Nanocluster formation in fe implanted GaN

The formation of Fe clusters in wurtzite GaN implanted with 200 keV Fe-57 ions at 350 degrees C was investigated. Cluster sizes from few nanometers up to several 100 nm depending on ion fluence, implantation, and annealing temperature have been observed for ion fluences between 4 x 10(16) and 1.6 x 10(17) cm(-2). A clear epitaxial relation between Fe and GaN was determined. X-ray diffraction, conversion electron Mossbauer spectroscopy, transmission electron microscopy, and Auger electron spectroscopy were used for the characterization of the implanted samples. Mossbauer spectroscopy shows that precipitation of Fe occurs already during implantation. (c) 2006 American Institute of Physics.