Regensburg 2019 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

HL: Fachverband Halbleiterphysik

HL 42: Quantum dots and wires: Preparation and characterization

HL 42.5: Vortrag

Donnerstag, 4. April 2019, 16:15–16:30, H34

Heterointegration of III-V materials on silicon substrates using quantum dot strain relaxation layers — •Cedric Corley, Vitalii Sichkovskyi, and Johann Peter Reithmaier — Institute of Nanostructure Technologies and Analytics (INA), Technische Physik, CINSaT, University of Kassel, Germany

The heterointegration of III-V materials and Silicon is of significant interest, e.g. for telecommunication technology, but faces challenges due to threading defect generation at the GaAs/Si interface. Photoluminsecent emission (PL) from optically active Quantum Dots (QDs) embedded in a GaAs buffer layer grown on a Silicon substrate by Molecular Beam Epitaxy (MBE) is deteriorated by these dislocations. Peach-Koehler forces exerted from highly strained QDs grown in between the interface and the optically active layers can redirect the dislocations and thus compensate their impact on the optical properties. In the past, defect filtering by structures encompassing multiple (five or more) highly strained QD layers seperated by GaAs spacer layers has been shown. This contribution compares defect filtering in structures grown by MBE incorporating a various number of InAs QD layers. An efficient defect filtering can already be achieved by as few as two layers. The material quality is monitored by the optical emission properties of an In_0.5Ga_0.5As QD layer grown on top of the relaxation layer structure. The results are compared with a similar QD layer grown directly on a GaAs substrate showing similar PL properties in intensity and linewidth.