Growth and structural characterization of III-N-V semiconductor alloys

The growth of GaNAs and related alloys has been studied using metal-organic molecular beam epitaxy. The lattice mismatch of GaNAs layers grown on GaAs induces lattice relaxation, the details of which are investigated with a mapping measurement of x-ray diffraction. The experimental results are compared to the calculated value of the critical thickness for the generation of misfit dislocations. It is shown that the surface morphology changes with the nitrogen (N) incorporation and, especially, wire-like surfaces associated with lateral compositional modulation are observed in a certain range of N compositions and with a thickness of more than 1 μm. The effects of indium and selenium doping on the N incorporation in GaNAs alloys are also discussed.