The effect of zirconium implantation on the structure of sapphire

The Z-contrast images from transmission electron microscope indicated: a near surface damaged layer ∼30 nm thick, a subsurface region exhibiting “random” de-channeling ∼52 nm thick, and a deeper damaged, crystalline zone ∼64 nm thick. The RBS-C spectra confirmed the presence of these three regions. The two damaged regions contained high concentrations of as yet unresolved defect clusters. The intermediate region contained Zr-clusters embedded in an “amorphous” matrix that exhibited short-range order corresponding to γ-Al2O3, i.e., a defective spinel structure. The EELS measurements show that the amorphous region is deficient in oxygen.