Low-energy Ar+ ion bombardment-induced modification of surface atomic bond lengths on InP(100) wafer

We report the first direct measurement of surface interatomic bond distance modifications due to ion bombardment. The experiments were performed using low energy Ar+ ion on a InP(100) surface by photoemission x-ray absorption fine structure. The structural changes are sputtering time dependent and result in first (P–In) and second (P–P) surface bond distances relaxation approaching the bulk values. It suggests that, prior to bond breaking, the Ar+ ion beam first stretches atomic bond lengths during a precursor stage, with small energy and momentum transfer. This work brings new insights into the knowledge of ion sputtering various micromechanisms which is relevant for surface preparation.