Abstrakt
Glass (SiO2) is sputtered not only by ion impact, but the sputtering yield can be enhanced by electron impact as well. In the case of small silicate dust grains in the space environment, such eects can in uence the lifetime of the grains.
Moreover, there is a suggestion that electric eld could further enhance the sputtering yield from charged non-conducting grains. To reveal these eects, we performed experiments with a single dust grain levitated in an electrodynamic quadrupole trap.
As a representative of silicate-type space dust, we used spherical SiO2 grains with diameters around 1 micron. The grain in the trap was bombarded by 2-keV Ar+ ions and 1-keV electrons.
The sputtering yield of the ion-only bombardment (i.e., at a high surface eld) was 1.4 SiO2/ion, in the case of a combined ion and electron bombardment, the yield was 1.5 SiO2/ion, i.e., slightly higher.