Nucleation and growth of erbium clusters on amorphous carbon substrates. I. Cluster size and spatial distribution

The size and spatial distribution of erbium clusters during deposition onto amorphous carbon (a-C) are investigated. The effect of interparticle forces in producing preferred spacings between clusters and the influence of such forces on the coalescence are determined. The radial distribution function P(r) and nearest neighbour distances show that the distribution of erbium clusters on a-C is non-random. It is shown that the mobility of erbium clusters decreases with increasing size, and there is an 'equilibrium' for clusters of diameter 40-50 AA.