with exceptional performances that are revolutionizing the field of optoelectronic devices. Despite their great potential, commercial deployment is hindered by MHPs lack of stability and durability, mainly attributed to ion migration and chemical interactions with the electrodes. To address these issues, 2D layered MHPs are investigated as possible device interlayers or active material substitutes. Here, the 2D perovskite (PEA)2PbBr4 is considered that is recently discussed as promising candidate for X-ray direct detection. While the increased resilience of (PEA)2PbBr4 radiation detectors has already been reported, the physical mechanisms responsible for such improvement compared to 3D perovskites are not still fully understood. To unravel the charge transport process in (PEA)2PbBr4 crystals thought to underly the device better performance, an investigation technique is adapted previously used on highly resistive inorganic semiconductors, called photo induced current transient spectroscopy (PICTS). It is demonstrated that PICTS can reliably detect three trap states (T1, T2, and T3), and that their evolution upon X-ray exposure can explain (PEA)2PbBr4 superior radiation tolerance and reduced aging effects. Overall, the results provide essential insights into the electrical characteristics of 2D perovskites and their potential application as reliable direct X-ray detectors.

Metal halide perovskites (MHPs) are low‐temperature processable hybrid semiconductor materials with exceptional performances that are revolutionizing the field of optoelectronic devices. Despite their great potential, commercial deployment is hindered by MHPs lack of stability and durability, mainly attributed to ion migration and chemical interactions with the electrodes. To address these issues, 2D layered MHPs are investigated as possible device interlayers or active material substitutes. Here, the 2D perovskite (PEA)2PbBr4 is considered that is recently discussed as promising candidate for X‐ray direct detection. While the increased resilience of (PEA)2PbBr4 radiation detectors has already been reported, the physical mechanisms responsible for such improvement compared to 3D perovskites are not still fully understood. To unravel the charge transport process in (PEA)2PbBr4 crystals thought to underly the device better performance, an investigation technique is adapted previously used on highly resistive inorganic semiconductors, called photo induced current transient spectroscopy (PICTS). It is demonstrated that PICTS can reliably detect three trap states (T1, T2, and T3), and that their evolution upon X‐ray exposure can explain (PEA)2PbBr4 superior radiation tolerance and reduced aging effects. Overall, the results provide essential insights into the electrical characteristics of 2D perovskites and their potential application as reliable direct X‐ray detectors. [ABSTRACT FROM AUTHOR]

The utilization of device for the space explorations, the active material of the device must show resilience toward cosmos radiation. In this work, the radiation hardness of ZnGa2O4‐based deep ultra‐violet (DUV) photodetectors (PDs) is examined using γ‐ray irradiation. Responsivity of the photodetector at zero bias is found to improve from 0.98 to 1.94 mA W−1, the dark current increased from 0.11 to 5.6 pA, while photo‐to‐dark current ratio (PDCR) increased the from 3.2 × 103 to 3.1 × 104 and the photocurrent decay time improved from 220 to 190 ms. The high‐resolution X‐ray photoelectron spectra (HR‐XPS) of O 1s core level peak is deconvoluted into two main peaks namely, O(I) and O(II), where the lattice oxygen of ZnGa2O4 is identified by the O(I) peak, while its surface oxygen defect is represented by O(II). A clear increment is observed in the percentage of oxygen defect peak, O(II), from 6.82 to 53.19% after 200 kGy. Also, the device remains undeteriorated after 200 kGy irradiation, indicating it to be a radiation‐hard device. These characteristics allow ZnGa2O4 DUV PDs to function effectively in cosmic radiation environments with the capability to operate on zero‐bias, regardless of the γ‐radiation. [ABSTRACT FROM AUTHOR]

Abstract This study investigates the impact of proton irradiation on perovskite devices fabricated fully through vacuum deposition. Exposure to irradiation induces changes in both electrical and optical properties. The analysis reveals that the main factors influencing the observed performance changes in solar cells are a significant reduction in shunt resistance and a minor increase in series resistance, with minimal alterations in recombination dynamics. Remarkably, the devices maintain promising photodetector characteristics both before and after proton irradiation, particularly in a self-powered mode without a reverse bias. These findings provide valuable insights into the resilience of vacuum-deposited perovskite devices against ionizing radiation, highlighting their potential for applications in radiation-prone environments, such as the nuclear industry or space exploration.

Nano-satellites, which are following the CubeSat standard have established for demanding industrial and scientific applications with critical requirements on reliability and radiation tolerance. The employment of commercial off-the-shelf components enables a state-of-the-art performance but requires extensive testing to avoid and mitigate malefunctions due to the space environment. The CubeSat mission CLIMB is representative for future missions with a complex payload, a high power budget and a harsh radiation exposure. For this reason, a comprehensive irradiation study of its on-board-computer was done. The total ionizing dose damage of 50 krad was evaluated at a 60 Co source. As a consequence of this test, specific components were exchanged before performing single event effect studies at the synchrotron accelerator MedAustron. A board-level test revealed that the majority of effects concern the central micro controller wherefore was followed by a component-level test. Those irradiation tests make use of a pencil beam to map the device under test, which provides additional information to localize effects - by the timestamp - at the expense of an increased irradiation time compared to a homogeneous exposure. In this paper, we summarize the major findings of the test campaign and mitigation means and present a procedure for single event effect studies at medical accelerators. [ABSTRACT FROM AUTHOR]

