High-photosensitive ultraviolet photodetector based on an n-ZnO microwire/p-InGaN heterojunction

Researchers have focused on the achievement of high-performance self-biasing ultraviolet photodetectors because of their significance in scientific research and realistic applications. Herein, we proposed and constructed a high-photosensing ultraviolet photodetector, which is made of a single ZnO microwire doped by Ga (ZnO:Ga MW) and p-type InGaN layer. The carefully designed n-ZnO:Ga MW/p-InGaN heterostructure device can sensitively monitor a broadband wavelengths of light in the range of 300–500 nm. The photodetector can also operate in self-biased and reversely biased modes. Especially for the photoelectrical measurements operated in a self-driving manner, the device exhibits excellent photodetection performances, containing a maximum responsivity of 217 mA/W, a photodetectivity of 4.57 × 1012 Jones, a fast response speed (the rising/decaying times ∼175 μs/30 m) and a high Ion/Ioff ratio of about 6.5 × 104 upon 360 nm light illumination. The broadband and ultraviolet spectrum-selective photoresponse of the single ZnO:Ga wire heterojunction detector was principally derived from the resulting combination of ultraviolet-sensitive ZnO:Ga microstructures and ultraviolet–visible-sensitive capability of InGaN materials. Furthermore, the as-proposed n-ZnO:Ga/p-InGaN heterojunction could be functioned as an electrical power source with output voltage of about 1.18 V. This study may enable a potential significance in achieving high-performance self-driving ultraviolet photodetector, and other cost-effective and multifunctional optoelectronic devices.