Surface Morphology of GaN Surfaces during Molecular Beam Epitaxy

Morphology and surface reconstructions of m-plane GaN

M-plane GaN(1 1 00) is grown by plasma assisted molecular beam epitaxy on ZnO(1 1 00) substrates. A low-temperature GaN buffer layer is found to be necessary to obtain good structural quality of the films. Well oriented (1 1 00) GaN films are obtained, with a slate like surface morphology. On the GaN(1 1 00) surfaces, reconstructions with symmetry of c(2x2) and approximate "4×5" are found under...

Ga Adlayer Coverage and Surface Morphology Evolution during GaN Growth by Plasma-assisted Molecular Beam Epitaxy

Ga adlayer coverage and surface morphology evolution during GaN grown by PAMBE are studied on an atomic scale. Ga adlayer coverage, which is closely dependent on the Ga/N flux ratios, is found to be a very important factor in determining the surface morphology. A laterally contracted Ga bilayer is able to stabilize the GaN surface to produce the minimum pit density. Such an energetically favora...

Gallium desorption kinetics on (0001) GaN surface during the growth of GaN by molecular-beam epitaxy

Gallium Ga surface desorption behavior was investigated using reflection high-energy electron diffraction during the GaN growth. It was found that the desorption of Ga atoms from the 0001 GaN surfaces under different III-V ratio dependents on the coverage of adsorbed atoms. Doing so led to desorption energies of 2.76 eV for Ga droplets, 1.24–1.89 eV for Ga under Ga-rich growth conditions, and 0...

Effect of Buffer Layer and Iii/v Ratio on the Surface Morphology of Gan Grown by Mbe

The surface morphology of GaN is observed by atomic force microscopy for growth on GaN and AlN buffer layers and as a function of III/V flux ratio. Films are grown on sapphire substrates by molecular beam epitaxy using a radio frequency nitrogen plasma source. Growth using GaN buffer layers leads to N-polar films, with surfaces strongly dependent on the flux conditions used. Flat surfaces can b...

Surface morphology evolution of m-plane (1(1)over-bar00) GaN during molecular beam epitaxy growth: Impact of Ga/N ratio, miscut direction, and growth temperature