Ion implantation and annealing of crystalline oxides and ceramic materials

The response of several crystalline oxides or ceramic materials to ion implantation and subsequent thermal annealing is described. For both SrTiO3 and CaTiO3 single crystals, the near-surface region can be turned amorphous by relatively low doses of heavy ions (Pb, 1015/cm2, 540 keV). During annealing, the amorphous region recrystallizes epitaxially with the underlying substrate by simple solid-phase epitaxy, and the crystallization kinetics have been determined for both of these materials. In Al2O3, the amorphous phase of the pure material is produced by a stoichiometric implant at liquid nitrogen temperature. During annealing, the amorphous film crystallizes in the (crystalline) γ phase, followed by the transformation of the γ to the α phase at a well-defined interface. The kinetics characterizing the growth of α-Al2O3 have been determined. Preliminary results are presented on the effect of impurities (Fe) on the nature and kinetics of the crystallization of amorphous Al2O3. (orig.)