Temperature behaviour of strain and defects in sapphire implanted with Si+ ions

Strain and defects produced by implantation of Si+ ions into r-plane sapphire are studied by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Post-implantation annealing carried out at temperatures up to 1100 °C is observed to reduce strain and the number of defects. The peak value of strain falls linearly with increasing annealing temperature. Peaks in the strain depth profiles correspond to the regions of highest defect density. Roughness and amorphous content at the surface can be reduced by high temperature annealing.