PHASE-FORMATION AFTER HIGH FLUENCE IMPLANTATION OF FE IN ALN - A MOSSBAUER STUDY

To study the chemical bonds which can be formed by ion implantation of metals in a ceramic matrix, we have performed Mossbauer spectroscopy with Fe-57 in implanted and post-annealed AlN samples at Fe concentrat ions from 10 at% to 40 at%. Characterization of the Fe local environme nt led to the following results: part of Fe is surrounded by N and the rest is in the form of Fe clusters, the relative amount of Fe in each phase depending on both implanted concentration and post-annealing tr eatment. Formation of the observed nitride phase can be interpreted by substitution of Al atoms by Fe ions which leads to a FeN stoichiometr y. These results are analyzed in relationship with the formation entha lpies of the different phases.