Surface characterization determined from the secondary electron emission coefficient upon ion bombardment

摘要

The ion induced electron emission yield upon Ar+ ion impact at 420 eV was measured for a stainless-steel sample that was partially covered with a 50 nm thick gold layer. The ion induced electron emission yield for the two target materials differs strongly and enables to reproduce the shape of the gold film with a spatial resolution that corresponds to the width of the ion beam, which is 240 mu m in the present case. Details in the two-dimensional map of the ion induced electron emission yield are explained by comparison with optical and scanning electron microscopy as well as with X-ray photoelectron spectroscopy measurements of the sample surface. In contrast to the sputtering efficiency, the ion induced electron emission yield does not depend on the orientation of the crystal structure.