电流辅助烧结Cu原子扩散激活能影响机理第一性原理计算与实验研究OA北大核心CSTPCD

The effect of the applied electric field on the diffusion activation energy of Cu crystal was studied by the first-principles calculation and current assisted sintering.The results show that the applied electric field and current reduce the difficulty of Cu vacancy generation,but the atomic migration energy is almost unchanged,resulting in a slight decrease in diffusion activation energy after reaching the electric field intensity(current density)threshold(2 V·Å‒1(307.1 A·cm‒2)),and a sharp decrease after exceeding the threshold;finally,after the electric field intensity(current density)reaching 5 V·Å‒1(708.5 A·cm‒2),the vacancy formation energy gradually decreases to 0,the diffusion activation energy drops to the critical value,and the critical value of diffusion activation energy decreases by about 60.2%compared with that of the threshold value.The diffusion activation energy shows a regular decline trend under the action of electric field or current,and the experimental results show a good positive correlation with the first-principle simulation results.