Controlling the growth of single crystal ZnO nanowires by tuning the atomic layer deposition parameters of the ZnO seed layer

Abstract

Semiconducting nanowires (NWs) offer exciting prospects for a wide range of technological applications. The translation of NW science into technology requires reliable high-quality large volume production. This study provides an in-depth investigation of the parameters using an atomic layer deposition (ALD) system to grow zinc oxide (ZnO) seed layers followed by the chemical bath deposition of ZnO nanowires (NWs) to demonstrate the low-cost production of uniform single crystal wurtzite 2 phase ZnO NWs that is scalable to large area substrates. The seed layer texture and the morphology of the NWs grown were systematically investigated using atomic force microscopy (AFM) as a function of the seed layer deposition parameters. It is shown that the NWs growth orientation can be controlled by tuning the seed layer deposition parameters while maintaining the same chemical bath deposition conditions. Likewise, the diameters and the surface densities of the NWs varied from 23 to 56 nm and 40 to 327 NWs/µm 2 , respectively. Significantly, the relationship between the seed layer structure and the NW density indicates a clear correlation between the density of seed layer surface features and the resulting surface NW density of nanowires grown.

Optical properties and carrier dynamics in Co-doped ZnO nanorods

“…The ZnO NRs were grown on the textured seed layers by chemical bath deposition on a 25 nm thick ZnO seed layer deposited by atomic layer deposition on a range of different substrates such as quartz, ITO-coated glass and silicon. 26 The seed layers were immersed in a solution containing equimolar concentrations (25 mM) of zinc nitrate hexahydrate and hexamethylenetetramine in water, which was subsequently heated to 90 °C for 6 hours. Afterwards, the as-grown NRs were thoroughly washed with deionized water and blow dried under a N 2 stream.…”

Transition from Metal-Rich to N-Rich Growth for Core–Shell InGaN Nanowires on Si (111) at the Onset of In Desorption

“…From P1 to P6, the columns get denser and more connected, revealing the evolution from well-separated core–shell InGaN NWs at P1 and P3 to a more compact columnar layer at P5 and a more cluster-like coalesced compact columnar layer at P6. This is quantified by the surface coverage of the columns plotted in Figure c and the root-mean-square (rms) surface roughness in Figure d, deduced from the AFM images and line profiles − shown in Supporting Information Figure S1. This is the first hint to reducing N flux from P1 to P6, revealing the general trend of columnar growth for higher N flux to more compact, planar growth for lower N flux toward metal-rich growth, provided the Ga and In fluxes do not change much.…”

Cobalt-Doped ZnO Nanorods Coated with Nanoscale Metal–Organic Framework Shells for Water-Splitting Photoanodes

“…The ZnO:Co NRs are grown by a two-step process consisting of the spin-coating of a ZnO seed layer and subsequent NR growth with the well-established chemical bath deposition , (CBD). Cobalt is introduced into the growth solution, where it is incorporated into the ZnO lattice, substituting Zn atoms during growth through competitive reactions, as shown by the X-ray diffraction and X-ray photoelectron spectroscopy (XPS) results in Figures S1 and S2 of the Supporting Information.…”