For a particular plasma etch process in which the linear etch model is applicable, a degree of anisotropy of 0.8 or better is desired.
If the unobstructed ionic flux on a flat surface is 1 X 1016 atoms cm-2 sec-1 (with Ki equal to 1), what unobstructed chemical flux would result in an anisotropy of 0.8? For this process Sc is 0.0i and Kf is 0.1.