Catalytic growth of high quality GaN micro-crystals

GaN micro-crystals were catalytically grown using Ni-mesh in direct reactio n of gallium and ammonia. At 1100 degreesC, the growth rate of the GaN crys tals 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 G aN crystal size. The structural characterization of the GaN crystal showed the growth of dislocation free hexagonal GaN single crystal. PL spectrum sh owed a strong band edge emission at the energy position of similar to3.35eV with FWHM of similar to 115meV. The time-resolved photoluminescence measur ements also revealed the growth of high quality GaN micro-crystal grains. T he catalytic activity for the growth of the GaN crystals was discussed base d on the in situ analyzed gas composition during the growth. (C) 2002 Elsev ier Science B.V. All rights reserved.