Microstructure of the near-surface layers of ion-implanted polycrystalline Cu

Abstract

Investigation of the submicrostructure formed in the near surface layers of ion implanted polycrystalline Cu was carried out using transmission electron microscopy. Ni and Hf ions were implanted in the pulsed-periodical regime at an accelerating voltage of 40 kV. Irradiation doses were equal to 1 × 10 17 ion cm -2 for Hf and 2.0 × 10 17 and 4.6 × 10 17 ion cm -2 for Ni. It has bees established that a developed dislocation submicrostructure was formed in Cu under ion implantation. The near-surface layers with the induced submicrostructure exceeded 100 μm. The dislocation density in the indicated layer increases approximately 15–40 times as compared with that in the initial state for recrystallization Cu and 20%–30% for work-hardened Cu. With increase in ion flux from 0.09 × 10 14 to 0.35 × 10 14 ion cm -2 s -1 the maximum dislocation density increases; further ion flux does not result in the dislocation density growth. The change in the temperature of irradiated Cu (343–523 K) does not result in the change of a dislocation structure character in the target near-surface layer.