Toward facile broadband photodetectors based on self-assembled ZnO nanobridge/rubrene heterointerface.

ZnO nanowire photodetectors have attracted much attention due to their excellent optoelectronic performances. However, the operating speed remains a challenge, and the scalability is also impeded by the uncontrolled transfer methods and sophisticated fabrication process. In this paper, we have fabricated an excellent ZnO nanobridge ultraviolet photodetector array by using a simple one-step method. The faster photoresponse speed and a broader response wavelength (from UV to visible range) have been achieved by constructing a type-II ZnO/rubrene heterointerface. Performance enhancement is believed to arise from the well-matching band alignment and highly efficient separation of photogenerated electron-hole pairs at the heterointerface. Our strategy provides a simple and promising route to develop cost-effective and highly sensitive UV-Vis photodetectors.