Wide bandgap semiconductors are ideal materials for ultraviolet (UV) photodetectors due to their stable optoelectronic properties and high efficient UV light absorption. However, photodetectors based on pure wide bandgap semiconductors typically have large dark current that inhibit the devices from generating high UV photoresponse. Herein, a high-voltage-resistant wafer-scale 4H-SiC UV photodetector enabled by electric field distribution modulation is proposed. As the P+ region introduced by the ion implantation process affects the electric field distribution and suppresses the Schottky barrier lowering effect, the dark current of the device reaches pA-level, and remains nA-level at a bias voltage of 1 kV. Meanwhile, the device exhibits superior photoresponse, including a prominent responsivity of 105.7 A/W, a remarkable detectivity of 1.01 × 10¹⁴ Jones, an outstanding photoconductive gain of 477, and a high light on/off ratio of 1.84 × 10⁵. This device provides a reliable solution for high-performance UV photodetectors that require high-voltage-resistant in special areas, and the wafer-scale fabrication process makes it feasible for practical applications.

Wide-bandgap semiconductors have demonstrated considerable potential for fabricating solar-blind ultraviolet (SBUV) photodetectors, which are extensively used in both civilian and military applications. Despite this promise, the limited variety of semiconductors with suitable bandgaps hampers the advancement of high-performance SBUV detectors. In this study, we synthesized CdPS₃ transparent single crystals using the chemical vapor transport (CVT) method. Density functional theory (DFT) calculations suggest that the bandgap of CdPS₃ decreases as the material’s thickness increases, a finding corroborated by subsequent absorption spectra and photoelectric response measurements. The as-prepared CdPS₃ nanosheets were employed as channels in photodetectors, demonstrating outstanding photoelectric performance in the solar-blind ultraviolet range (at 254 and 275 nm) with high responsivity (0.3 A/W), high specific detectivity (5.5 × 10⁹ Jones), rapid response speed (2.6 ms/3.4 ms), and exceptionally low dark current (2 pA). It is noteworthy that these nanosheets exhibit almost no sensitivity to 365 nm and visible light irradiation, attributable to the direct carrier transition beyond the broad bandgap in CdPS₃. Furthermore, high-quality imaging was achieved under different gate voltages using 275 nm ultraviolet light, underscoring the potential of CdPS₃ as a new material for high-performance SBUV optoelectronic detection.

Topological insulators have important potential for applications in the field of nano/micro-optoelectronic devices. However, the large dark current seriously hinders the improvement of device performance. Alloying is an important means to control the physical properties of topological insulators. In this work, we have designed and prepared Bi_1.3In_0.7Se₃ crystals. The optoelectronic properties of the individual Bi_1.3In_0.7Se₃ nanowire-based photodetector are systematically investigated. The photodetector is very sensitive to broadband wavelength from solar-blind ultraviolet C (254 nm) to near-infrared (1,064 nm), showing superior optoelectrical properties with photoresponsivity of 241.3 A·W^–1 and detectivity of 1.18 × 10¹² Jones at 638 nm. Furthermore, the photodetector demonstrates ultrafast photoresponse characteristics with a photoresponse time of about 770 ns, which is 3 to 6 orders of magnitude lower than other compound semiconductors based on Bi or In reported so far. In addition, it also exhibits good polarization sensitivity in a broadband range from ultraviolet C (266 nm) to near-infrared (1,064 nm) and obtained the maximum dichroic ratio is 1.73 at 1,064 nm. Our results suggest that this platform creates new opportunities for the development of low-cost, high-sensitivity, high-speed, and broadband angle-sensitive photodetectors.