Investigation of Crystallized ZnSnO3 Nanoparticles for Ultraviolet Photodetectors

ZnSnO3 (ZTO) nanoparticles synthesized by a sol-gel method were spin-coated on p-Si substrates for the fabrication of UV photodetectors. After annealing the ZTO nanoparticles at 500 degrees C for 20 min, the ZTO films were crystallized in a pure N-2 atmosphere; film formation was confirmed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). From the photoluminescence measurement results, the crystallized ZTO films show the strongest emission peak at a wavelength of 381 nm (3.25 eV) with a full width at half maximum of 121 meV at room temperature. In order to show the UV-response of our samples, time-dependent photocurrents were observed. The crystallized ZTO films show a transient photocurrent curve and a decay time of 1.29 s, which indicates that crystallized ZTO nanoparticles can be used for UV photodetectors.