A mutilayer structure of self-assembled GaSb/GaAs quantum dots (QDs) has been grown for the first time by metalorganic chemical vapor deposition (MOCVD) in the Stranski-Krastanow (S-K) growth mode. Evidence of the growth of the self-assembled quantum dots was provided using transmission electron microscopy. This study shows that the GaSb/GaAs heterostructure is well controlled and there is no sign of the intermixing that often occurs for this system. The existence of the quantum dots and of a wetting layer was also supported by photoluminescence spectra. These results open the way to the realization of GaSb/GaAs QD superlattice structures in which the islands have equal size in all layers. The QD structures also provide an opportunity for studying electronic coupling between islands. (C) 2003 Elsevier Science B.V. All rights reserved.