In this work, ultraviolet (UV) 4H-SiC avalanche photodiodes (APDs) with a diameter of 150 μm were fabricated and investigated. The impact of resistance on the performance of 4H-SiC APDs was analyzed both in linear and Geiger modes. The optical response time of the fabricated APD devices in linear mode was measured with various load resistances, whereas the single photon counting performance in Geiger mode was carried out based on the passive-quenching circuit with different quenching resistances. The results show that the response time and the single-photon counting performance are strongly dependent on the series resistances. The response time (i.e., rising time and falling time) in the linear mode increases almost linearly with the load resistance increasing. In the Geiger mode, the photon count rate (PCR) decreases with the increasing quenching resistance. However, at some reverse bias voltages, the ratio of single photon detection efficiency (SPDE) to dark count rate (DCR) is positively correlated to the quenching resistance. Therefore, in order to obtain the optimal performance of 4H-SiC APDs, the resistance in the circuit must be carefully adjusted for practical usage. The results in this work will be very useful and can provide a reference for researchers in the fields of 4H-SiC APD UV detectors.

中文翻译：

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电阻对紫外 4H-SiC 雪崩光电二极管性能的影响


在这项工作中，制造并研究了直径为 150 μm 的紫外 (UV) 4H-SiC 雪崩光电二极管 (APD)。在线性和盖革模式下分析了电阻对 4H-SiC APD 性能的影响。在不同的负载电阻下测量了所制作的APD器件在线性模式下的光学响应时间，而在盖革模式下的单光子计数性能则基于具有不同猝灭电阻的无源猝灭电路进行。结果表明，响应时间和单光子计数性能强烈依赖于串联电阻。线性模式下的响应时间（即上升时间和下降时间）几乎随着负载电阻的增加而线性增加。在盖革模式下，光子计数率（PCR）随着猝灭电阻的增加而降低。然而，在某些反向偏压下，单光子检测效率（SPDE）与暗计数率（DCR）的比率与猝灭电阻呈正相关。因此，为了获得4H-SiC APD的最佳性能，必须根据实际使用仔细调整电路中的电阻。这项工作的结果非常有用，可以为4H-SiC APD紫外探测器领域的研究人员提供参考。