Search Results (229)

This study experimentally compares the total ionizing dose (TID) responses of conventional and V-Gate regulated cascode transimpedance amplifier (RGC TIA)-based analog front ends (AFEs) fabricated in a 180 nm, 3.3 V CMOS process. Both AFEs were integrated on a single ASIC, and the V-Gate layout was applied to all NMOS devices in the hardened AFE. The powered circuits were driven with repetitive pulses and irradiated at 3.432 kGy/h to 13.73 kGy. At the final dose, pulse amplitude and slew rate decreased by 3.48% and 9.11% in the conventional AFE but by only 0.63% and 1.73% in the V-Gate AFE, corresponding to degradation reductions of approximately 82% and 81%, respectively. The IB_TP-derived bias current increased by 18.8% in the conventional AFE and 0.73% in the V-Gate AFE, while the input and output DC voltages remained stable. Leakage current sensitivity analysis identified the RGC TIA and bias generator as the main contributors to DC-level and pulse amplitude changes, whereas the Class-AB buffer and bias generator more strongly affected slew rate. A combined simulation reproduced the pulse amplitude reduction with a small DC shift. The results show that the V-Gate layout preserves the pulse response and bias stability of RGC TIA-based AFEs under TID irradiation. Full article

Benefiting from excellent high-frequency characteristics and superior radiation tolerance, InP is an indispensable material for next-generation high-speed communications, widely applied in optical communication, 6G radio frequency chips, AI optical interconnection, and aerospace radiation-hardened electronics. Although ion implantation greatly promotes the performance optimization of InP-based devices, it inevitably induces lattice displacement defects that degrade device reliability. Hence, quantitative evaluation of the threshold displacement energy (TDE) and dominant defect configurations in InP is essential. Our calculations reveal that the average threshold displacement energy is 18.20 eV for In atoms and 18.94 eV for P atoms. The E_d distributions for both In and P atoms predominantly lie below 30 eV and rarely exceed 40 eV. From 150 K to 900 K, In and P have a large mass difference and exhibit distinct temperature-dependent trends. The threshold displacement energy of In decreases with increasing temperature, whereas that of P rises as temperature increases. Based on the structural analysis of Frenkel pairs formed by displaced atoms, the dominant interstitial configurations are identified. These results provide detailed insights for damage evaluation and defect structure characterization in InP, benefiting ion implantation process optimization and radiation-hardening design of InP electronic devices. Full article

Erbium-doped fibers (EDFs) suffer from radiation-induced absorption (RIA) and radiation-induced gain variation (RIGV) under ionizing radiation, which limit their applications in space optical communication systems. To address this issue, a novel core–cladding Ce co-doped fiber is proposed, in which core Ce suppresses radiation-induced defect formation while cladding Ce reduces localized energy deposition in the fiber core. GEANT4 Monte Carlo simulations were performed to optimize the Ce-doping configuration, and three kinds of fiber samples, namely conventional erbium-doped fiber (EDF), core Ce co-doped EDF (CEDF1), and core–cladding Ce co-doped EDF (CEDF2), were fabricated for experimental validation. At a total dose of 1200 Gy, CEDF2 exhibits a 40.5% reduction in RIA and a 58.1% reduction in RIGV compared with the conventional EDF. The experimental results demonstrate that the proposed core–cladding Ce co-doped structure effectively enhances the radiation resistance of erbium-doped fibers and provides a practical design strategy for radiation-hardened active optical fibers. Full article

The fully depleted silicon on insulator (FDSOI) integrated circuit process has a buried oxygen layer in its structure, which provides many advantages to the FDSOI integrated circuit process, such as isolating the substrate from the conductive channel, reducing leakage current, and lowering the supply voltage. With the vigorous development of space artificial intelligence infrastructure in China and the United States, it is becoming increasingly important to study the single-event upset (SEU) of Static Random-Access Memory (SRAM) cells caused by particle radiation. In this paper, SRAM with different peripheral circuits is designed by domestically produced 22 nm FDSOI CMOS integrated circuit technology. Simulations are used to study the mechanism of single-event effects for SRAM, and single-particle radiation experiments of Kr are used to characterize SEU for SRAM. The results showed that the SRAM without Error Detection and Correction (EDAC) technology had 6486 cell upsets, with incidences of 2-cell upsets occurring 15 times, and no multi-cell flips occurred. For the SRAM using EDAC technology, there was no single-cell upset, 430 incidences of two-cell upsets and one incidence of multi-cell upsets. This provides strong support for fully utilizing EDAC technology to enhance the irradiation-hardening of digital integrated circuits. For metal oxide semiconductor field-effect transistors, the source and drain structures are completely symmetrical, and when in use, they are only connected at different potentials. Full article

