Misfit dislocation reduction in InGaAs epilayers grown on porous GaAs substrates

0431319 - FZÚ 2015 RIV NL eng J - Článek v odborném periodiku
Dimitrakopulos, G.P. - Bazioti, C. - Grym, Jan - Gladkov, Petar - Hulicius, Eduard - Pangrác, Jiří - Pacherová, Oliva - Komninou, Ph.
Misfit dislocation reduction in InGaAs epilayers grown on porous GaAs substrates.
Applied Surface Science. Roč. 306, Jul (2014), s. 89-93. ISSN 0169-4332. E-ISSN 1873-5584
Grant CEP: GA MŠMT 7AMB12GR034
Institucionální podpora: RVO:68378271 ; RVO:67985882
Klíčová slova: compound semiconductors * InGaAs * porous substrate * misfit dislocations * strain
Kód oboru RIV: BM - Fyzika pevných látek a magnetismus
Impakt faktor: 2.711, rok: 2014

Elastic accommodation of heteroepitaxial layers beyond their critical thickness is crucial for the reduction of misfit dislocations. In this work, pore networks were introduced electrochemically in GaAs substrates in order to modify their mechanical responses. InxGa1−xAs epilayers with nominal indium contents up to x = 0.20 were then deposited by MOVPE, and were compared to similar epilayers grown on nonporous GaAs. Strain relaxation and defect introduction were studied by TEM observations, x-ray diffraction, and photoluminescence measurements. It was found that the porous substrates acted to reduce the density of misfit dislocations, thereby increasing the epilayer critical thickness. The InGaAs epilayers retained a significantly higher amount of elastic strain compared to ones grown on nonporous GaAs. The onset of plasticity was mediated by the pores, which acted as nucleation sites for 60° dislocations that glided toward the interface.
Trvalý link: http://hdl.handle.net/11104/0235904