Molecular beam epitaxial growth of InSb, GaSb, and AlSb nanometer-scale dots on GaAs

Thin layers of InSb, GaSb, and AlSb were grown on GaAs substrates by molecular beam epitaxy. Atomic force microscopy was used to examine surface morphology as a function of growth temperature and monolayer coverage. For each material, conditions were found which resulted in Stranski–Krastanov growth with the strain-induced formation of nanometer-scale dots. Relatively uniform distributions of dots form in a temperature window near the congruent sublimation temperature for both InSb and GaSb. In the case of InSb, deposition of 2 monolayers at 430 °C produced a surface with 3×109/cm2 dots with heights of 58±5 Å and diameters of 600±50 Å.