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$_ x$ N$_ y$ nanostrips on top of nanostructures can yield, via metal-organic chemical-vapor deposition, GaN(10$\bar1$2) layers. An additional SiC buffer layer makes it possible to obtain GaN(10$\bar1$1) layers with a full-width at half-maximum of the diffraction-curve of $\omega_\theta\approx$ 35' arcmin. It is found that the luminescence properties of the semipolar layers are mostly due to basal plane stacking faults BSF$_ S$ -I$_1$, in contrast to polar layers in which these properties are mostly due to the recombination of excitons.