Effects of growth parameters on the surface morphology of InAs quantum dots grown on GaAs/Ge/Si1−xGex/Si substrate

Electroluminescence at 1.3 µm from InAs/GaAs quantum dots monolithically grown on Ge/Si substrate by metal organic chemical vapor deposition

“…Additionally, after annealing, the surface morphology of the GaAs buffer layer was maintained, but at a higher annealing temperature (above 600 °C), an increase in roughness was observed together with the formation of large surface pits with a width of ∼350 nm and a depth of ∼90 nm (not shown here). The QDs formed on such a rough surface will have a large size fluctuation, leading to a board PL emission, along with the formation of high-density of coalescence dots, 23) and the QD PL intensity from such a sample is expected to be low [Fig. 2(b) (pink curve)].…”