The formation and migration energies of vacancies in quenched copper

Abstract

High-quality copper single crystals have been quenched from temperatures between 750 and 1050 degrees C. The analysis of the quenched-in resistivities gives a vacancy formation energy of (1.27+or-0.05) eV in good agreement with the monovacancy formation energy of (1.29+or-0.02) eV found by positron annihilation. Isochronal annealing of quenched copper shows two recovery stages, one centred at 0 degrees C and one above 200 degrees C. In the first stage, nearly 35% of the quenched-in resistivity is annealed out. Vacancies migrate in this stage with an activation energy of (0.74+or-0.08) eV. The sum of the measured vacancy formation and migration energies is (2.01+or-0.13) eV and agrees well with the monovacancy self-diffusion energy Q_SD^1V=(2.06+or-0.05). The data can be explained within the vacancy annealing model for stage III in electron-irradiated copper as elaborated by Schilling and co-workers (1973 and 1976).