Formation of Ag and Co nanowires at the step of the Cu(100) vicinal surfaces: A kinetic Monte Carlo study

We use Kinetic Monte-Carlo (KMC) simulations based on the solid-on-solid model [Phys. Rev. B 95 (2017) 085404] to determine optimum growth parameters, deposition rate F and substrate temperature T for growing “perfect” Co and Ag nanowires on Cu(100) vicinal surfaces. The heteroepitaxial growth of mono-atomic wires on a Cu surface is performed over a large range of temperature, varying between 50 K and 575 K. We found different temperature ranges where 'perfect' mono-atomic wires are formed at the step-edge of Cu vicinal surface, such as [200 K575 K] for Ag/Cu and [425 K525 K] for Co/Cu. Different atomistic mechanisms may intervene in favoring adatom attachment to surface steps, thus allowing nanowires growth. Here we have focused on the effect of the Ehrlich-Schwoebel barrier; a physical property that determines the mobility of adatomes across surfaces kinks and steps. We discussed how the magnitude of this barrier affects the filling rate and the uniformity of Ag and Co nanowires.