Growth and characterization of HgSe:Fe quantum dots

Applying three different sophisticated growth methods using MBE we succeeded in growing unburied and buried quantum-dot structures of HgSe:Fe on a ZnSe/GaAs buffer/substrate system in (001) orientation. For the buried quantum dots the buffer/substrate system was specially prepared by a thermal desorption process resulting in the generation of surface dips acting as a mould for the quantum dots. The advantage of this method lies in the possibility of easily removing the wetting layer without affecting the dots. In this way the usually strong influence of the wetting layer in the experimental data for the highly conductive HgSe:Fe could nearly completely be suppressed. The growth process was in situ controlled by RHEED providing detailed information on the structural properties. The ex situ structural investigation used AFM and SEM. The characterization of the electronic properties was performed by IR megagauss-magneto spectroscopy.