High-Performance Ultraviolet Photodetector Based on Single- Crystal Integrated Self-Supporting 4H-SiC Nanohole Arrays

Currently, the photodetectors (PDs) assembled by vertically aligned nanostructured arrays have attracted intensive interest owing to their unique virtues of low light reflectivity and rapid charge transport. However, in terms of the inherent limitations caused by numerous interfaces often existed within the assembled arrays, the photogenerated carriers cannot be effectively separated, thus weakening the performance of target PDs. Aiming at resolving this critical point, a high-performance ultraviolet (UV) PD with a single-crystal integrated self-supporting 4H-SiC nanohole arrays is constructed, which are prepared via the anode oxidation approach. As a result, the PD delivers an excellent performance with a high switching ratio (similar to 250), remarkable detectivity (6 x 1010 Jones), fast response (0.5 s/0.88 s), and excellent stability under 375 nm light illumination with a bias voltage of 5 V. Moreover, it has a high responsivity (824 mA/W), superior to those of most reported ones based on 4H-SiC. The overall high performance of the PDs could be mainly attributed to the synergistic effect of the SiC nanohole arrays' geometry, a whole single-crystal integrated self-supporting film without interfaces, established reliable Schottky contact, and incorporated N dopants.

Automated summary

In this study, a high-performance ultraviolet photodetector with single-crystal integrated self-supporting 4H-SiC nanohole arrays was constructed using the anode oxidation approach. The device exhibited high switching ratio, remarkable detectivity, fast response, and excellent stability under 375 nm light illumination. The synergistic effect of SiC nanohole arrays' geometry, a whole single-crystal integrated self-supporting film without interfaces, established reliable Schottky contact, and incorporated N dopants were identified as the key factors for the high performance of the photodetector.