In this work, an improved 4H-SiC insulated gate bipolar transistor (IGBT), or CTH-IGBT, with a trench p-polySi/p-SiC heterojunction on the backside of the device is proposed to reduce the turn-off energy loss ( $E_{off}$ ) and turn-off time ( $T_{off}$ ). The electrical properties of the proposed and contrast structures are all simulated using the ATLAS simulation software to research the working mechanism of this improved structure. For the static performance, the specific ON-resistance ( $R_{on,sp}$ ) and the figure of merit ( ${\mathrm{ FOM}} = V_{BR}^{2}/ R_{on,sp}$ ) are not influenced much as compared to the traditional structure at the same breakdown voltage ( $V_{BR}$ ) of 12 kV. However, with a prominent electron current path formed by the heterojunction region of CTH-IGBT, a very available conduction path to discharge the electrons during turn-off process is proved in this article. The simulation results demonstrate that compared with the traditional structure, the turn-off energy loss of the CTH-IGBT is reduced by 76.4%, while the turn-off time is reduced by 85.0%.

中文翻译：

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具有沟槽异质结集电极的低关断损耗 4H-SiC 绝缘栅双极晶体管

在这项工作中，提出了一种改进的 4H-SiC 绝缘栅双极晶体管 (IGBT) 或 CTH-IGBT，在器件背面具有沟槽 p-polySi/p-SiC 异质结，以减少关断能量损失。 $E_{off}$ ) 和关闭时间 ( $T_{off}$ ）。提出的结构和对比结构的电性能均使用 ATLAS 仿真软件进行仿真，以研究这种改进结构的工作机制。对于静态性能，特定导通电阻 ( $R_{on,sp}$ ) 和品质因数 ( ${\mathrm{ FOM}} = V_{BR}^{2}/ R_{on,sp}$ ) 在相同击穿电压下与传统结构相比影响不大 ( $V_{BR}$ ) 的 12 kV。然而，由于CTH-IGBT的异质结区域形成了一个突出的电子电流路径，本文证明了一种非常可用的在关断过程中释放电子的传导路径。仿真结果表明，与传统结构相比，CTH-IGBT的关断能量损耗降低了76.4%，关断时间降低了85.0%。