Self-assembled zinc blende GaN quantum dots grown by molecular-beam epitaxy

Zinc blende (ZB) GaN quantum dots have been grown by plasma-assisted molecular-beam epitaxy on AlN buffer layers using 3C-SiC(001) substrates. The two- to three-dimensional growth mode transition is studied by following the evolution of the reflection high-energy electron diffraction pattern. ZB GaN island layers are further examined by atomic force microscopy and transmission electron microscopy, extracting a mean island height of 1.6 nm and a mean diameter of 13 nm at a density of ${\text{1.3×10}}^{11} {\mathrm{cm}}^{\mathrm{-2}}.$ Embedded ZB GaN quantum dots show strong ultraviolet photoluminescence without any thermal quenching up to room temperature.