Ultrastable and Quick Response UV Photodetector by High Crystalline Orientation Wurtzite/Zinc‐Blende GaN Superlattice

Abstract 1D gallium nitride (GaN) nanowires (NWs) can combine the intriguing properties of 1D materials with the wide bandgap nature of GaN materials. In this study, a type of high crystalline orientation wurtzite (WZ)/zinc‐blende (ZB) superlattice (SL) NWs is synthesized for the first time to the knowledge, which special structure can be also demonstrated by first‐principles calculation. The proposed GaN SL NWs UV PD demonstrates pronounced photoelectric performances working in a self‐powered mode, including a large responsivity (23.72 mA W ⁻¹ ), a high specific detectivity (4.4167 × 10 ¹¹ Jones), and a fast response speed (rise/decay time of 0.76/0.8 ms, significantly better than most of the gallium series NWs photodetectors reported so far). And the PD also exhibits excellent stability, enabling the photocurrent to remain largely consistent over a period of 18 months, which photoelectric current decay rate is less than 1%/year. These outstanding performance of WZ/ZB GaN SL NWs may be benefited from more stable structure and their diverse electronic channeling of GaN SL surface distributed gold quantum dots compared to that of pure WZ or ZB phase GaN. This research shows WZ/ZB GaN SL NWs' exceptional UV PD performance and new insights into their electronic structures for device applications.