Epitaxy of GaN(0001) and GaN(10$\bar1$1) layers on Si(100) substrate

Two different approaches to epitaxy of 4-$\mu$m-thick layers of polar GaN(0001) and semipolar GaN(10$\bar1$1) on a $V$-shaped nanostructured Si(100) substrate with nanometer-thick SiC and AlN buffer layers have been experimentally demonstrated. The GaN(0001) layers were synthesized by hydride vapor-phase epitaxy, and GaN(10$\bar1$1) layers, by metal-organic vapor-phase epitaxy, with the growth completed by hydride vapor-phase epitaxy. It was shown that layers of the polar GaN(0002) have a longitudinal elastic stress of -0.45 GPa and the minimum full width at half-maximum of the X-ray diffraction rocking curve $\omega_\theta\sim$ 45 arcmin, whereas for the semipolar GaN(10$\bar1$1), these values are -0.29 GPa and $\omega_\theta\sim$ 22 arcmin, respectively. A conclusion is drawn that the combined technology of semipolar gallium nitride on a silicon (100) substrate is promising.