In this letter, high-performance 4H-SiC ultraviolet (UV) single-photon avalanche diodes (SPADs) with a large diameter of 300 μm were designed and fabricated. For the first time, the influence of an incident UV photon flux on the single-photon-counting performance of 4H-SiC SPADs is investigated. With the UV photon flux increasing from ~100 photons/s·μm2 to 2.3×104 photons/s·μm2, the ratio of photon count rate (PCR) to dark count rate (DCR) exhibits a non-monotonic variation while the single-photon detection efficiency (SPDE) is monotonically decreased. A maximum SPDE of 9.8% with a DCR of 10 Hz/μm2 is obtained for our large-area 4H-SiC SPAD with a photon flux of 209 photons/s·μm2 at the wavelength of 280 nm. In addition, the stability of our 4H-SiC SPAD is also preliminarily proved by the high-temperature storage test at 150 °C for more than 200 hours in N2 ambient, which indicates the potential capability of our 4H-SiC SPADs to operate in harsh environment for UV single-photon detection.

中文翻译：

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具有宽范围入射通量的 4H-SiC 雪崩光电二极管的单光子计数性能


在这封信中，设计并制造了大直径 300 μm 的高性能 4H-SiC 紫外 (UV) 单光子雪崩二极管 (SPAD)。首次研究了入射紫外光子通量对 4H-SiC SPAD 的单光子计数性能的影响。随着紫外光子通量从~100 photons/s·μm2增加到2.3×104 photons/s·μm2，光子计数率（PCR）与暗计数率（DCR）之比呈现出非单调变化，而单光子计数率则表现出非单调变化。光子探测效率（SPDE）单调递减。我们的大面积 4H-SiC SPAD 的最大 SPDE 为 9.8%，DCR 为 10 Hz/μm2，波长为 280 nm 时光子通量为 209 photons/s·μm2。此外，我们的4H-SiC SPAD的稳定性也通过N2环境中150°C超过200小时的高温存储测试得到了初步证明，这表明我们的4H-SiC SPAD具有在恶劣环境下运行的潜在能力。紫外单光子检测环境。