Deformation of Semipolar and Polar Gallium Nitride Synthesized on a Silicon Substrate

Results from studying deformation are obtained for semipolar GaN(11–22) grown on a nanostructured Si(113) substrate and polar GaN(0001) grown on a flat Si(111) substrate. A comparison of the structures of semipolar and polar epitaxy reveals a drop in layer deformation resulting from the smaller difference between the coefficients of thermal expansion of the substrate and gallium nitride in the semipolar direction of the crystal than in the polar direction.