The leakage current degradation, single-event burnout (SEB), and single-event gate rupture (SEGR) behaviors induced by the heavy-ion irradiation in p-Channel and n-Channel power U-shaped metal–oxide–semiconductor field-effect transistors (UMOSFETs) are comparatively investigated in this article via experiments and simulations. The SEB and SEGR performances of a commercially available −100-V-rated p-Channel UMOSFET are tested under heavy-ion irradiation. The experimental results show that the sample devices can be prevented from the drain leakage current or gate leakage current degradation under the bias conditions of $V_{\mathrm {GS}} = -100$ V and $V_{\mathrm {GS}} = 0$ . However, a severe gate leakage current degradation can occur at $V_{\mathrm {DS}} = -100$ V when $V_{\mathrm {GS}} \ge 5$ V. In addition, the SEB and SEGR characteristics of a 100-V-rated n-Channel UMOSFET are obtained by simulations. The simulation results indicate that a p-Channel UMOSFET can achieve much better robustness against heavy ions compared with an n-Channel UMOSFET. Further, the leakage current degradation and failure mechanisms induced by heavy-ion irradiation are investigated via simulations. Finally, an effective method, which enlarges the width and depth of the source contact trench, is introduced to enhance the SEB tolerance of an n-Channel UMOSFET. The simulation result shows that the SEB threshold voltage can represent an increase of 23.1% with the hardening method.

In this article, the performance and triggering mechanism of the single-event burnout (SEB) of a 4H-SiC trench-gate (TG) MOSFET structure are evaluated by the 2-D numerical simulations. The novel N⁺ island buffer 4H-SiC TG MOSFET and the conventional TG 4H-SiC MOSFET are analyzed and compared to examine whether an N⁺ island region introduced in the second buffer can effectively reduce the impact ionization located at the N⁻ drift/N⁺ buffer junction and improve device tolerance to the SEB. The TCAD simulation results revealed that compared with the conventional structure, which is a simple double-buffer structure, the N⁺ island buffer-hardened structure changed the burnout threshold voltage, improving the SEB performance significantly. In addition, the results proved that the impact ionization played an important role in the SEB triggering mechanism, significantly affecting the SEB performance of the 4H-SiC TG MOSFET. The performance of the hardened N⁺ island buffer with a different dopant concentration of N-buffer 2 and a size of N⁺ island is discussed. The specific burnout threshold voltage at the optimal parameters of the proposed structure is 47% higher than that of the conventional structure.

This article presents the 2-D numerical simulation results of the heavy-ion-induced leakage current degradation and single-event burnout (SEB) in the rated 1.2-kV silicon-carbide (SiC) super-junction (SJ) vertical diffusion metal-oxide-semiconductor (VDMOS). The employed simulation physics models were validated by the heavy-ion irradiation experiments of the commercially rated 1.2-kV SiC common VDMOS (C-VDMOS), which indicated a severe degeneration threshold of 500 V. The SiC common SJ VDMOS (C-SJ VDMOS) was proven to be sensitive to high-energy heavy-ion and represents comparative SEB performance compared with the SiC C-VDMOS. The robustness of the SiC SJ VDMOS with different single buffer layer (SBL) designs against a heavy-ion was simulated. It is found that the maximum temperature in the source metal/SiC interface and bottom of the structure could be compromised by the thickness of the buffer layer. As a result, the SiC SJ VDMOS with an optimal SBL exhibited a severe degeneration threshold of 800 V, which was a 60% increase compared to the SiC C-SJ VDMOS.

This paper presents the 2-D numerical simulation results of single-event burnout (SEB) in 4H-SiC junction barrier Schottky (JBS) diode by low carrier lifetime control (LCLC) for the first time. We investigate the SEB performance based on an 1800-V JBS structure and find that the most sensitive ion's strike position is the middle of junction spacing because of the punchthrough of the electric field at anode contact. Then, the SEB hardening mechanism of LCLC is studied in this paper that the double-sided peak electric field can be effectively improved which results in a significantly decrease of maximal temperature. For the incident particle with different linear energy transfer values, we find that the SEB threshold voltage can be substantially enhanced when the carrier lifetime (τ) is under a certain value. In addition, the basic characteristics with LCLC are discussed that the forward and reversed characteristics are hardly affected.

This brief presents 2-D numerical simulation results of a single-event burnout (SEB) in a 4H-silicon carbide (SiC) junction termination extension (JTE) termination structure of a power metal-oxide-semiconductor field-effect transistor (MOSFET). Using the rated 1.5-kV JTE termination structure, the most sensitive ion's strike position to SEB is proved to be the edge of the P ⁺ /P ^- JTE region. Due to the severe punchthrough of the electric field, the source contact region is found to the most sensitive region to induce an SEB event. The SEB performance of the JTE termination structure with a single buffer layer or multilayer buffer is evaluated. The results show that the electric field distribution in four buffer layers (FBLs) is the most uniform to achieve the best SEB performance. Therefore, by adding an optimal FBL design to the termination region, the SEB threshold voltage can be increased to 1210 V instead of the common structure's 250 V. The SEB safe operating area of the power MOSFET with an optimal FBL can increase more than three times compared with the common one.

Since neutrons are electrically neutral, the methods used to detect neutrons generally rely on secondary charged particles, which are produced by the interaction of neutrons and neutron conversion materials (such as ⁶ LiF, ¹⁰ B). In this report, the SRIM code has been used to analyze the ionization properties of $\alpha $ particles and ³ H particles traveling through the Silicon Carbide (SiC) diode, and subsequently, the final Bragg ionization distribution has been obtained. Next, according to the obtained ionization distribution of secondary particles, the linear energy transfer (LET) distribution of the secondary particles is extraced accurately. Finally, based on the distribution of LET, Technology Computer Aided Design (TCAD) simulations are utilized to analyze the transient current pulses of thin-film-coated and trench-type SiC diodes. In addition, the effects of particle energy and applied reverse bias on the output pulse characteristics of SiC diodes are also explored. Essentially, this paper augments the understanding of output response from SiC neutron detectors, and for trench-type detectors, the order of output current pulse amplitude decreases significantly and has a long-tail. Therefore, the trench-type detectors not only need a more advanced fabrication process but also require the design of dedicated readout electronics.