The removal efficiency and the relative removal efficiency between two different materials with three performance factors

normal removal rate

volume removal rate and sputtering yield are analyzed in the ion beam figuring process. With the Sigmund sputtering theory

build up are the relation models between these three factors and the processing parameters

such as ion energy

ion flux and ion incident angle. Experiments with samples of Zerodur

SiO2 and K4 are made to analyze these relations. The experimental results verify the theoretical models. The models and experimental results indicate that the removal rate increases with ion current linearly and is about proportional to the square root of the ion energy. The removal rate increases with incident angle and climbes the summit at about 60~80°; the relative removal efficiency is independent of ion flux; the energy effect of the relative removal efficiency can be ignored and the angle effect is rather obvious.