Aging of asphalt pavements is a complex, multi-scale degradative process driven by the synergistic effects of various environmental stressors. Traditional laboratory-accelerated aging protocols often employ static parameters that fail to accurately replicate dynamic, region-specific climatic conditions. To bridge the gap between laboratory simulations and actual field performance, this study investigates the aging behaviors of base binder and SBS-modified binder under multi-factor coupled environmental conditions. Field observations were conducted across six distinct climatic regions in Gansu Province, alongside an indoor second-order orthogonal regression composite design that evaluated the interactive effects of temperature, ultraviolet (UV) radiation, humidity, and aging time. Rheological evaluations revealed that for the base binder, the synergistic coupling of UV radiation, elevated temperatures, and high humidity significantly accelerates oxidative hardening and embrittlement far beyond the impact of any single factor. Conversely, SBS-modified binder demonstrated a non-linear, U-shaped rheological response governed by a competitive mechanism between UV/thermal-induced polymer scission and moisture/time-driven matrix oxidation. Fourier Transform Infrared (FT-IR) spectroscopy corroborated these macroscopic findings at the molecular level, tracking the simultaneous evolution of carbonyl and sulfoxide indices alongside the degradation of the polybutadiene segments in the modified binder. Ultimately, a quadratic polynomial regression model was established to precisely correlate natural field aging with equivalent indoor accelerated aging times based on specific regional climatic data. Full article

Perovskite solar cells (PSCs) have emerged as a disruptive photovoltaic technology for aerospace and extreme environment applications, driven by their substantial power-to-weight ratio and mechanical flexibility. However, continuous operation under harsh conditions, characterized by the AM0 spectrum, deep vacuum, extreme thermal cycling, and ionizing radiation, exposes the fundamental thermodynamic instability of traditional organic–inorganic hybrid perovskites. This comprehensive review systematically synthesizes 131 recent studies to provide a holistic framework for designing ultrastable, radiation-hardened PSCs. We critically examine the underlying degradation mechanisms, including vacuum-induced volatile desorption, UV-triggered halide segregation, and thermomechanical fracture at buried interfaces. To overcome these critical barriers, we highlight advanced engineering strategies: the transition to all-inorganic CsPbX₃ and lead-free double/chalcogenide perovskites (e.g., Cs₂SnI₆, CaHfS₃), the implementation of dopant-free inorganic transport layers coupled with self-assembled monolayers (SAMs) for cascade band alignment, and the integration of polymeric scaffolds for fracture energy toughening. Furthermore, we emphasize the imperative shift toward solvent-free vacuum deposition techniques (ALD, PLD). A distinctive focus of this review is the integration of Artificial Intelligence; specifically, we evaluate Deep Learning architectures, such as Long Short-Term Memory (LSTM) networks, for predictive State of Health (SOH) monitoring, underscoring the vital transition from simulated to empirical datasets. Finally, coupled with Material Flow Cost Accounting (MFCA), this review outlines a strategic roadmap for the commercialization and deployment of autonomous, self-diagnosing photovoltaic platforms in next-generation satellite and deep-space missions. Full article

Spaceborne neural processing units (NPUs) increasingly support real-time deep-learning inference, but their dense multiply-accumulate arrays are vulnerable to radiation-induced soft errors. Conventional radiation-hardening methods improve reliability through hardware redundancy, but they incur substantial area, performance and compiler-mapping overheads. This paper proposes tile-resilient algorithm-based fault tolerance (TR-ABFT), a software-scheduled, detection-oriented scheme for quantized NPU inference. TR-ABFT generates checksum information at tile granularity and maps checking tasks onto the original processing element (PE) array without changing the hardware topology. To make ABFT compatible with INT8 datapaths, we design two checksum-coding strategies: checksum decomposition and modulo-239 checksum coding. The modulo-239 scheme removes structural missed detections for two-bit flips with bit-position spacings in (1, 31), while preserving compatibility with signed INT8 inputs. Evaluations on ResNet, YOLOv8, and RT-DETR show that, on a $16\times 16$ array, TR-ABFT introduces only 6.37% to 24.61% additional computational overhead. By converting spatial redundancy into schedulable temporal redundancy, TR-ABFT preserves systolic-array regularity and provides a low-overhead reliability-enhancement mechanism for space-grade neural-network accelerators. Full article

