High performance of UV photodetectors by integration of plasmonic Ag nanoparticles on GaN

Abstract

High-performance ultraviolet photodetectors have attracted much attention due to their various potential applications from household to universal. On basis of this, in this work, a high – performance and photoresponse enhancement UV photodetector based on Ag NPs/GaN heterojunction was demonstrated. By incorporating of Ag nanoparticles, light confinement determined by Ag nanostructure offers an effective approach to break through the limitation of the light-mater interaction within the photoactive layers of photodetector. Various size and elemental composition of Ag NPs are fabricated on GaN lead to significant enhancement of photocurrent in UV photodetector. Consequently, an outstanding photoresponsivity of 89 A/W, external quantum efficiency of 2.8 × 103% at low bias voltage of 0.3 V were achieved. The improve photo-response of the Ag NPs-decorated GaN-based photodetector is attributed to the simultaneous effect of strong plasmon absorption, increased injection of hot electrons into the conduction band of GaN. This study will open up the direction to fabricate the high-performance UV photodetector.