Electronic structure of self-assembled InAs quantum dots in GaAs matrix

Capacitance–voltage characteristics have been measured at various frequencies and temperatures for structures containing a sheet of self-assembled InAs quantum dots in both $\mathrm{n-}\mathrm{GaAs}$ and $\mathrm{p-}\mathrm{GaAs}$ matrices. Analysis of the capacitance–voltage characteristics shows that the deposition of 1.7 ML of InAs forms quantum dots with electron levels 80 meV below the bottom of the GaAs conduction band and two heavy-hole levels at 100 and 170 meV above the top of the GaAs valence band. The carrier energy levels agree very well with the recombination energies obtained from photoluminescence spectra.