The increase in small satellites demands the integration of commercial components to reduce costs and development time. However, the lack of standardized system-level methodologies to mitigate radiation-induced degradation limits their adoption. Although majority-carrier technologies such as MOSFET transistors dominate space power electronics, modern commercial off-the-shelf BJT transistors present a robust and cost-effective alternative. This paper evaluates the viability of the new-generation commercial off-the-shelf BJT transistors in space radiation environments by analyzing their response to total ionizing dose (measured at the circuit level) and single-event effects (inferred from component-level data). A fault-tolerant design methodology is proposed based on the strict definition of the safe operating area: the collector-emitter voltage is limited to safe values to mitigate single-event burnout, and an overdrive margin, specifically a 5× worst-case factor, is applied to compensate for the parametric degradation of the current gain. These strategies are empirically validated through two circuits: a voltage clamp and a proportional base driver operating in the 5 W to 40 W range. Experimental tests on the voltage clamp demonstrate stable operation up to one hundred kilorads, exceeding the 50 krad mission requirement by 100%. This indirectly supports the proportional base driver through shared mitigation principles, which rely on base current over-dimensioning to compensate for TID degradation. In conclusion, by applying appropriate derating rules, commercial off-the-shelf BJT transistors constitute a viable and robust alternative for small satellite power systems, mitigating the need for expensive radiation-hardened components. Full article

The rapid expansion of artificial intelligence and cloud computing is straining terrestrial data center infrastructure, motivating exploration of space-based data centers (SBDCs) as a scalable and energy-efficient alternative. While orbital platforms offer unique advantages, including continuous solar energy, radiative cooling, and global coverage, their practical deployment is constrained by unresolved reliability challenges across the mission lifecycle. This study presents a lifecycle-oriented reliability and risk assessment for SBDCs spanning launch, orbital operation, maintenance, and end-of-life phases, using a structured systems-level analysis of failure modes and operational dependencies. This paper focuses on compute-centric SBDC architectures, treating storage solely as a supporting resource. We identify and classify space-environment-specific risks, including launch-induced mechanical stress, radiation-driven degradation, thermal extremes, and single points of failure in power and communication subsystems. By integrating engineering constraints with economic considerations, we develop a unified risk-chain framework that shows how reliability limitations propagate from component design to system cost and operational viability. The analysis reveals a critical trade-off: achieving terrestrial-grade reliability in orbit requires substantial redundancy and radiation hardening, increasing mass and cost and reducing economic feasibility, whereas lower-reliability designs introduce operational and financial risks that challenge sustainability. These findings establish reliability as the central determinant of SBDC viability, providing an applied foundation for fault-tolerant, modular, and lifecycle-aware design strategies essential for transitioning orbital cloud infrastructure from concept to scalable reality. Full article

Electrolytic-plasma hardening of steel components requires reliable non-contact temperature monitoring, but traditional pyrometry is complicated by the variable emissivity of steel and the intense radiation of the plasma envelope. This work presents an approach that repurposes a compact multispectral AS7341 sensor into a virtual temperature sensor based on physically grounded spectral feature engineering and regularized machine learning. The use of logarithmic ratios of the near-infrared channel (940 nm) to the visible channels suppresses the plasma contribution and linearizes Wien’s radiation law. On a controlled dataset of 20 cycles, this increases the Pearson correlation with the peak temperature from r = 0.498 (raw NIR channel) to r = 0.781 for the log(NIR/Clear) feature. Current is identified as a confounding variable; normalizing the NIR/Clear ratio by the cycle-averaged current (r = 0.761) ensures correct signal interpretation under varying process conditions. Two narrow channels–NIR (940 nm) and F8 (680 nm)–provide accuracy equivalent to the broadband Clear channel (r = 0.778 vs. 0.781), thus simplifying hardware implementation. Ridge regression using three weakly correlated features (log(NIR/Clear), cycle duration, and initial temperature) achieves a mean absolute error of 91.4 °C under leave-one-out cross-validation (LOOCV) and 85.5 °C on an independent current-group test (R² = 0.536). Independent verification by scanning electron microscopy and Vickers microhardness on 30KhGSA steel confirms reliable separation of the three thermal regimes: underheating (<800 °C, 280–320 HV), optimal quenching (800–900 °C, 620–680 HV, fine-needle martensite), and overheating (>900 °C, 540–590 HV). The proposed set of spectral features provides a physically justified basis for a low-cost industrial temperature sensor for electrolytic-plasma processing. Full article

