High-voltage-resistant wafer-scale 4H-SiC ultraviolet photodetector with high uniformity enabled by electric field distribution modulation

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.