SKM 2021 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

HL: Fachverband Halbleiterphysik

HL 8: Poster Session II

HL 8.7: Poster

Tuesday, September 28, 2021, 10:00–13:00, P

Wafer Scale Density Modulation of Self-Assembled Quantum Dots by Epitaxial Surface Roughness Control — •Nikolai Bart, Nikolai Spitzer, Peter Zajac, Marcel Schmidt, Andreas D. Wieck, and Arne Ludwig — Ruhr-Universität Bochum, Lehrstuhl für Angewandte Festkörperphysik, Universitätsstraße 150, 44801 Bochum, Germany

The effect of nanoscale roughness of GaAs surfaces on the nucleation of self-assembled InAs quantum dots (QD) is investigated with photoluminescence (PL) spectroscopy. We control the roughness in-situ by simple epitaxial layer-by-layer growth: Depositing integer (fractional) values of GaAs monolayer thicknesses yields a smooth (rough) surface. We report significant differences in both PL intensity and QD surface density at the critical threshold of nucleation. By growing GaAs thickness gradients, we create and control various density modulation patterns on whole 3-inch wafers. Moreover, we investigate the influence of surface annealing time and temperature on the modulation and demonstrate how to utilize this mechanism for density control of high quality single QD photonic device wafers.