The light-induced pyro-phototronic effect improving a ZnO/NiO/Si heterojunction photodetector for selectively detecting ultraviolet or visible illumination.

In this work, we fabricate a ZnO/NiO/Si heterojunction photodetector, which successfully realizes selective detection of UV or visible light in a single photodetector. In addition, the pyro-phototronic effect has been confirmed as an effective approach for enhancing the performance of photodetectors based on ZnO. The pyro-phototronic effect is carefully studied by comparing with a ZnO/Si heterojunction photodetector under UV and visible illumination at different bias voltages. To enhance the photodetector's wavelength selectivity, the parameters and structure are further optimized for the ZnO/NiO/SiO/Si heterojunction photodetector. The newly designed photodetector may be used to selectively detect and distinguish UV and visible illumination in a single photodetector.