Atomic force microscopy and in situ-annealing X-ray diffraction study on template-stripped gold substrates for optimum self-assembled monolayer deposition

Highlights: • Optimizing deposition rate of gold on silicon to enhance flatness and grain size • X-ray diffraction measurements are performed in situ (during annealing) • Optimizing the annealing temperature in air to enhance surface state of gold • Optimizing the annealing time in air to enhance surface state of gold • Smooth gold substrate via template-stripping: root mean square roughness=2.1±0.4 Å Literature is well supplied with studies of gold deposit on mica for fabricating ultra-flat template-stripped gold surface. Gold on silicon has not received much attention. Our study optimizes the deposition rates, annealing temperatures and time to obtain a template-stripped gold surface with a very low roughness and large (111) oriented crystallites. Atomic force microscopy is performed in tapping and peak force mode to evaluate the surface roughness. The crystallite size is obtained from in situ X-ray diffraction measurements during annealing. We find out that a deposition rate of 0.2 nm/s with a 40 min annealing at 400°C gives the best result (0.21±0.04) nm.