Solution Processed ITO/ZnO QDs/TIPS -Pentacene/MoO High-Performance UV-Visible Photodetector

Abstract

This letter reports a TIPS-Pentacene (TIPS-P) based ultraviolet-visible (UV-Vis) photodetector using zinc oxide (ZnO) colloidal quantum dots (CQD) (of an average size of 2.00 nm) layer as the electron transport layer (ETL)-cum-UV absorption region and a MoOx layer for the hole transport layer (HTL). The overall device structure is ITO/ZnO CQDs/TIPS-P/ MoOx/Ag where indium tin oxide (ITO)-coated glass is the substrate and Ag is the anode contact of the device. ZnO CQDs and TIPS-P layers are grown by spin coating method while the MoOx layer and Ag contact electrode are grown by thermal evaporation method. Under -1 V reverse bias voltage, the photoresponse of the proposed device gives the maximum responsivity (R) of 217.24 A/W, detectivity (D) of {\sim }6.79 \times 10{12} cmHz {1/2} /W and external quantum efficiency (EQE) of 69811.93 % at 386 nm incident light of 46 ~\mu \text{W} /cm2 intensity while R57.34 A/W, D \sim 1.79 \times 10{1} cmHz {1/2} /W and EQE 11111.3 % were obtained at 640 nm incident light of 48.8 ~\mu \text{W} /cm2 intensity. © 1989-2012 IEEE.