Enhanced ultraviolet-visible light responses of phototransistors based on single and a few ZrS3 nanobelts

Abstract

Phototransistors based on single and three ZrS₃ nanobelts were fabricated on SiO₂/Si wafers by photolithography and the lift-off technique, respectively, and their light-induced electric properties were investigated in detail. Both the devices demonstrate a remarkable photoresponse from ultraviolet to near infrared light. The photoswitch current ratio (PCR) of the single-nanobelt phototransistor is 13 under the illumination of 405 nm light with an optical power of 10.5 mW cm⁻² at a bias of 5 V, while the PCR of the three-nanobelt device is 210 under the illumination of 405 nm light with an optical power of 5.57 mW cm⁻² at a bias of 1 V. On comparison of the photoresponses under the same conditions, the latter is found to be superior to the former, and both the devices show a much better photoresponse than the reported flexible ZrS₃-nanobelt-film photodetector.