Tuning the shape and damage in ion-beam induced ripples on silicon

We investigate the influence of ion beam parameters on the ripple formation on Si(001) surfaces after bombardment with Xe+ ions of 25 keV kinetic energy using a scanning ion beam system. By combining grazing incidence x-ray diffraction, small angle scattering and x-ray reflectivity, we show that during ion irradiation with 70◦ off-normal angle of incidence, changing the size of the irradiated area leads to an increased number of defects at the interface towards crystalline material. At 65◦ angle of incidence, the ripple amplitude grows.