Production Of SiO_n~- And (SiO_2)_n~-, n= 2, 3, 4 Molecular And Cluster Anion Beams From A Cesium-Sputter-Type Negative Ion Source

摘要

Theoretical models have been developed for many decades to describe the sputtering process. These models have used various explanations to account for the mechanisms that lead to secondary ion beam production via sputtering from solid surfaces. Experimental studies of negative ion beam production, although dependent on source design and geometry, reveal trends which can, in turn, assist theorists in identifying the important microscopic events involved in sputtering. The study described in this report characterizes the yields of SiO_n~- and (SiO_2)_n~-, n= 2, 3, 4 molecules and clusters from a cylindrical-geometry, cesium-sputter-type negative ion source. Mass- and chargedanalyzed beam currents ranging from several picoamperes to several nanoamperes were observed.