Fabrication of nanostructures by hydroxylamine seeding of gold nanoparticle templates

Hydroxylamine-seeding of colloidal gold particles has been used to fabricate gold nanostructures on a SiO₂ substrate. Gold nanoparticles (15 nm diameter) were randomly deposited on a SiO₂ surface that had been modified with aminopropyltrimethoxysilane (APTS). The nanoparticles were then manipulated using a scanning force microscope (SFM) tip to produce 1-D templates for gold deposition. We demonstrate the utility of this approach by fabricating a gold nanowire by using 13 nanoparticles as a template. The junction between joined (coated) particles was examined by mechanical manipulation, and homogeneous deposition was shown to form stable structures. This approach was also used to fabricate nanostructures in a small gap between two gold electrodes. Particles were pushed into the gap, and then gold deposition was used to "connect" the particles and electrodes. Although the particular structure tested was not electrically connected to the electrode, we suggest that this approach will be useful in tackling the difficult problems associated with electrically connecting nano- to microscale structures.