Surface Structure and Morphology of Gallium Nitride Thin Film Grown on Molybdenum Disulfide Layer by Molecular Beam Epitaxy

The layer of gallium nitride thin film was grown near to the surface of the molybdenum disulfide substrate by plasma-assisted molecule beam epitaxy (PA-MBE) system. In-situ RHEED and ex-situ characterization of AFM and SEM were used to exploit subsequently the surface character of GaN films. The results show that the RHEED pattern demonstrated the mix structure of polycrystalline and amorphous with 2dimensional (2D) growth mode. The crystalline structure was influenced by the defect constructed in the GaN films. Meanwhile, the 3D AFM image served in detail the smooth surface with root mean square (RMS) of 3.87 nm. Further, the SEM image with an EDS pattern performed the fixture of morphology and surface composition. However, Ga cluster like particles presented on the surface of the GaN layer. The sufficient of the thermal energy with the crystalline structure provided by the substrate would be a promising approach for creating GaN film with greater structures and smoother surface.