Catalytic growth of high quality GaN micro-crystals

Abstract

GaN micro-crystals were catalytically grown using Ni-mesh in direct reaction of gallium and ammonia. At 1100°C, the growth rate of the GaN crystals in the presence of Ni catalyst was almost ten times higher than in the absence of the catalyst. The use of the catalyst induced the increase of GaN crystal size. The structural characterization of the GaN crystal showed the growth of dislocation free hexagonal GaN single crystal. PL spectrum showed a strong band edge emission at the energy position of ∼3.35 eV with FWHM of ∼115 meV. The time-resolved photoluminescence measurements also revealed the growth of high quality GaN micro-crystal grains. The catalytic activity for the growth of the GaN crystals was discussed based on the in situ analyzed gas composition during the growth.