Transparent NiO/ZnO heterojunction for ultra-performing zero-bias ultraviolet photodetector on plastic substrate

All transparent photoelectric devices were achieved for the highly-performing photodetectors. The high transparent heterojunction photodetector of the configuration of NiO/ZnO/ITO/PET was realized by using the solid-state sputtering method. All metal oxide layers were formed at room temperature to be applied on the plastic substrate. The ITO layer was directly coated on the PET substrate to work as a transparent conductor. To form the transparent p/n junction, p-type NiO was reactively sputtered following by n-type ZnO deposition onto the ITO. This high visible-range transparent (74.8%) photodetector is extremely sensitive to detect the tiny UV light density of 10 μW/cm² with the ultra-fast photoresponse time (19 μs) and high-photoresponse ratio (1944) due to the merit of excitonic absorption. The design scheme of zero-bias operating transparent heterojunction can be applied for visible electronic devices and solar cells. - Highlights: • High transparent (74.8%) and ultra-performing photodetector was achieved. • All metal oxides were deposited on a plastic substrate at room temperature. • Heterojunction photodetector is configuring of p-type NiO and n-type ZnO. • Record-fast photoresponse 19 μs was achieved by self-operating mode.