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Experimental heavy-ion responses of 3-kV charge-balanced (CB) SiC power devices are compared with those of 3.3-kV planar SiC devices. The devices are similar, except the epitaxial region of the CB devices is heavily doped compared with the planar devices. The higher doping in the epitaxial region results in loweron-resistance, but typically leads to a lower threshold drain voltage at which single-event burnout (SEB) occurs. The experimental results demonstrate, however, that the CB devices have a similar SEB threshold to the planar devices due to the improved electric field distribution.

Random telegraph noise (RTN) measurements are performed on as-processed, programmed, erased, and irradiated 80 nm vertical charge-trapping nand memory transistors. Variations in current with time of up to ±20% are observed during the RTN testing interval. The RTN of these devices is relatively unaffected by irradiation of devices to 500 krad(SiO2). Root-mean-square (rms) magnitudes of measured RTN exceed predictions of number-fluctuation models (NFMs) by up to six-times. This result demonstrates that fluctuations in carrier scattering rates caused by motion and/or reconfiguration of traps at grain boundaries likely lead to a significant fraction of the low-frequency noise and/or RTN in poly-crystalline Si channel, charge-trapping memory devices. The magnitudes of these fluctuations may present significant challenges to the resolution of highly scaled 3-D memory devices.

In this work, a thorough assessment of the robustness of complementary channel HfO2 ferroelectric FET (FeFET) against total ionizing dose (TID) radiation is conducted, with the goal of determining its suitability for use as high-performance and energy-efficient embedded nonvolatile memory (eNVM) for space applications. We demonstrate that: i) ferroelectric HfO2 thin film is robust against X-ray and proton irradiation; ii) FeFET exhibits a polarization state dependent radiation sensitivity where the high- ${V} {_{\text {TH}}}$ (HVT) state sees noticeable negative ${V} {_{\text {TH}}}$ shift and low- ${V} {_{\text {TH}}}$ (LVT) is immune to irradiation, irrespective of the channel type; iii) the state dependence is ascribed to the depolarization field in the HVT, which points toward the channel and facilitates the transport and trapping of radiation-generated holes close to the channel. In the future, radiation hardening techniques need to be considered.

The importance of including secondary particles in particle environments for single event effects (SEE) simulations is examined by comparing total error rates with and without secondary alpha particles as a result of target fragmentation. Previous experimental single-event tests have demonstrated importance of short-range, high-LET secondary particles, produced by target fragmentation near to device. However, current error rate prediction workflows, based on tools such as CREME96 and SPENVIS, do not account for these secondary particles from target fragmentation. Reevaluating those practices shows that the impact of secondary alpha particles on total error rates is negligible for the environments, devices, and aluminum shielding explored. To compare the broader issue of nuclear reactions in overlaying materials, energy deposition simulations were done in MRED, which indicate that the composition and sequence of overlying materials need to be considered with regard to secondary particle production.

Single-event burnout (SEB) and single-event leakage current (SELC) behavior of 1200 and 3300 V silicon carbide (SiC) power devices are analyzed based on heavy-ion irradiation tests. Both SEB and SELC degradation thresholds are improved in the 3300 V devices by at least 300 V compared to the 1200 V devices. Additionally, it was demonstrated that the measured SEB threshold is a strong function of the device bias and irradiation history and that bias and irradiation steps at intermediate voltages between the charge collection region and SEB region can result in parametric failure from accumulated leakage current rather than catastrophic failure by burnout.

The properties of defects in n-p-n Si bipolar junction transistors (BJTs) caused by 17-MeV Si ions are investigated via current–voltage, low-frequency (LF) noise, and deep level transient spectroscopy (DLTS) measurements. Four prominent radiation-induced defects in the base–collector junction of these transistors are identified via DLTS. At least two defect levels are observed in temperature-dependent LF 1/f noise measurements, one that is similar to a prominent defect in DLTS and another that is not. Defect microstructures are discussed. Our results show that DLTS and 1/f noise measurements can provide complementary information about defects in linear bipolar devices.

A re-evaluation of experimental results within the context of first-principles calculations strongly suggests that interface traps can contribute significantly to low-frequency (1/ $f$ ) noise in irradiated MOS devices. Hydrogen-induced trap activation and passivation are likely origins of the observed fluctuations. Measured and calculated activation energies for hydrogen drift, diffusion, and dissociation are consistent with energetics of 1/ $f$ noise. The dominant noise source is determined by densities of relevant defect precursors, hydrogen concentrations, device processing, and history. When present, hydrogen-induced interface-trap activation and passivation adds to noise due to border traps. These results should help assess and assure the performance and reliability of analog integrated circuits in high radiation environments.

Total-ionizing-dose (TID) effects are evaluated in top-gated IGZO thin-film transistors (TFTs) irradiated with different gate biases. Negative-bias irradiation leads to worst case degradation of TID response, primarily due to enhanced charge trapping in the SiO2 insulator that underlies the IGZO channel and serves as an oxygen-penetration layer during device processing. TID response comparisons with back-gated devices indicate that hydrogen also plays an important role in the observed degradation of top-gated devices. The source of this hydrogen is most likely SiN oxygen blocking layers. Comparisons with other display and alternative-channel MOS technologies illustrate that further optimization should enable the use of IGZO in future space applications.