Abstract:
The distinct roles of zinc oxide (ZnO) and zinc (Zn) seed layers in the growth of
vertically aligned high-quality zinc oxide (ZnO) nanorods by the sonochemical method were
investigated. ZnO nanorods were grown on p-type Si (111) with {Ti (10 nm)/ZnO (85 nm)}, {ZnO
(85 nm)}, {Ti (10 nm)/Zn (55 nm)} and {Zn (55 nm)}. Ti (10 nm) was incorporated as the buffer
layer. All depositions were carried out using RF-sputtering. The effects of the seed layers on the
growth of vertically aligned high-quality ZnO nanorods (NRs) were systematically studied using Xray
diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive Xray
(EDX) analysis and transmission electron microscopy (TEM). The results indicated that the
ZnO nanorods synthesized using ZnO (85 nm) as seed layer, with and without the Ti buffer layer,
have better average aspect ratio than those synthesized using Zn (55 nm) as seed layer. Therefore,
ZnO serves as a potential and preferable seed layer for the synthesis of vertically aligned highquality
ZnO nanorods with lower compressive strains. Furthermore, the lattice mismatch between
ZnO nanorods, seed layer and Si substrates was reduced with the introduction of thin Ti (10 nm) as
a buffer layer. In general, the type and thickness of seed layer are key parameters to synthesize high
quality ZnO nanorods