This paper investigates the performance of vacuum gate dielectric doping-free carbon nanotube/nanoribbon field-effect transistors (VGD-DL CNT/GNRFETs) via computational analysis employing a quantum simulation approach. The methodology integrates the self-consistent solution of the Poisson solver with the mode space non-equilibrium Green's function (NEGF) in the ballistic limit. Adopting the vacuum gate dielectric (VGD) paradigm ensures radiation-hardened functionality while avoiding radiation-induced trapped charge mechanisms, while the doping-free paradigm facilitates fabrication flexibility by avoiding the realization of a sharp doping gradient in the nanoscale regime. Electrostatic doping of the nanodevices is achieved via source and drain doping gates. The simulations encompass MOSFET and tunnel FET (TFET) modes. The numerical investigation comprehensively examines potential distribution, transfer characteristics, subthreshold swing, leakage current, on-state current, current ratio, and scaling capability. Results demonstrate the robustness of vacuum nanodevices for high-performance, radiation-hardened switching applications. Furthermore, a proposal for extrinsic enhancement via doping gate voltage adjustment to optimize band diagrams and improve switching performance at ultra-scaled regimes is successfully presented. These findings underscore the potential of vacuum gate dielectric carbon-based nanotransistors for ultrascaled, high-performance, energy-efficient, and radiation-immune nanoelectronics. [ABSTRACT FROM AUTHOR]

We propose an IGZO thin‐film transistor (TFT) with a multi‐layered gate dielectric for X‐ray flat‐panel detectors (FPDs). By minimizing X‐ray effects on the gate insulator and threshold‐voltage shift in the IGZO layer, we achieve high radiation hardness. These TFTs in FPD are ideal for medical imaging and nondestructive inspection. [ABSTRACT FROM AUTHOR]

The 3D trench silicon pixel sensors developed by the TimeSPOT collaboration have demonstrated exceptional performance, even after exposure to extreme radiation fluences up to 1⋅1017 1 MeV neq/cm2. This study assesses the radiation tolerance of these sensors using minimum ionizing particles during a beam test campaign. The results indicate that while radiation damage reduces charge collection efficiency and overall detection efficiency, these losses can be mitigated to levels comparable to non-irradiated sensors by increasing the reverse bias voltage. Charge multiplication was observed and characterised for the first time in 3D trench sensors, revealing a distinct operating regime post-irradiation achievable at bias voltages close to 300 V. Additionally, the timing performance of irradiated sensors remains comparable to their non-irradiated counterparts, underscoring their resilience to radiation damage. Currently, 3D trench silicon detectors are among the fastest and most radiation-hard pixel sensors available for vertex detectors in high-energy physics colliders. These findings highlight the potential of these sensors for new 4D tracking systems of future experiments at the Future Circular Hadron Collider (FCC-hh), advancing the capabilities of radiation-hard sensor technology.

3D trench silicon pixel sensors, recently developed by the TimeSPOT collaboration, have shown excellent performance in terms of spatial resolution, timing precision and detection efficiency. The combination of these three features make them one of the best candidate for inner tracking detectors operating in high luminosity hadron colliders experiments. This article presents systematic characterisations of these devices made with minimum ionising particles on irradiated sensors with neutrons up to 2.5 · 1016 1 MeV neq cm-2. The results show that 3D trench pixels have extremely high resistance to radiation. The measured time resolution and the detection efficiency of irradiated sensors match those of non-irradiated ones if a slightly higher bias voltage, few tens of Volts, is applied to the pixels. As of today, 3D trench pixels are the only sensors capable of achieving 10 ps time resolution after being irradiated at extremely high fluences, extending by far the capabilities of future tracking systems of HEP experiments operating under extreme conditions. [ABSTRACT FROM AUTHOR]

Copyright of e & i Elektrotechnik und Informationstechnik is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of e & i Elektrotechnik und Informationstechnik is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Deep space exploration, nuclear industry and high energy physics raise higher requirements for the radiation hardness of integrated circuits. However, the existing radiation hardening technologies, such as radiation hardness by design based on bulk silicon technology or silicon-on insulator (SOI) process, are difficult to ensure that the electronics in spacecrafts and nuclear facilities function well in extreme space and nuclear radiation environments. In response to the lack of clear technical paths for the development of ultra-high radiation-hardened chip, a new type of highly radiation-hardened technique was introduced in this paper, named configurable SOI (CSOI). This technology innovatively employs twice bonding and cutting method to fabricate ultra-high radiation hardened 200 mm wafers with embedded configurable silicon layers. The 0-18 μm CSOI complementary metal oxide semiconductor (CMOS) process was successfully developed, which opens up a new route to achieve radiation hardness through in-situ radiation compensation. After the fabrication of CSOI devices, the configuration layer voltage can be tuned flexibly to compensate for the performance degradation due to total ionizing dose (TID) effect and simultaneously suppress the parasitic transistor effect triggered by single event effects (SEE). This helps to improve the radiation hardness of the CSOI transistors. Technology computer aided design (TCAD) simulations validate the tuning mechanism of configurable layer that a negative bias does good to the hardness of both TID and SEE in N-type MOSFET. Based on the CSOI process platform, a design methodology for integrated circuits was developed through assessing the impact of tuning granularity (down to transistor level) and range (from -20 V to 5 V) of configurable layer on the performance and radiation tolerance of static random-access memory (SRAM) cell. Then, the optimized tuning strategy of configurable layer was determined, and a CSOI 4kb SRAM was designed and fabricated with high radiation tolerance. The TID irradiation of the CSOI 4kb SRAM chip was performed at the 60Co gamma irradiation source of Peking University and the SEE experiment was carried out at the Space Environment Simulation and Research Infrastructure (SESRI) in Harbin Institute of Technology. Radiation experiments confirm that the CSOI SRAM achieves up to a level of 6 Mrad(Si) for TID hardness and the threshold of single event upset is greater than 118 (MeV·cm2)/mg, which reaches world-class levels. It is expected to be applied in extreme fields such as deep space exploration and nuclear emergency.

