Temperature variation of the morphology of nanocluster ensembles in the Ge/Si(100) system

The morphological characteristics of hut-cluster ensembles formed in a Ge/Si(100) heteroepitaxial system have been studied as functions of the substrate surface temperature by theoretical methods and by atomic force microscopy. As the temperature increases from 420 to 500°C, the lateral size of nanoclusters with a square base (grown at the same rate of 0.0345 ML/s to a total coverage of 6.2 ML) grows from 12 to 20 nm, while their number density on the substrate surface drops from 5.6×10¹⁰ to 1.5×10¹⁰ cm⁻². Predictions of a kinetic model are in sufficiently good agreement with the experimental data.