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In this brief, high-performance $8\times8$ arrays of 4H-SiC p-i-n ultraviolet (UV) photodiodes (PDs) with micro-hole structure are demonstrated. In order to improve the performance of the device, a periodic micro-hole structure (diameter = $4~\mu \text{m}$ ) was etched from the cap layer (p+ layer) to the i layer, which will elevate the effective absorption of UV light. The pixels in 4H-SiC p-i-n array show a low dark current of less than $2\times 10^{-{14}}$ A and a high yield of 98.4%. Devices with 4- $\mu \text{m}$ micro-hole reach a peak spectral responsivity of 0.159 A/W at 280 nm, which is 23.3% higher than that of the device without micro-hole. Moreover, the device has a faster response time of 2.2 ns and a high UV/visible rejection ratio of more than $10^{{4}}$ . The progress on the response performance is significant to the development of UV detection imaging.

Scintillators that convert ionization radiation photons to UV–visible photons have attracted extraordinary attention. Traditional scintillators are associated with a vacuum photomultiplier tube that faces strict constraints of fragility, magnetic fields, and operated voltage, or coupled to a silicon photomultiplier (SiPM) with optical silicone grease. Here, we report a high-performance radiation detector with an indirect photon-to-photon conversion radiation detection model based on perovskite single crystals (SCs), where perovskite SCs have been directly integrated into the window of SiPM by using the solution growth method at low temperature. Tunable X (γ)-ray excited light emission in the range of 414 to 600 nm is obtained with different concentrations of Br doping, which greatly matches the response wavelength of SiPM. Small Br-doped CH3NH3PbBr0.05Cl2.95SCs exhibit high transmittance and weak self-absorption, resulting in improved scintillation light emissions. Moreover, we have successfully collected a 137Cs source gamma-ray pulse height spectrum with the SiPM readout. The MAPbBr0.05Cl2.95scintillator exhibits a decay time of 0.14 ± 0.02 ns and a light yield of 18 000 photons/MeV with an energy resolution of 10.5 ± 0.4% at 662 keV. The results indicate that the CH3NH3PbBrxCl3–xperovskite SCs could enable the next generation of low-cost, fast, and fine-energy resolution scintillators.

An n-type charge layer was introduced into the 4H-SiC separated absorption and multiplication avalanche photodiode. The effect of the charge layer on the optoelectronic characteristics of the photodiode was modeled and studied to optimize the performance of the photodiode. According to the modeling results, 4H-SiC photodiodes were fabricated. A low breakdown voltage of 77.6 V and a significant gain of more than 105 were obtained. The peak responsivity for 270 nm illumination of the photodiode biased at [?]40 V was 83 mA W[?]1, corresponding to an external quantum efficiency over 38.2%. Both the simulated and experimental spectral responses are almost identical.