ABSTRACTThree-dimensional islands of InP have been reproducibly grown in the Stranski-Krastanow growth mode on Si (001) and (111) by using metal-organic vapor phase epitaxy in order to obtain nanometer-scale quantum dots. Atomic-force microscopy was used to determine the morphology of the samples and to evaluate the dimensions of the islands. Formation of three-dimensional islands with densities as high as 2.5×10¹⁰ cm⁻² and small sizes have been observed. The evolution of island morphology is explained in terms of strain-relaxing mechanisms at the first stages of InP/Si heteroepitaxy.