Growth of compositionally uniform InxGa1−xN layers with low relaxation degree on GaN by molecular beam epitaxy

Abstract 500 nm-thick In x Ga 1 − x N layers with x = 0.06–0.14 are grown using plasma-assisted molecular beam epitaxy, and their properties are assessed by a comprehensive analysis involving x-ray diffraction, secondary ion mass spectrometry, and cathodoluminescence as well as photoluminescence spectroscopy. We demonstrate low degrees of strain relaxation (10% for x = 0.12), low threading dislocation densities ( 1 × 10 9 cm − 2 for x = 0.12), uniform composition both in the growth and lateral direction, and a narrow emission band. The unique sum of excellent materials properties make these layers an attractive basis for the top–down fabrication of ternary nanowires.