Electrical and structural characterization of InAs/InGaAs quantum dot structures on GaAs

In this work we present the results of an electrical and structural characterization of molecular beam epitaxy (MBE) grown InAs/In0.15Ga0.85As quantum dot (QD) structures having InAs coverages of 2.0 and 3.0 ML that are, respectively, below and above the expected critical value for QD ripening in the InAs/GaAs system. The samples have been investigated by atomic force microscopy (AFM), transmission electron microscope (TEM), capacitance-voltage (C-V), and deep level transient spectroscopy (DLTS) techniques. The results obtained by the above techniques are compared and discussed.