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A single-event burnout (SEB) reliability and hardening method for 1.7-kV 4H-SiC power VDMOSFET under high liner energy transfer (LET) value range is proposed and researched by the 2-D numerical simulation. Compared with the conventional VDMOSFET with N-type multi-buffer layers, the hardened VDMOSFET not only ensures that the forward conduction capability does not deteriorate, but also reduces the peak electric field under breakdown voltage from 3.62 MV/cm to 2.98 MV/cm. The advantage of the hardened structure is providing a hole leakage path and increasing the contact area between the source metal and the N+ source, eliminating the effect of electron-hole pairs generated by heavy ion strike on the device, thus improving the SEB performance significantly. In addition, this fabricating technology is compatible with the current technological processes. This hardened structure provides a great potential in aerospace application. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) vertical-diffused metal oxide field transistor (VDMOSFET) is an important power device for aerospace application. However, it is sensitive to heavy particles radiation in space which can cause catastrophic single-event effects (SEEs). In this article, a method of SEE hardening at a high linear energy transfer (LET) value range is studied to the 1.2 kV-rated SiC VDMOSFET by the 2-D numerical simulator SILVACO TCAD. Simulation results illustrate that, compared with the VDMOSFET which only has four buffer (FB-VDMOSFET) layers, the improved MOSFET could increase the abilities of single-event burnout (SEB) and the single-event gate rupture (SEGR) of the device effectively. At the same time, the proposed MOSFET has the lower specific ON-resistance (${R}_{\text {on, sp}}$) at room temperature. As a result, the gate oxide of the FB-VDMOSFET has reached 7.5 MV/cm and the maximum temperature reached 2480 K at a voltage of 600 V and an LET value of 0.5 pC/ $\mu \text{m}$. However, the maximum temperature of the improved VDMOSFET is 2150 K when ${V}_{\mathrm {DS}}$ = 950 V. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

In this article, a novel snapback-free reverse-conducting insulated-gate bipolar transistor (RC-IGBT) with P+ pillars at the collector side (PPC) is proposed and investigated by TCAD simulations. This structure features the P+ pillar structure at the side of collector and exits a gap of N-buffers above N+ collector. The P+ pillars increase the distributed resistance below the buffer layer during turn-on transient, show bipolar mode, and eliminate the snapback phenomenon. Accordingly, the structure eliminates the snapback phenomenon with a smaller half-cell pitch of 10~μm, making that the device is more reliable and suitable for parallel connection. For the same forward voltage drop, the turn-off loss of the PPC structure is reduced by 34%. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

In this paper, a single-event burnout (SEB) hardening technique for Schottky diodes at a linear energy transfer (LET) value of 0.5 pC/μm (75.5 MeV/mg/cm2) is presented and investigated by 2-D numerical simulations. The simulation results show that, when compared with the conventional junction barrier Schottky (JBS) diode with multiple buffer layers, the proposed structure can significantly reduce the electric field at the metal/SiC interface with the help of the trench, thereby reducing the interface temperature. Moreover, the maximum global temperature of the proposed structure is also reduced. The maximum global temperature of the proposed structure is 1989 K and the temperature at the Schottky contact interface is 439 K for the bias voltage of 1000 V and LET value of 0.5 pC/μm (75.5 MeV/mg/cm2) which shows that the new structure has better SEB performance. In addition, the hardening method proposed in this paper can be applied at different breakdown voltages by adjusting the structural parameters of the device. • The SEB performance of SiC Schottky diode with the trench is investigated. • The SEB performance of the proposed SiC Schottky diode is significantly improved. • The improvement of SEB performance is mainly due to the introduction of the trench. [ABSTRACT FROM AUTHOR]