Ge Surface Displacements Due to Low Energy Particles

Abstract

AbstractThe production of surface defects by low energy 4He and Xe ions incident on very smooth Ge(001)2x1 surfaces is reported. Roughening at -50°C by 100-500 eV ions is measured by RHEED in real-time using the intensity of the out-of-phase specular beam. For He, the surface displacements per ion range from 0.05 to 0.3 and are comparable to our binary collision calculated surface vacancy production rate for a displacement threshold energy of 11 eV (3/4 of bulk value). For Xe, the displacement rate ranges from 2 to 10 (∼30x higher) and falls between the calculated total vacancy and total defect (vacancy + interstitial) production rates.