Defects produced in silver by kev silver ion bombardment

The nature and production mechanism of small defect clusters produced in single crystal silver films by room temperature bombardment with 5 to 50 keV silver ions along [001] at low dose levels (1010 to 1012 ions/cm2) was studied using electron microscopy. The defects were found to be of vacancy type over the entire energy range. At low energies (5 and 10 keV) most of the defects displayed the diffraction contrast typical of a radial strain field; at the higher energies a mixture of Frank loops and stacking fault tetrahedra was found. It was concluded that the defects were formed through the in situ collapse of vacancy rich regions produced by displacement cascades.