The depth of sputtering damage in tungsten by field-ion microscopy

The field-ion microscope has been used to investigate the depth of the structural damage caused to tungsten by low-energy ion bombardment. The bombardment geometry was such that the ions were incident in a direction parallel to the specimen axis, ⟨011⟩, so that subsequent field evaporation directly revealed the depth of point defect damage. The results show that the depth of damage is greater for argon ions than for xenon ions and within the energy and dose ranges used (1–3keV; 1015–1017 ions cm2), the depth of damage varies between 2 nm and Ilnm. These results are presented together with previously obtained data at lower energies (0–1 keV) and compared with theoretical predictions obtained using the E-DEP-I computer code of Manning and Muller.