ZnO UV Photodetectors Modified by Ag Nanoparticles Using All-Inkjet-Printing

To further improve the performance of all-inkjet-printing ZnO UV photodetector and maintain the advantages of inkjet printing technology, the inkjet printing Ag nanoparticles (NPs) were deposited on the inkjet printing ZnO UV photodetector for the first time. The inkjet printing Ag NPs can passivate the surface defects of ZnO and work as surface plasmons from the characterization of photoluminescence (PL), X-ray photoelectron spectroscopy (XPS), and finite difference time domain method (FDTD) simulation. The normalized detectivity (D^*) of the Ag NP-modified detector reaches to 1.45 × 10¹⁰ Jones at 0.715 mW incident light power, which is higher than that of 5.72 × 10⁹ Jones of the bare ZnO photodetector. The power-law relationship between the photocurrent and the incident light power of the Ag NP-modified ZnO detector is I_pc ∝ P^2.34, which means the photocurrent is highly sensitive to the change of incident light power.