In this work, the after-pulse properties of 4H-SiC ultraviolet (UV) avalanche photodiodes (APDs) working in gated quenching mode are firstly characterized by using a double gate method. The after-pulse probability is determined as a function of delay time at various overbias voltages and temperatures. It is found that the after-pulse probability of 4H-SiC APDs would decrease at higher chip temperature, supporting the carrier trapping/releasing mechanism. Compared to state-of-the-art Geiger-mode Si APDs, the 4H-SiC APD exhibits considerably larger after-pulsing effect, which should be mainly caused by high density point defects within the SiC epilayer. The maximum signal repetition rate of the SiC APD in gated quenching operation mode is estimated, which is a key performance parameter for future UV laser radar and quantum communication applications.

中文翻译：

---

盖革模式 4H-SiC 雪崩光电二极管的后脉冲特性

在这项工作中，首先使用双栅极方法表征了在门控猝灭模式下工作的 4H-SiC 紫外 (UV) 雪崩光电二极管 (APD) 的后脉冲特性。后脉冲概率被确定为各种过偏电压和温度下延迟时间的函数。结果表明，4H-SiC APD 的后脉冲概率在芯片温度较高时会降低，支持载流子俘获/释放机制。与最先进的盖革模式 Si APD 相比，4H-SiC APD 表现出更大的后脉冲效应，这主要是由 SiC 外延层内的高密度点缺陷引起的。估算了 SiC APD 在门控淬火操作模式下的最大信号重复率，这是未来紫外激光雷达和量子通信应用的关键性能参数。