With a goal of development of a high performance medium for optoelectronic devices, formation of InAs self-assembled quantum dots (QDs) in GaAs/AlAs short period superlattice was studied using primarily in situ molecular beam epitaxy techniques including reflection high-energy electron diffraction and Auger electron spectroscopy. The processes of formation, decay of QDs and overgrowth of wetting InAs layers were analyzed with the emphasis on the role of AlAs or GaAs capping layers. InAs critical coverage for QD formation on GaAs and AlAs surfaces was measured as a function of temperature, and diffusion coefficients of In adatoms were estimated. QD decay was studied, activation energy for the process was found to be 0.8 and 2.3 eV for GaAs and AlAs surfaces, respectively, indicating that QD decay process is likely driven by In intermixing with the substrate for GaAs surface and by evaporation of In from the AlAs surface. Intermixing of InAs with the capping layers was studied at growth temperatures. Typical InAs redistribution thickness was estimated as 6 ML at 475 degrees C, same for AlAs and GaAs, with In segregation efficiency R=0.86 in both cases. (c) 2005 American Vacuum Society.