Volume expansion and annealing compaction of ion-bombarded single-crystal and polycrystalline α-Al2O3

Abstract
Radiation damage of α‐Al2O3 was systematically investigated as a function of incident ion mass and energy partitioning into atomic and electronic processes by measuring the resulting stress in the ion‐bombarded layer with a cantilever beam technique. Heavy‐ion‐bombardment‐induced expansion in the implanted surface layer shows strong anisotropy which appears to be related to the higher defect production rate along the c axis. Stress relief is observed at fluences above 1×1015 Ar/cm2 for the [0001] orientation only and is attributed to basal slip. Hydrogen bombardment subsequent to heavy‐ion bombardment results in compaction which is also anisotropic. The anisotropy of both the expansion and the compaction point to structure sensitive defects. Approximately 80% of the radiation damage is annealed at 900 °C for the [0001] orientation and 60% for the [011̄0] orientation. A similar expansion‐compaction response is found in argon‐ and hydrogen‐bombarded polycrystalline Al2O3.

This publication has 13 references indexed in Scilit: