Growth of AlGaN:Si Heterostructures with Bragg Reflectors for the Blue-Green Spectral Range

The paper presents the results of calculation and growth of AlGaN/AlN heteroepitaxial structures with Bragg reflectors for the blue-green spectral range corresponding to the maximum broadband luminescence of AlGaN:Si layers grown by molecular beam epitaxy from ammonia. Structures with an active AlGaN: Si region located on one lower Bragg reflector for a wavelength of 510 nm and between two Bragg reflectors for a wavelength of 510 nm were grown. For both heteroepitaxial structures, selection of the emission of the active layer in the given spectral range by the lower Bragg reflectors was demonstrated. It is shown that large total thickness of the heterostructure with two Bragg reflectors leads to the formation of cracks and macroscopic defects on the surface of the heteroepitaxial structure.