Quantitative comparison of sink efficiency of Cu–Nb, Cu–V and Cu–Ni interfaces for point defects

The efficacy of heterointerfaces as sinks for point defects in Cu was characterized using local measurements of tracer-impurity radiation-enhanced diffusion (RED). The measurements were performed as a function of irradiation temperature and Cu thickness in multilayer samples, with the results being compared to steady-state kinetic rate equations to determine sink strengths. Cu–Nb Kurdjumov–Sachs (KS) interfaces are found to be nearly ideal sinks for point defects, whereas Cu–Ni (1 1 1) heteroepitaxial interfaces are poor sinks; Cu–V KS interfaces are intermediate. Quantitative analysis of the RED data also yields the defect production efficiency for freely migrating defects in Cu, which is on the order of 1% for MeV Kr irradiation.