NOTE ON THE FORMATION OF SURFACE CARBIDES

Features of the effect of ion bombardment and its influence on the composition of solid surfaces are considered. During ion bombardment, not only does cleaning (sputtering) of the surface take place, but the formation of carbides through the implantation of carbon from contamination also occurs. Such species were recognized clearly from their chemical shifts of XPS on intermetallic compounds, namely LaNi5, CaNi5, TiFe, MgaNi and Mg2Cu and on the hydride Mg2NiH4. These surface carbides, for example, can seriously restrict data analysis owing to their contribution to the core level alterations, and the rate of sputtering owing to their extreme hardness. However, ion bombardment would serve as an unusual method of preparation of some compounds which cannot be obtained by conventional means. Types of problems, methods and results of their investigation are described. © 1990.