This study presents a TCAD model of a SiGe HBT designed for high-speed data transfer, with a cutoff frequency of 246.5 GHz and a β-value up to 416.7. Comprehensive single-event transient (SET) irradiation simulations were performed by injecting charges at different junctions with various angles. The influence of SET on data transfer was further evaluated at circuit level by loading the SET model from TCAD simulation into a high-speed laser diode driver circuit. Hence, this work employed a collector dummy structure in the designed HBT to build radiation-hardened devices. Simulation results indicate significant mitigation of the single-event transient current, which could be reduced to 10%, compared with non-hardened devices. Full article

This paper presents a register-transfer-level (RTL) fault injection study of the LEON3 processor’s internal memory subsystem under single-event upsets (SEUs). The analysis targets four key components: the instruction cache (I-cache), data cache (D-cache), AHB bus control interface, and memory controller (MCTRL), all of which are unprotected in the standard LEON3 configuration. Using the NETFI+ fault injection framework, multi-cycle SEUs are injected into sequential elements across these blocks while executing a memory-intensive benchmark. The results show that the AHB interface is extremely fragile, with every fault causing execution failure. The memory controller, though architecturally invisible, frequently induces precise SPARC V8 traps such as window overflow and illegal instruction through indirect data-path corruption. The data cache is identified as the primary source of silent data corruption (SDC), while the instruction cache exhibits partial natural masking but remains susceptible to control-flow errors. These findings highlight the disproportionate impact of unprotected protocol and controller logic on system reliability and inform targeted hardening strategies for LEON3-based embedded systems in radiation-prone environments. Full article

This study investigates the irradiation response of two L1₂-strengthened HEAs, (Ni₂Co₂FeCr)₉₂Ti₄Al₄ (TiHEA) and (Ni₂Co₂FeCr)₉₂Nb₄Al₄ (NbHEA), subjected to 6.4 MeV Fe³⁺ irradiation at 500 °C up to 30 dpa. Transmission electron microscopy (TEM) and atom probe tomography (APT) consistently showed that the Ti-containing HEA maintains L1_2-ordered structure and compositional stability better than Nb-containing alloys under irradiation. This difference is attributed to the distinct solute–defect interactions. Ti imposes a weaker hindering effect on vacancy mobility, allowing vacancies to remain mobile and participate in thermal reordering processes that counteract ballistic mixing, whereas Nb acts as a strong vacancy trap, suppressing the diffusion required for structural recovery. Irradiation-induced dislocation loops in the two alloys further exhibited different characteristics. TiHEA showed larger loops at lower number density, and NbHEA exhibited a higher density of smaller loops, consistent with their respective stacking fault energies and loop mobility. Nanoindentation results indicated that TiHEA exhibited a slightly higher irradiation hardening rate (27%) than NbHEA (23%), likely associated with a stronger order-strengthening contribution, given the better preservation of precipitate order in TiHEA under irradiation. These findings show the critical role of solute addition in designing radiation-tolerant high-entropy alloys. Full article

The downscaling of VLSI technologies has exacerbated the susceptibility of integrated circuits (ICs) to radiation-induced Single-Event Transients (SETs). This work presents UPSET, a comprehensive and technology-independent EDA framework for probabilistic SET analysis using Static Timing Analysis (STA). Unlike traditional simulation-based methods that suffer from prohibitive runtimes, UPSET leverages graph-based propagation with advanced logical, electrical, and timing-window masking models to evaluate circuit sensitivity efficiently. Key contributions include a novel “Electrical Masking Window” (EMW) criterion that effectively filters non-full-rail pulses early in reconvergent logic and a TimeStamp-based propagation mode that accurately handles complex signal reconvergence with Boolean evaluation. The experimental results over some featured benchmarks demonstrate a speedup of more than 25,000× compared with SPICE while maintaining a tight 4.56% error bound in pulse width estimation. Moreover, experimental validation on 50 benchmarks across varying complexities showcases that EMW enhancement reduces the pessimism to circuit sensitivity by up to 25% on average, providing tighter upper bounds while maintaining scalability to million-gate designs. By integrating seamlessly with standard industrial formats (LEF, DEF, LIB, or SPEF), UPSET enables scalable, accurate soft SET sensitivity assessment for modern digital designs, establishing a robust foundation for automated radiation hardening flows. Full article