GaN thin film fabrication by reaction of laser evaporated Ga and GaAs in NH3 atmosphere

The III group element nitrides (AlN, GaN, InN) have been prepared by laser ablation of the metals and simultaneous exposure to NH3. This study reports the growth of polycrystalline thin films of GaN on Si(100) by Nd:YAG (?=532 nm) laser evaporation of bare Ga and GaAs in a NH3 atmosphere. The key problems are the gas phase solvation mechanism leading to Ga(NH3)n cluster formation and to direct nitridation of the target to yield GaN. Time of flight mass spectrometry has been used to monitor ablation plume components. The films were analyzed by conventional techniques, such as X-ray diffraction (XRD), scanning electron microscopy (SEM) and IR spectroscopy.