Highly aligned vertical GaN nanowires using submonolayer metal catalysts

A method for fabricating vertically oriented nanowires on a substrate, the method comprising:

• depositing up to approximately a monolayer of catalyst metal atoms on a surface of a crystallographic template substrate;
• heating the crystallographic template substrate to induce surface diffusion of the catalyst metal atoms to form a plurality of metal nanoclusters;
• and
• reacting gallium atom precursor molecules and nitrogen precursor molecules at the metal nanoclusters to form vertically oriented single-crystal gallium nitride nanowires epitaxially aligned with the crystallographic template substrate, wherein the ratio of nitrogen precursor molecules to gallium atom precursor molecules is greater than 1.