Investigation of defects created by growth of InAs quantum dots in GaAs

Defects created by self-organized InAs quantum dot growth in a GaAs matrix were investigated. Growth of the quantum dots was found to enhance strongly the tendency towards inhomogeneous growth. The inhomogeneity seems to stem from point defect clusters generated in the vicinity of a molecular beam epitaxy (MBE)/atomic layer MBE (ALMBE) interface. The point defects identified are characteristic of MBE and ALMBE GaAs layers. The InAs quantum dot states and interface states are not clearly detected since they are located in a depleted layer surrounding the point defects clusters.