New buffer sublayers with crystal structure of cubic syngony for growing the heteroepitaxial films of nitride compounds of type A III B V on sapphire substrates

We propose the use of a buffer sublayer made of materials with crystal structure of cubic syngony to eliminate 30° in-plane rotation of (0001) heteroepitaxial wurtzite type A III B V nitride films with respect to the (0001) or (11 0) working surface of the sapphire substrate. In these cases, the lattice parameter mismatch between the sapphire substrate surface and the semiconductor film is much smaller, and the cleavage planes of the sapphire and the semiconductor films with wurtzite structure forming the active region of a heterolaser are parallel. It is shown experimentally that using, for instance, Nb on (0001) Al 2 O 3 or NbN on (11 0) Al 2 O 3 , allows the elimination of the 30° in-plane rotation of the (0001)AlN film with respect to the (0001) or (11 0) working surface of the sapphire substrate.