Structural and photoluminescent properties of low temperature InAs buffer layer grown by MOVPE on GaAs substrates

0398725 - FZÚ 2014 CZ eng A - Abstrakt
Hulicius, Eduard - Komninou, Ph. - Gladkov, Petar - Karakostas, Th. - Pangrác, Jiří
Structural and photoluminescent properties of low temperature InAs buffer layer grown by MOVPE on GaAs substrates.
NANOCON 2013. 5th International Conference Proceedings. Ostrava: TANGER Ltd, 2013. s. 75-75. ISBN 978-80-87294-44-4.
[NANOCON 2013. International Conference /5./. 16.10.2013-18.10.2013, Brno]
Grant CEP: GA ČR GA13-15286S; GA MŠMT 7AMB12GR034; GA MŠMT(CZ) LM2011026
Institucionální podpora: RVO:68378271 ; RVO:67985882
Klíčová slova: InAs/GaAs heterostructures * MOVPE * structural properties * TEM characterization * PL characterization
Kód oboru RIV: BM - Fyzika pevných látek a magnetismus

Epitaxial growth of InAs on semi-insulating GaAs was subject of various attempts to reduce the influence of ~7% lattice mismatch on the InAs layer properties. The most cost effective and promising method appears to be the growth by MOVPE of low temperature buffer InAs layer at ~400°C prior to the growth of a thick InAs layer on top of the LTB at ~600°C. We have found that a predominant part of the threading dislocations generated at the interface annihilate within the first 0.3 μm. The LTB and GaAs preserve exact epitaxial orientation. The average misfit dislocation spacing is 6.15 nm, proving that the LTB-InAs/GaAs interface is nearly completely relaxed. The LTB-InAs layer is n-type with carrier concentration of the order of 5x1016 cm-3 and hence can serve as a bottom contact layer. The morphology of unintentionally doped InAs layer grown upon the LTB at 600°C shows sub-nanometer flatness and carrier concentration in the order of 5 x 1015 cm-3.
Trvalý link: http://hdl.handle.net/11104/0226162