Measurement of the sputter yield after mild ion erosion of a pristine Cu(001) surface

► STM is used to image the Cu(001) surface after mild 800 eV Ar+ ion bombardment. ► The observed coverage of vacancy and adatom islands varies in the temperature range of 200-350 K. ► This provides an apparent temperature dependent sputter yield that has to be corrected for the STM tip size. ► The difference in apparent sputter yield for low and high temperature is attributed to the annihilation of bulk defects. ► For the pristine Cu(001) a sputter yield of 1.2 atom/ion is determined.