  Ferromagnetic ordering is reported in the post-annealed samples of Co doped
n-GaN formed by Co+ implantation. A maximum Curie temperature ~ 250K is
recorded for the sample with 8 atomic percent Co. Particle induced x-ray
emission-channeling study confirmed the substitutional Co in Ga lattice site.
Local atomic arrangement around magnetic impurities is also analyzed using
Raman study. A disordered model with carrier mediated coupling of localized
magnetic moments is made responsible for the observed ferromagnetic ordering.
