Properties of Semipolar GaN Grown on a Si(100) Substrate

Semipolar GaN layers synthesized on a nanostructured Si(100) substrate are studied. It is shown that using a Si(100) nanoprofile combined with Si_xN_y nanostrips on top of nanostructures can yield, via metal-organic chemical-vapor deposition, GaN(10$\overline{1}$2) layers. An additional SiC buffer layer makes it possible to obtain GaN(10$\overline{1}$1) layers with a full-width at half-maximum of the diffraction-curve of ω_θ ≈ 35′ arcmin. It is found that the luminescence properties of the semipolar layers are mostly due to basal plane stacking faults BSF_S-I₁, in contrast to polar layers in which these properties are mostly due to the recombination of excitons.