New Molecular Collisional Interaction Effect in Low-Energy Sputtering

Author :Y. Yao, Z. Hargitai, M. Albert, R. G. Albridge, A. V. Barnes, J. M. Gilligan, B. Pratt Ferguson, G. Lüpke, V. D. Gordon, N. H. Tolk, J. C. Tully, G. Betz and W. Husinsky
Publication :Physical Review Letters
Publisher :The American Physical Society
Volume :81
Number :3
Pages :550-553
Year :1998

An unexpected pronounced enhancement is observed in sputtering yields per atom for N12
to N1 from a polycrystalline gold target. This effect is seen when the kinetic energy per projectile
atom is below 500 eV and increases as projectile energy decreases to near-threshold energies.
Enhancements for O12
over O1 begin at even lower kinetic energies below 100 eV per atom. This
new molecular interaction effect may be explained qualitatively by invoking a simple energy transfer
model which involves the vibrational frequency of the molecule and the collisional interaction time.