| Summary: | The inert gas ion bombardment of solid surfaces has
found many uses in the field of analytical chemistry. In
one method of spectrochemical analysis, inert gas ion
bombardment in a glow discharge is used to produce an atomic
vapor, representative of the sample bulk, which is analyzed
using atomic absorption techniques. Gas jets directed at
the sample surface during the discharge increase the removal
rate of sample material from the surface. Such bombardment
of solid surfaces results in changes to the surface which
are visually evident in the formation of craters and surface
deposits. This thesis was designed to gain a better
understanding of the changes in a brass surface caused by
jet-enhanced sputtering. Electron spectroscopy for chemical
analysis (ESCA) is used to study selected regions of the
surface. Changes in chemical composition were observed as
successive atomic layers were removed from the sample.
The results of this investigation indicate that the
effects of ion bombardment can be explained in terms of the
selective sputtering of one bulk component over another.
The surfaces of the sputtered craters were found to be
depleted of the higher sputtering yield component, Zn, when
compared to the bulk composition. In a deposit, the
component with the highest sputtering yield was found to be
more concentrated in layers closest to the bulk material.
The component with the lowest sputtering yield was found at
relatively higher concentrations nearest the deposit
surface. The component with the higher sputtering yield is
selectively sputtered first during the glow discharge, and
consequently is deposited with a higher concentration
closest to the bulk, the converse being true for the lowest
sputtering yield component. === Graduation date: 1993
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