Crystalline texture of gold nanoparticles formed on polished silicon using solid state and laser-induced dewetting

Abstract We aim to demonstrate the gold nanoparticle formation on silicon substrates by a time-consuming furnace process and a ns-short laser-induced process as methods that can be performed under ambient conditions. The properties of the particles are shown by means of electron microscopy and X-ray diffraction. We have found differences that suggest solid-state dewetting and liquid-state dewetting depending on the incorporated thermal energy. The short thermalization time of the laser process allows us to produce round-shaped polycrystalline nanoparticles. The nanoparticle formation by laser is dependent on the pulse energy and the pulse number. As a function of temperature from 300 to 1100 °C in a furnace, applied to thin gold films from 5 to 20 nm, the layers show complete dewetting of the substrate combined with the forming of nanoparticles with facette-like surfaces. Both methods show an improvement in the (111) texture with a small energy input up to the melting temperature of gold at 1060 °C compared to the original gold layer. However, with further increasing energy, the texture decreases again and falls below the level of the original layer. The particle size distributions, the crystallite sizes, and the intensity ratio of (111) and (002) reflexes are discussed.