Epitaxial lateral overgrowth of InN by rf-plasma-assisted molecular-beam epitaxy

The orientation-dependent lateral growth of InN was studied and the epitaxial lateral overgrowth (ELO) of InN by rf-plasma-assisted molecular-beam epitaxy was demonstrated for the first time using stripe molybdenum (Mo)-mask-patterned sapphire (0001) substrates. Transmission electron microscopy observation revealed a high dislocation density of ∼5x10-9 cm-2 in the window region. By contrast, very few threading dislocations were observed in the wing region. In particular, there were no threading dislocations in the superficial layer of up to 3 μm width. An InN ELO sample exhibited narrow near-IR emission with a peak photon energy of 0.677 eV and a linewidth of 16.7 meV at 4 K.