Structural Properties and Energy Spectrum of Novel GaSb/AlP Self-Assembled Quantum Dots
Demid S. Abramkin,
Mikhail O. Petrushkov,
Dmitrii B. Bogomolov,
Eugeny A. Emelyanov,
Mikhail Yu. Yesin,
Andrey V. Vasev,
Alexey A. Bloshkin,
Eugeny S. Koptev,
Mikhail A. Putyato,
Victor V. Atuchin,
Valery V. Preobrazhenskii
Affiliations
Demid S. Abramkin
Laboratory of Molecular-Beam Epitaxy of A3B5 Compounds, Institute of Semiconductor Physics, SB RAS, Novosibirsk 630090, Russia
Mikhail O. Petrushkov
Laboratory of Physical Bases of Semiconductor Heterostructures Epitaxy, Institute of Semiconductor Physics, SB RAS, Novosibirsk 630090, Russia
Dmitrii B. Bogomolov
Laboratory of Physical Bases of Semiconductor Heterostructures Epitaxy, Institute of Semiconductor Physics, SB RAS, Novosibirsk 630090, Russia
Eugeny A. Emelyanov
Laboratory of Physical Bases of Semiconductor Heterostructures Epitaxy, Institute of Semiconductor Physics, SB RAS, Novosibirsk 630090, Russia
Mikhail Yu. Yesin
Laboratory of Molecular-Beam Epitaxy of Elementary Semiconductors and A3B5 Compounds, Institute of Semiconductor Physics, SB RAS, Novosibirsk 630090, Russia
Andrey V. Vasev
Laboratory of Physical Bases of Semiconductor Heterostructures Epitaxy, Institute of Semiconductor Physics, SB RAS, Novosibirsk 630090, Russia
Alexey A. Bloshkin
Department of Physics, Novosibirsk State University, Novosibirsk 630090, Russia
Eugeny S. Koptev
Laboratory of Nonequilibrium Semiconductor Systems, Institute of Semiconductor Physics, SB RAS, Novosibirsk 630090, Russia
Mikhail A. Putyato
Laboratory of Physical Bases of Semiconductor Heterostructures Epitaxy, Institute of Semiconductor Physics, SB RAS, Novosibirsk 630090, Russia
Victor V. Atuchin
Laboratory of Optical Materials and Structures, Institute of Semiconductor Physics, SB RAS, Novosibirsk 630090, Russia
Valery V. Preobrazhenskii
Laboratory of Physical Bases of Semiconductor Heterostructures Epitaxy, Institute of Semiconductor Physics, SB RAS, Novosibirsk 630090, Russia
In this work, the formation, structural properties, and energy spectrum of novel self-assembled GaSb/AlP quantum dots (SAQDs) were studied by experimental methods. The growth conditions for the SAQDs’ formation by molecular beam epitaxy on both matched GaP and artificial GaP/Si substrates were determined. An almost complete plastic relaxation of the elastic strain in SAQDs was reached. The strain relaxation in the SAQDs on the GaP/Si substrates does not lead to a reduction in the SAQDs luminescence efficiency, while the introduction of dislocations into SAQDs on the GaP substrates induced a strong quenching of SAQDs luminescence. Probably, this difference is caused by the introduction of Lomer 90°-dislocations without uncompensated atomic bonds in GaP/Si-based SAQDs, while threading 60°-dislocations are introduced into GaP-based SAQDs. It was shown that GaP/Si-based SAQDs have an energy spectrum of type II with an indirect bandgap and the ground electronic state belonging to the X-valley of the AlP conduction band. The hole localization energy in these SAQDs was estimated equal to 1.65–1.70 eV. This fact allows us to predict the charge storage time in the SAQDs to be as long as >>10 years, and it makes GaSb/AlP SAQDs promising objects for creating universal memory cells.
