Nanometer-size dispersions of iron in sapphire prepared by ion implantation and annealing

Some of the metal ions implanted into sapphire (single crystal α-Al2O3) are often present as metallic colloids or dispersions. Nano-composites consisting of iron particles in sapphire were prepared by implantation of 160 keV 56Fe at room temperature. The colloids were coarsened by annealing in the temperature range of 973–1673 K in a reducing atmosphere. Rutherford backscattering-ion channeling (RBS-C) and transmission electron microscopy (TEM) were used to determine the lattice damage as well as the nature, size and distribution of the iron. A range of particle sizes and shapes can be obtained by choice of implantation and/or annealing parameters.