In space applications, electronics must function while being strongly radiated. In this work, the radiation hardness property of the planar two-terminal nanoscale air channel device (NACD), which is a device of vacuum electronics, was demonstrated. Specifically, the total ionizing dose (TID) effect and single-event effects (SEEs) on the NACD were investigated. X-ray and pulse laser were utilized as the sources of TID radiation and SEE radiation, respectively. No significant degradation was observed after 1 Mrad-(Si) X-ray radiation, and no single-event transient phenomenon was detected at the pulse laser energy up to 5 nJ. Additionally, the physical mechanism of radiation hardness in the NACD was illustrated by theoretical analysis and finite element simulation. Taken together, the proposed work shows that the radiation hardness property of the NACD may have a prospect in deep space and nuclear energy applications. [ABSTRACT FROM AUTHOR]

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

3D trench silicon pixel sensors, recently developed by the TimeSPOT collaboration, have shown excellent performance in terms of spatial resolution, timing precision and detection efficiency. The combination of these three features make them one of the best candidate for inner tracking detectors operating in high luminosity hadron colliders experiments. This article presents systematic characterisations of these devices made with minimum ionising particles on irradiated sensors with neutrons up to 2.5 ⋅ 1016 1 MeV neq cm−2. The results show that 3D trench pixels have extremely high resistance to radiation. The measured time resolution and the detection efficiency of irradiated sensors match those of non-irradiated ones if a slightly higher bias voltage, few tens of Volts, is applied to the pixels. As of today, 3D trench pixels are the only sensors capable of achieving 10 ps time resolution after being irradiated at extremely high fluences, extending by far the capabilities of future tracking systems of HEP experiments operating under extreme conditions.

This paper investigates the performance of vacuum gate dielectric doping-free carbon nanotube/nanoribbon field-effect transistors (VGD-DL CNT/GNRFETs) via computational analysis employing a quantum simulation approach. The methodology integrates the self-consistent solution of the Poisson solver with the mode space non-equilibrium Green’s function (NEGF) in the ballistic limit. Adopting the vacuum gate dielectric (VGD) paradigm ensures radiation-hardened functionality while avoiding radiation-induced trapped charge mechanisms, while the doping-free paradigm facilitates fabrication flexibility by avoiding the realization of a sharp doping gradient in the nanoscale regime. Electrostatic doping of the nanodevices is achieved via source and drain doping gates. The simulations encompass MOSFET and tunnel FET (TFET) modes. The numerical investigation comprehensively examines potential distribution, transfer characteristics, subthreshold swing, leakage current, on-state current, current ratio, and scaling capability. Results demonstrate the robustness of vacuum nanodevices for high-performance, radiation-hardened switching applications. Furthermore, a proposal for extrinsic enhancement via doping gate voltage adjustment to optimize band diagrams and improve switching performance at ultra-scaled regimes is successfully presented. These findings underscore the potential of vacuum gate dielectric carbon-based nanotransistors for ultrascaled, high-performance, energy-efficient, and radiation-immune nanoelectronics.

High Entropy Alloys (HEAs) are prospective materials for nuclear fusion reactors and were irradiated in this study at a broad range of energetic ion fluences. Different ion masses (Cu and Au ions) and energies (3 and 5 MeV) were selected to investigate dpa (displacement per atom) development, radiation defect accumulation based on prevailing collision processes (Au ions) and ionization processes (Cu ions) in various HEAs. The studied HEAs differ in terms of elemental composition, internal morphology (grain structure) and other modifiers. Dpa values of 1 to ∼66 were achieved at Cu and Au ion fluences from 4 × 1014 to 1.3 × 1016 ions.cm−2 at room temperature, which generated varying levels of lattice damage. Theoretical simulations were performed to estimate the energy stopping and dpa depth distribution using SRIM code and compared with Au-concentration depth profiles determined by Rutherford backscattering spectrometry for Au-ions with 3 MeV ion energy. The prevailing energy losses of ions via ionization processes for Cu-5 MeV ions were found to increase the damage through lattice strain and probable lattice distortion, although the main defect introduction is expected to occur via collisions during nuclear stopping. Structural modification and defect accumulation were investigated by positron annihilation spectroscopy (PAS), which revealed a broader damaged layer with defects, where HEA-Nb (NbCrFeMnNi) exhibited the least damage accumulation from chosen alloys with no strong relation to the Au-5 MeV ion implantation fluence, whereas strong defect accumulation was recorded in the Au-ion implanted Eurofer97 used for comparison and HEA-Co (CoCrFeMnNi). PAS analysis also allowed defect sizes to be determined as an additional structural characteristic. The observed trends were also confirmed by thermal property analysis, with a worsening of thermal effusivity recorded after the irradiation in HEA-Co and Eurofer97. The worsening of the thermal properties was confirmed by the layer thickness, where the layer identified by PAS was found to be broader than the SRIM theoretical predictions. Nanoindentation measurements confirmed less pronounced radiation hardening of HEA-Nb relative to that observed in HEA-Co and Eurofer97. Transmission Electron Microscopy (TEM) analysis revealed layer thicknesses in reasonable agreement with the dpa depth profiles. The thermal effusivity decreased in the surface-irradiated layer in all investigated samples, the least influenced material was HEA-Nb.

