Strongly enhanced secondary ion emission is observed by irradiation of mole
cular ion, SF5+. It is well known that the sputter yield increases signific
antly when the solid surface is irradiated by ions at an extremely high flu
x, such as in the order of mA/cm(2). In the present study, 4keV SF5+ ions i
rradiate a beryllium surface at relatively low flux, 1 muA/cm(2). The Xe+ a
nd Ar+ monatomic ions also irradiate at the same condition for comparison.
The emitted beryllium and beryllium cluster ions are observed. The ordering
of the secondary ion intensities (1) of monatomic Be+ is I(SF5+) > I(Xe+)
> I(Ar+). For the SF5+ irradiation, formation of the cluster ions (Be-3(+),
Be-6(+)) is also observed. The irradiating molecular ions strongly affect
the surface atom emission, since a high-density collision cascade can be fo
rmed in the irradiated local area by atoms dissociated from molecular ions.
The enhanced cluster formation is also observed by the molecular ion irrad