Lateral ZnO nanowire growth on a planar substrate using a growth barrier

In this work, we present a technique to confine zinc oxide ( ZnO) nanowires to lateral growth while suppressing nanowire growth on the top surface of a planar substrate through the use of a growth barrier. Physical-vapour-deposited silicon dioxide and spin-on-glass dielectric were evaluated, and both have proven themselves as effective growth barriers. Through a simple oxidation process, ZnO nanowires, with typical diameters in the range of 20 - 40 nm, will grow laterally from selectively exposed zinc edges on otherwise encapsulated zinc lines. X-ray diffraction measurements show that the as-grown nanowires belong to the crystalline hexagonal-structured ZnO. This simple and cost-effective fabrication process, coupled with its process compatibility with existing silicon technology and its scalable nature, is a viable processing technique to selectively grow lateral ZnO nanowires on a planar substrate, with potential applications in nanowire devices.