High-Temperature Healing of Cracklike Flaws in Titanium Ion-Implanted Sapphire |
| |
Authors: | James D Powers reas M Glaeser |
| |
Affiliation: | Department of Materials Science and Mineral Engineering, University of California, Berkeley, California 94720 |
| |
Abstract: | Controlled-geometry voids were introduced into unim-planted and Ti-implanted high-purity c -axis sapphire substrates using microfabrication techniques and ion beam etching, and subsequently transferred to an internal interface by hot-pressing. The morphological evolution of crack-like and channellike defects oriented parallel to the basal plane in response to anneals at 1700°C was studied. The healing behavior of defects in the unimplanted and Ti-ion-implanted samples differs significantly. Ti additions appear to reverse the directional dependence of the healing characteristics in undoped sapphire, greatly stabilizing defects with edges aligned along the 1100] direction, while reducing the stability of defects with edges aligned parallel to the 1120] direction relative to unimplanted sapphire. The healing characteristics of unimplanted and Ti-implanted sapphire substrates are compared and contrasted with those observed previously in Ca- and Mg-ion-implanted sapphire. |
| |
Keywords: | |
|
|