Study of the sputtering and secondary ion emission of binary Fe-based alloys

The sputtering and secondary ion emission of binary Fe-based alloys with simple phase diagrams have been studied simultaneously. A series of FeNi and FeCr alloys in the concentration range 0-100% has been bombarded with 4keV Kr+ ions in a secondary ion mass spectrometer. The composition of the secondary ions has been analyzed, and a fraction of the sputtered material has also been collected and analyzed using electron microprobe. The surface topography of the etched samples has been also studied with a scanning electron microscope. The relative sputtering coefficients of the metals were determined, and the preferential sputtering of the alloying component of lower S was proved. An increase in sputtering yield was observed in the vicinity of composition of the melting point (i.e. binding energy) minimum; the degree of secondary ionization is different in this narrow concentration range. The connection existing between the physico-chemical properties of alloys and their secondary emission process is such emphasized