Nanoplasmonic enhanced ZnO/Si heterojunction metal-semiconductor-metal photodetectors

This paper presents a nanoplasmonic enhanced ZnO/Si heterojunction metal-semiconductor-metal (MSM) photodetector (PD). By depositing different thicknesses of Ag thin film and annealing at a moderate temperature, well-defined silver (Ag) nanoparticles (NPs) with different diameters, densities, and size distributions were produced on the surface of ZnO/Si MSM photodetector devices. By tuning the characteristics of these NPs, a higher-performance ZnO/Si MSM photodetector has been realized. The photocurrent of the detector with NPs was increased by 160% to 680%, depending on the applied voltage. The spectral photocurrent enhancement by a factor of 7 to 18 was broadband from 350 nm to 850 nm.