We report on the x-ray analysis of non-capped InAs/AlAs(0 0 1) quantum dot systems grown at temperatures ranging from 480 up to 530 °C. A constant amount of InAs has been deposited resulting in a growth stage where coherently strained dots and plastically relaxed clusters coexist. It is found that with an increase in deposition temperature the average size of elastically strained dots increases without changes in their chemical composition and surface density. The observed process is in accordance with the InAs volume decrease stored in plastically relaxed clusters. The results establish the crucial role of strain-induced material intermixing between strained InAs dots and the AlAs substrate over the investigated growth temperature range.