GaN thin film fabrication by reaction of laser evaporated Ga and GaAs in NH 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 ls532 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. q1998 Elsevier Science B.V.