The difference in the type of zinc oxide nanostructures depending on the growth layer

Abstract

In this study, RF-sputtering was used to hydrothermally produce zinc oxide nanorods (ZnO NRs) on the seed layer of ZnO/Glass substrates. at different thicknesses (t1 = 1135 nm, t2 = 1306 nm, t3 = 1437 nm, t4 = 1533 nm). The structural properties were studied by X-ray diffraction, which showed that ZnO NRs and the seed layer films are polycrystalline with the same preferred reflection for the (002) plane, and the grain size of the seed layer ranges between 19.51 nm and 30.45 nm for thicknesses t1 and t4, respectively. The measurements of the FESEM showed aspect ratios for ZnO NRs ranging from 3.03 for t1 to 4.9 for t4, with growth in different shapes: ZnO NR rods for t1, flowers and rod-like shapes for thicknesses of t2 and t3, and hexagonal-rod-like shapes in t4. Optical measurements showed a decrease in the transmittance and an increase in the energy gap values with increasing thickness.