Recent technology development in space mission design has raised a demand for space solar cells with a higher level of radiation tolerance as compared with state‐of‐the‐art, commercially available products. Therefore, new material systems are being investigated. Recently, we highlighted the superior radiation tolerance of GaInAsP solar cells to 1 MeV electron irradiation as compared with standard GaAs solar cells. A high InP fraction within this semiconductor compound was found to foster the regeneration rate of electron‐induced defects when the solar cells were annealed at 60°C under AM0 illumination, which are typical space‐operating conditions. In light of considering this material system in future radiation‐hard designs, the degradation of GaInAsP solar cells subjected to proton irradiation also needs to be investigated. Here, we report on the degradation and regeneration of GaInAsP solar cells lattice‐matched to InP substrates after 1 MeV proton irradiation. A detailed description of the radiation damage is achieved by solar cell numerical modeling combined with deep‐level transient spectroscopy analysis. The irradiation‐induced defects are quantified, and their evolution during annealing is monitored. The results are compared with the degradation data of similar solar cells obtained after 1 MeV electron irradiation. A slower regeneration rate of the proton‐induced defects is found in comparison with the electron‐induced defects. This difference is ultimately attributed to a different topology of the radiation damage caused by proton irradiation. [ABSTRACT FROM AUTHOR]

Brushless DC (BLDC) motors are widely used in payloads of scientific space missions. To work with this type of motor it’s required to develop a complex control system considering basic technical requirements as well as the demands to reliability linked with the space application of the system. The basic technical requirements and the demands for the reliability of the system were formulated in the article. The block commutation algorithm was selected for the system since it’s simple and it doesn’t require using a high-performance processor and precision rotor position sensors. Based on the selected algorithm and the requirements structural scheme of the control system with redundancy features was designed. Further, schematics for output stages of the system were considered. They allowed connecting one set of motors and Hall sensors to both the main and the redundant control system. To test the structural and schematic solutions a prototype board was developed. The prototype was successfully tested and the solutions were verified.

The radiation resistance to gamma irradiation of various dose levels (0.5, 2, 10 kGy) of a subterahertz radiation source from a heterodyne on a Gunn diode and a GaAs/AlAs semiconductor superlattice multiplier was estimated. A measuring chamber for studying the radiation resistance of Gunn diodes has been developed and manufactured. The dependence of the output power on the frequency of a sub-terahertz radiation source before and after irradiation was evaluated analytically. [ABSTRACT FROM AUTHOR]

While silicon has been a steadfast semiconductor material for the past 50 years, it is now facing competition from other materials, especially for detector design. In that respect, due to its high resistance to radiation damage, silicon carbide is one of the most promising materials. In this work, we discuss the radiation damage studies of a new, large area, p-n junction silicon carbide device developed by the SiCILIA collaboration. We have studied the general performances of several devices, as a function of fluence, irradiated in different experimental conditions with different beams. A standard p-n junction silicon detector was also irradiated for comparison. The new detectors manifest excellent performance in terms of stability of the main parameters, linearity, defect distribution, charge collection efficiency, energy resolution, leakage current, etc. Experimental results evidence a radiation resistance of SiC devices more than two order of magnitude higher than Si devices. The new construction technology applied to silicon carbide material has made it possible to create very robust devices with excellent performance. These devices will soon be available for all those scientific projects where a high resistance to radiation damage is required. [ABSTRACT FROM AUTHOR]

Due to the limits of the physical properties of conventional semiconductors against harsh environments, seeking a suitable material for next‐generation photoconversion devices with high‐temperature stability and strong radiation hardness has become a hot issue. Here, visible‐light photodetectors are fabricated on an N‐doped diamond. Their visible‐light detection via charge‐neutralized impurity levels including multi‐complex mid‐gap states induced crystal defects shows photosensitivity of at least four orders (104), the visible responsivity of 0.08 A W−1, and the detectivity of 3.9 × 1012 Jones. No significant deterioration of such figures of merit of photodetectors is observed even at an environmental temperature of 250 °C and after absorption to 10 MGy in the dose of white X‐ray. N‐doped diamond shows excellent potential to be applicable to visible‐light photodetectors for harsh‐environmental implementations, which conventional visible‐light photodetectors are not capable of so far. [ABSTRACT FROM AUTHOR]

