Catalytic effect of metal elements was observed in the growth of GaN and Mg-doped GaN micro-crystals. High quality GaN micro-crystals were synthesized by direct reaction of gallium and ammonia using a Ni-mesh catalyst. Mg-doped GaN micro-crystals were also grown by the same reaction scheme in the presence of MgCl2. The growth rate of GaN micro-crystals markedly increased in the presence of the catalyst. The average grain size of GaN microcrystals_x000D_ synthesized in the presence of Ni and Mg metals was larger than that in the absence of the metals. The characterization of the catalytically grown GaN micro-crystals using transmission electron microscopy and X-ray and/or electron diffraction pattern showed the growth of dislocation free hexagonal GaN micro-crystals. Photoluminescence (PL) and Catholuminescence (CL) measurements also showed the growth of good quality n- and p-type GaN microcrystals using Ni catalyst.

GaN Mg-doped Micro-crystal Vertical CVD Reactor Metal Catalyst

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