Resonant tunneling spectroscopy of InAs quantum dots buried in the GaAs

We report the direct electron tunneling spectroscopy of bound states of InA s quantum dots buried in a GaAs layer in the vicinity of the GaAs surface. Several distinct peaks were assigned to tunneling through dot confined stat es by analyzing the first- and second-derivative signals. From the diamagne tic shift of the bound states, which were extracted from the tunneling prob ability fitting, the spatial extent of the electron wave function in the do t was estimated to be 123 Angstrom which agrees well with the estimated val ue based on AFM measurement result. (C) 1999 Published by Elsevier Science B.V. All rights reserved.