Beam induced decomposition and sputtering of LiI

Abstract

Energy distributions of atoms and molecules sputtered with 6 keV Ne⁺, Ar⁺, Kr⁺ and Xe⁺ beams have been measured at various temperatures of a LiI target. It was found that two processes contribute simultaneously to the sputtering of LiI. These are: (a) the collision cascade mechanism leading to a flux of sputtered particles Φ_coll(E) ∼ E/(E + Eb)³, where E _b is the surface binding energy, and (b) thermal evaporation of beam-decomposed material with a Maxwellian flux Φ_th(E) ∼ E exp(-E/kT). The last mechanism has been studied in more detail by varying the target temperature, the projectile and the ion current density. A comparison of the obtained results with previous experimental data as well as with sputtering theories is presented.