Ballistic electron emission microscopy/spectroscopy of InAs/GaAs quantum dots in GaAs/AlGaAs heterostructure grown by MOVPE and MBE

0371834 - FZÚ 2012 CZ eng A - Abstract
Vaniš, Jan - Walachová, Jarmila - Šroubek, Filip - Pangrác, Jiří - Vyskočil, Jan - Hulicius, Eduard - Hospodková, Alice
Ballistic electron emission microscopy/spectroscopy of InAs/GaAs quantum dots in GaAs/AlGaAs heterostructure grown by MOVPE and MBE.
NANOCON 2011. Conference Proceedings. Ostrava: Tanger Ltd, 2011. s. 77. ISBN 978-80-87294-23-9.
[NANOCON 2011. International Conference /3./. 21.09.2011-23.09.2011, Brno]
R&D Projects: GA ČR GAP102/10/1201; GA ČR GA202/09/0676
Institutional research plan: CEZ:AV0Z10100521; CEZ:AV0Z20670512
Keywords : BEEM * BEES * MOVPE * QD
Subject RIV: BM - Solid Matter Physics ; Magnetism

Same structures with self-assembled InAs quantum dots (QDs) were prepared by low pressure metal-organic vapour phase epitaxy (MOVPE) and molecular beam epitaxy (MBE). One single layer of InAs QDs confined between thin GaAs layers were embedded in ternary AlGaAs material. Buffer and capping GaAs layers were also used. During MOVPE growth process reflectance anisotropy spectroscopy were measured for growth control. Grown structures were examined by ballistic electron emission microscopy. On MOVPE and MBE grown QDs of similar size, found by ballistic electron emission measurement, ballistic current-voltage characteristics were measured. In more detail spectroscopy characteristics with its derivations (minima in derivation of the current-voltage characteristic present quantum levels in the QD) in the voltage range where the presence of resonance states of QD is expected are given. Differences in the intensities and sharpnesses of the QD levels for MBE and MOCVD grown QDs are observed.
Permanent Link: http://hdl.handle.net/11104/0205259