Highly ordered uniform quantum dots induced by ion sputtering

Self-organized hexagonally ordered quantum dot patterns are produced on GaSb (100) and InSb (100) surfaces by low energy Ar+-ion sputtering at normal angle of incidence. The QDs are crystalline, exhibiting narrow size distributions with diameters from 17 - 80 nm depending on sputter conditions, densely packed with densities as high as 2 x 10(11) cm(-2). The origin of the QD formation is attributed to the interplay of two surface processes during ion bombardment: ion induced surface roughening, provoked by the curvature dependent sputter yield and balanced by surface diffusive processes. The observed QD patterns obtained at different sputter conditions show that the formation mechanism can be described by the Kuramoto-Sivashinsky equation. The dominant diffusive process emerges to be effective ion induced without any mass transport on the surface, inherent to the sputtering process.