Linear cascade regime

The sputtering yield is proportional to the number of displaced atoms. In the linear cascade regime that is appUcable for medium mass ions (such as argon), the number of displaced atoms, E (E, is proportional to the energy deposited per unit depth as a result of nuclear energy loss. The sputtering yield Y for particles incident normal to the surface can be expressed as foUows (31). 

It is useful to summarize the linear cascade theory of ion/solid interactions in the energy regime typical for surface analysis. The main ion effect is the production of the linear cascade of recoiled target atoms whose number distribution with depth depends on the ion energy, ion mass and target mass with typical values from 10 to 200A for 0.5 to 5 keV for Ar and Xe ions. 

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