A series of high-quality polystyrene-based plastic scintillators with fluorescent dyes such as b-PBD, p-TP and DPB as dopants have been synthesized by thermal bulk polymerization in an in-house developed muffle furnace to analyse the effect of dyes on their scintillation performance. The comparative studies revealed that b-PBD is the efficient fluorescent dye for the polystyrene-based plastic scintillator and shows better performance with high fluorescence intensity, short decay time of 3.3 and 6.2 ns under γ-ray and fast neutron excitation, significant radiation resistance and the light yield is found to be 50% of that of stilbene crystal. [ABSTRACT FROM AUTHOR]

We report findings on the Ion Beam Induced Charge (IBIC) characterization of a 4H-SiC Schottky barrier diode (SBD), in terms of the modification of the Charge Collection Efficiency (CCE) distribution induced by 20 MeV C ions irradiations with fluences ranging from 20 to 200 ions/μm2. The lateral IBIC microscopy with 4 MeV protons over the SBD cross section, carried out on the pristine diode evidenced the widening of the depletion layer extension as function of the applied bias and allowed the measurement of the minority carrier diffusion lengths. After the irradiation with C ions, lateral IBIC showed a significant modification of the CCE distribution, with a progressive shrinkage of the depletion layer as the fluence of the damaging C ions increases. A simple electrostatic model ruled out that the shrinkage is due to the implanted charge and ascribed the perturbation of the electrostatic landscape to radiation-induced defects with positive charge state. [ABSTRACT FROM AUTHOR]

In SRAM cells, as the size of transistors and the distance between transistors decrease rapidly, the critical charge of the sensitive node decreases, making SRAM cells more susceptible to soft errors. If radiation particles hit the sensitive nodes of a standard 6T SRAM cell, the data stored in the cell are flipped, resulting in a single event upset. Therefore, this paper proposes a low-power SRAM cell, called PP10T, for soft error recovery. To verify the performance of PP10T, the proposed cell is simulated by the 22 nm FDSOI process, and compared with the standard 6T cell and several 10T SRAM cells, such as Quatro-10T, PS10T, NS10T, and RHBD10T. The simulation results show that all of the sensitive nodes of PP10T can recover their data, even when S0 and S1 nodes flip at the same time. PP10T is also immune to read interference, because the change of the '0' storage node, directly accessed by the bit line during the read operation, does not affect other nodes. In addition, PP10T consumes very low-holding power due to the smaller leakage current of the circuit. [ABSTRACT FROM AUTHOR]

Single-event gate-rupture (SEGR) in the trench vertical double-diffused power MOSFET (VDMOS) occurs at a critical bias voltage during heavy-ion experiments. Fault analysis demonstrates that the hot spot is located at the termination of the VDMOS, and the gate oxide in the termination region has been damaged. The SEGR-hardened termination with multiple implantation regions is proposed and simulated using the Sentaurus TCAD. The multiple implantation regions are introduced, leading to an increase in the distance between the gate oxide and the hole accumulation region, as well as a decrease in the resistivity of the hole conductive path. This approach is effective in reducing the electric field of the gate oxide to below the calculated critical field, and results in a lower electric field than the conventional termination. [ABSTRACT FROM AUTHOR]

Compositionally complex materials have demonstrated extraordinary promise for structural robustness in extreme environments. Of these, the most commonly thought of are high entropy alloys, where chemical complexity grants uncommon combinations of hardness, ductility, and thermal resilience. In contrast to these metal–metal bonded systems, the addition of ionic and covalent bonding has led to the discovery of high entropy ceramics (HECs). These materials also possess outstanding structural, thermal, and chemical robustness but with a far greater variety of functional properties which enable access to continuously controllable magnetic, electronic, and optical phenomena. In this experimentally focused perspective, we outline the potential for HECs in functional applications under extreme environments, where intrinsic stability may provide a new path toward inherently hardened device design. Current works on high entropy carbides, actinide bearing ceramics, and high entropy oxides are reviewed in the areas of radiation, high temperature, and corrosion tolerance where the role of local disorder is shown to create pathways toward self-healing and structural robustness. In this context, new strategies for creating future electronic, magnetic, and optical devices to be operated in harsh environments are outlined.

