Single CdS nanowire photodetector fabricated by FIB

In this paper, a photodetector based on single cadmium sulfide (CdS) nanowire was fabricated using focused ion beam (FIB) technique. The nanowire manipulation, transferring and electrode fabrication process by the FIB and its influence on the photodetector performance were studied. CdS nanowire was synthesized by Vapor-Phase-Transport (VPT) method. CdS powder was thermally evaporated at 950 °C in the Argon (Ar) gas as the source material. High Resolution Transmission Electron Microscope (HRTEM) and X-ray Diffraction (XRD) experiment results showed that the nanowire presented wurtzite CdS structure and good crystal quality. The photoresponse time and recovery time of the photodetector were 150 ms and 53 ms, respectively. The photosensitivity was 2.83, and the low sensitivity was caused by the deposition of Ga on the surface of the nanowire and electrode gap during the FIB fabricating process.