Effect of the Seeding Thickness on the Growth of ZnO Nanorods prepared by CBD

Abstract

Zinc Oxide (ZnO) nanostructure (NS), with nanorods (NRs) forward-facing alignment were deposited by chemical bath deposition (CBD) method on seeded glass substrates. Two different ZnO seed layer thickness, 100 nm and 200 nm, prepared by RF sputtering were employed to investigate the effect of seed layer thickness on the characteristics of the grown ZnO NRs. The investigations on physical, structural, and optical properties were carried out through field emission scanning electron microscope (FESEM) with integrated energy dispersive X-ray (EDX), X-Ray Diffraction (XRD), and UV and visible (UV-Vis) analyses. The morphological results reveal that with a thicker seed layer, the grown NRs diameter increased double while the NRs height was maintained at 1.5 μm. From EDX, the stoichiometric ratios of Zn:O were mostly towards 1:1. While the XRD evaluates that the preferred structure was wurtzite hexagonal with c-axis orientation along (002) plane. The UV-Vis analysis showed the increased in optical band gap energy closes to the bulk ZnO at 3.37 eV, for the ZnO NRs grown on the thicker seed layer. The obtained results illustrated high quality single-crystal ZnO NRs with different diameters were realized by only adjusting the seed layer thickness.