Graphene sheets are a highly radiation-resistant material for prospective nuclear applications and nanoscale defect engineering. However, the precise mechanism of graphene radiation hardness has remained elusive. In this paper, we study the origin and nature of defects induced by gamma radiation in a graphene rolled-up plane. In order to reduce the environmental influence on graphene and reveal the small effects of gamma rays, we have synthesized a novel graphene-based nanocomposite material containing a bilayer of highly aligned carbon nanotube assemblies that have been decorated by organometallic compounds and suspended on nanoporous Al 2 O 3 membranes. The bilayer samples were irradiated by gamma rays from a 137 Cs source with a fluence rate of the order of 10 5 m − 2 s − 1 . The interaction between the samples and gamma quanta results in the appearance of three characteristic photon escape peaks in the radiation spectra. We explain the mechanism of interaction between the graphene sheets and gamma radiation using a pseudo-Majorana fermion graphene model, which is a quasi-relativistic N = 3 -flavor graphene model with a Majorana-like mass term. This model admits the existence of giant charge carrier currents that are sufficient to neutralize the impact of ionizing radiation. Experimental evidence is provided for the prediction that the 661.7-keV gamma quanta transfer enough energy to the electron subsystem of graphene to bring about the deconfinement of the bound pseudo-Majorana modes and involve C atoms in a vortical motion of the electron density flows in the graphene plane. We explain the radiation hardness of graphene by the topological non-triviality of the pseudo-Majorana fermion configurations comprising the graphene charge carriers. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC), thanks to its material properties similar to diamond and its industrial maturity close to silicon, represents an ideal candidate for several harsh-environment sensing applications, where sensors must withstand high particle irradiation and/or high operational temperatures. In this study, to explore the radiation tolerance of SiC sensors to multiple damaging processes, both at room and high temperature, we used the Ion Microprobe Chamber installed at the Ruđer Bošković Institute (Zagreb, Croatia), which made it possible to expose small areas within the same device to different ion beams, thus evaluating and comparing effects within a single device. The sensors tested, developed jointly by STLab and SenSiC, are PIN diodes with ultrathin free-standing membranes, realized by means of a recently developed doping-selective electrochemical etching. In this work, we report on the changes of the charge transport properties, specifically in terms of the charge collection efficiency (CCE), with respect to multiple localized proton irradiations, performed at both room temperature (RT) and 500 °C. [ABSTRACT FROM AUTHOR]

Fast and heavy inorganic scintillators with suitable radiation tolerance are required to face the challenges presented at future hadron colliders of high energy and intensity. Up to 5 GGy and 5 × 1018 neq/cm2 of one-MeV-equivalent neutron fluence is expected by the forward calorimeter at the Future Hadron Circular Collider. This paper reports the results of an investigation of proton- and neutron-induced radiation damage in various fast and heavy inorganic scintillators, such as LYSO:Ce crystals, LuAG:Ce ceramics, and BaF2 crystals. The experiments were carried out at the Blue Room with 800 MeV proton fluence up to 3.0 × 1015 p/cm2 and at the East Port with one MeV equivalent neutron fluence up to 9.2 × 1015 neq/cm2, respectively, at the Los Alamos Neutron Science Center. Experiments were also carried out at the CERN PS-IRRAD proton facility with 24 GeV proton fluence up to 8.2 × 1015 p/cm2. Research and development will continue to develop LuAG:Ce ceramics and BaF2:Y crystals with improved optical quality, F/T ratio, and radiation hardness. [ABSTRACT FROM AUTHOR]

Electromagnetic calorimetry in high-radiation environments, e.g., forward regions of lepton and hadron collider detectors, is quite challenging. Although total absorption crystal calorimeters have superior performance as electromagnetic calorimeters, the availability and the cost of the radiation-hard crystals are the limiting factors as radiation-tolerant implementations. Sampling calorimeters utilizing silicon sensors as the active media are also favorable in terms of performance but are challenged by high-radiation environments. In order to provide a solution for such implementations, we developed a radiation-hard, fast and cost-effective technique, secondary emission calorimetry, and tested prototype secondary emission sensors in test beams. In a secondary emission detector module, secondary emission electrons are generated from a cathode when charged hadron or electromagnetic shower particles penetrate the secondary emission sampling module placed between absorber materials. The generated secondary emission electrons are then multiplied in a similar way as the photoelectrons in photomultiplier tubes. Here, we report on the principles of secondary emission calorimetry and the results from the beam tests performed at Fermilab Test Beam Facility as well as the Monte Carlo simulations of projected, large-scale secondary emission electromagnetic calorimeters. [ABSTRACT FROM AUTHOR]

A new gain layer design, whose effective doping profile results from the difference between two overlapping implants of opposite dopant species (e.g. boron and phosphorus), is conceived to extend the operational life of Low-Gain Avalanche Diodes (LGADs) to fluences significantly above the present limit of 2. 5 ⋅ 1 0 15 1 MeV n eq / cm 2 . Both acceptor and donor atoms will experience doping removal due to irradiation, but their difference will remain fairly constant. The implementation of this ambitious goal necessitates a meticulous process of optimizing the two implants that constitute the gain layer of the Compensated LGADs. To this end, the Synopsys® Sentaurus TCAD toolkit, with the most up-to-date release of the Perugia radiation damage model, was employed, enabling a comprehensive investigation of these new sensors. This level of scrutiny is crucial for understanding the behaviour of the first Compensated LGAD production (2022 by FBK) and designing the subsequent batches of Compensated LGADs. [ABSTRACT FROM AUTHOR]

The upgrade program of the CMS experiment (CMS Collaboration, 2024) in view of the LHC High Luminosity phase (HL–LHC) includes a replacement of the silicon pixel tracker. This is necessary to guarantee the same tracking performance of the current detector under harsher operating conditions, including higher radiation fluences and hit rates. The first layer of the central (barrel) detector will be located at radial distance of 3 cm from the interaction point where the radiation fluence after 7 years of operation will be 1. 9 × 1 0 16 n eq / cm 2 . Following an extensive R&D program, comprising both laboratory and test beam measurements, 3D sensors will be employed in this layer due to their higher radiation tolerance and lower power consumption after irradiation. Test beam measurements after irradiation up to 1. 6 × 1 0 16 n eq / cm 2 showed a hit detection efficiency larger than 96% at normal incidence with less than 2% masked pixels, for applied bias voltages between 100 V and 130 V. [ABSTRACT FROM AUTHOR]

