Helium atom scattering has been used to probe the surface damage created on GaAs(110) by Ar+ ion bombardment. The scattering cross section, Σ, of a single monovacancy is found to be ~150 Å2. The average number of defects comprising isolated impact craters, estimated from the scattering cross section per crater, is found to decrease with increasing crystal temperature during bombardment. This decrease occurs during or shortly following the bombardment event, and is different from simple thermal annealing. We propose that thermal accommodation of target adatom energy, which requires the number of adatom hops before freezing to increase with increasing crystal temperature, increases the adatom-vacancy recombination probability. Increasing the ion energy from 600 to 2400 eV does not change the cross section per single crater, but apparently impedes the probability of recombin.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Materials Chemistry