The Mu2e experiment at Fermilab will search for the neutrino-less coherent conversion of a muon into an electron in the field of a nucleus. Mu2e detectors comprise a straw tracker, an electromagnetic calorimeter and a veto for cosmic rays. The calorimeter employs 1348 Cesium Iodide crystals readout by silicon photo-multipliers and fast front-end, and digitization electronics. The digitization board is named DiRAC (Digitizer ReAdout Controller) and 140 cards are needed for the readout of the full calorimeter. The DiRACs are hosted in crates located on the external surface of calorimeter disks, inside the detector solenoid cryostat and must sustain very high radiation and magnetic field so it was necessary to fully qualify it. Several version of prototypes were validated for operation in a high-vacuum (10−4 Torr) and under a 1T magnetic field. An extensive radiation hardness qualification campaign, carried out with photons, 14 MeV neutron beams, and 200 MeV protons, certified the DiRAC design to sustain doses up to 12 krad, neutron fluences up to ∼ 1 0 11 1 MeV n e q / cm 2 , and very low occurrences of single-event effects. The qualification campaigns and quality assurance procedures will be reviewed. [ABSTRACT FROM AUTHOR]

Silicon photonics is emerging as a key technology for developing radiation-tolerant optical transceivers. In this work, we present the electro-optical characterization of two radiation-hardened shallow-etched Mach–Zehnder modulators with different doping configurations when exposed to 1.2 Grad(SiO 2) total ionizing dose. The trade-offs between radiation hardness and nominal performance metrics are highlighted to provide insights for optimizing SiPh devices for high-energy physics applications. [ABSTRACT FROM AUTHOR]

Many of our sensors were installed in the Large Hadron Collider (LHC), and they contributed to the discovery of the Higgs boson. The High Luminosity-LHC(HL-LHC) upgrade required significant improvements from the previous product specifications, such as one-digit-higher radiation hardness, reduction of dead area, flip chip bonding assembly, and so on. To overcome these challenges, various technologies were introduced during the sensor production process. As a result, we succeeded in developing a new Si sensor array (Si strip detector, Si pixel detector) for the HL-LHC. [ABSTRACT FROM AUTHOR]

LGAD devices from Teledyne e2v (a long-established commercial manufacturer of scientific imaging sensors) have been fully characterised before and after irradiation. Irradiations were performed with 27 MeV protons at the MC40 cyclotron in Birmingham to deliver a fluence from 5.6 × 1013 up to 8.3 × 1014 1 MeV n eq /cm2 to seven LGADs. Te2v LGADs were shown to exhibit the expected trends in breakdown voltage, gain and time resolution as seen in literature. Time resolution and gain performance before and after irradiation are reported here and compared with published results for other manufacturers of such devices. [ABSTRACT FROM AUTHOR]

A Cs 2 LiYCl 6 (CLYC) scintillation crystal is a promising candidate for fast neutron spectroscopy due to its dual mode gamma/neutron capability and good energy resolution. Despite promising features, CLYC's limited radiation tolerance and inability to separate alpha/proton particles using pulse shape discrimination (PSD) method restrict its applicability in fast neutron spectroscopy. The significant cross-sections for 35Cl(n,p)35S and 35Cl(n, α)32P reactions make 35Cl-containing crystals attractive candidates for fast neutron detection, prompting their development as a promising new solution. This study reports the growth of LaCl 3 crystals via the Bridgman technique, enabling further exploration of their scintillation and material properties for fast neutron detection applications. The effects of the proton irradiation on LaCl 3 crystals were investigated by irradiating them with a 100 MeV proton beam at the Korea Multi-purpose Accelerator Complex. The study quantified radiation damage by comparing the pre- and post-irradiation scintillation properties and PSD of the LaCl 3 crystals. The results of the measurements demonstrate that LaCl 3 crystals are promising candidates for applications in fast neutron identification, spectroscopy, and space mission, maintaining performance even under high-radiation environments. • Good alpha/proton separation capability of undoped LaCl 3 crystals. • We successfully grew undoped LaCl 3 crystals up to a size of 38 Φ mm x 25 mm. • Scintillation properties of the crystals showed good agreement with published values. • Direct unfolding method was achieved for fast neutron measurements. • Radiation hardness of LaCl 3 crystals was confirmed. [ABSTRACT FROM AUTHOR]

In this study, we investigated the radiation hardness of phosphate glasses doped with terbium (Tb) ions, having the composition 56 P 2 O 5 : 30 Na 2 CO 3 : 5 Al 2 O 3 : 8 Gd 2 O 3 : 1 Tb 4 O 7 , under proton and X-ray beam excitation. These glasses were synthesized using the melt and quench method. The dose distribution inside the volume of these samples was studied, and the absolute absorbed dose was calculated. The scintillation and optical properties, such as photoluminescence, transmission, absorption, etc., were studied and compared before and after exposure to irradiation. Under both types of irradiation, we observed two major emission peaks corresponding to the transitions 5 D 3 → 7 F 5 (at 480 – 510 nm, in the blue region) and 5 D 4 → 7 F 6 (at 535 – 565 nm, in the green region). The dominant green emission is attributed to the presence of Tb 3 + dopants. Notably, after X-ray irradiation, we observed a change in the sample's color, accompanied by a decrease in the intensity of all peaks. This suggests a potential limitation in the radiation hardness of Tb-doped phosphate glass. Similarly we checked the luminous intensity with 100 MeV proton beam. Furthermore, we conducted thermal annealing process to explore the possibility of radiation damage recovery and found out that sample does recover, its intensity recovered and its color change back to transparent from yellowish color. Our results highlight characteristics of Tb-doped phosphate glasses, which make them valuable for diverse applications such as radiation detection, dosimetry, radiography, biomedical imaging, and related fields. • Tb-doped phosphate glasses were prepared using the melt and quench method. • The sample was irradiated with X-rays and a 100 MeV proton beam. • At an absorbed dose of 90 Gy from X-rays, the sample changed to a yellowish color. • X-ray-damaged sample exhibited lower transmission compared to fresh sample. • Annealing restored X-ray-damaged sample to levels comparable with fresh samples. [ABSTRACT FROM AUTHOR]

This paper reviews recent progress in diamond radiation detectors. Diamond is an ultra-wide gap (5.5 eV) semiconducting material which has several ideal properties for radiation detectors, such as solar blindness, high temperature operation, and fast response. Furthermore, diamond has near tissue-equivalence due to its low atomic number (Z = 6) and chemical stability due to its strong covalent bonds. Because of these features, diamond has long been used as a radiation detector in the fields of nuclear engineering, nuclear fusion, high energy physics and medical therapy. Until the 1990s, most of the research was conducted using selected high purity natural diamonds. Since the 2000s, the detector characteristics of synthetic diamond detectors have been greatly improved by achieving high purity diamond by microwave plasma enhanced chemical vapor deposition (CVD). Single-crystal CVD diamonds present best characteristics for spectroscopy in diamond radiation detectors. For applications requiring large sensitive areas, polycrystalline CVD diamond is mostly used. Heteroepitaxial diamond detectors are a promising alternative to increase the area of spectroscopic diamond radiation detectors. For applications in extreme environments, high radiation flux which leads to polarization effects is a crucial issue. Even with diamond, which has excellent radiation hardness, degradation of detector characteristics due to irradiation is inevitable. Detectors designed with small carrier travel distances, such as membrane diamond detectors and three-dimensional diamond radiation detectors, are effective ways to mitigate the degradation.

We present a study on the radiation tolerance and timing properties of 3D diamond detectors fabricated by laser engineering on synthetic Chemical Vapor Deposited (CVD) plates. We evaluated the radiation hardness of the sensors using Charge Collection Efficiency (CCE) measurements after neutron fluences up to 10 16 n/cm 2 (1 MeV equivalent.) The radiation tolerance is significantly higher when moving from standard planar architecture to 3D architecture and increases with the increasing density of the columnar electrodes. Also, the maximum applicable bias voltage before electric breakdown increases significantly after high fluence irradiation, possibly due to the passivation of defects. The experimental analysis allowed us to predict the performance of the devices at higher fluence levels, well in the range of 10 16 n/cm 2 . We summarize the recent results on the time resolution measurements of our test sensors after optimization of the laser fabrication process and outline future activity in developing pixel tracking systems for high luminosity particle physics experiments. [ABSTRACT FROM AUTHOR]

Dynamic RON is a key parameter in terms of device reliability and the efficiency of power-switching converters. In this study, commercial off-the-shelf GaN-on-Si power high-electron-mobility transistors (HEMTs) were irradiated using different regimes of accumulative gamma rays with a 60Co source of photon energy (1.33 MeV), while a base temperature of 53 °C and 133 °C during the irradiation test was applied. This test campaign had the objective of investigating how the combination of gamma irradiation and temperature affects dynamic on-resistance (RON) behaviour. The results indicated that gate voltage bias stress affected the degradation of dynamic on-resistance when irradiation was applied, and that temperature was an accelerating factor in dynamic on-resistance degradation. Finally, we obtained a partial reduction in dynamic RON when a total ionising dose of around 140 krad(SiO2) was applied and the base temperature during the irradiation test was not high. [ABSTRACT FROM AUTHOR]

The theoretical basis of a hypothetical spherical electrode detector was investigated in our previous work. It was found that the proposed detector has very good electrical characteristics, such as greatly reduced full depletion voltage, small capacitance and ultra-fast collection time. However, due to the limitations of current technology, spherical electrode detectors cannot be made. Therefore, in order to use existing CMOS technology to realize the fabrication of the detector, a hemispherical electrode detector is proposed. In this work, 3D modeling and simulation including potential and electric field distribution and hole concentration distribution are carried out using the TCAD simulation tools. In addition, the electrical characteristics, such as I-V, C-V, induced current and charge collection efficiency (CCE) with different radiation fluences, are studied to predict the radiation hardness property of the device. Furthermore, a customized manufacturing method is proposed and simulated with the TCAD-SPROCESS simulation tool. The key is to reasonably set the aspect ratio of the deep trench in the multi-step repetitive process and optimize parameters such as the angle, energy, and dose of ion implantation to realize the connection of the heavily doped region of the near-hemispherical electrode. Finally, the electrical characteristics of the process simulation are compared with the device simulation results to verify its feasibility. [ABSTRACT FROM AUTHOR]