|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||2016 Technical Division Student Poster Competition
||SPG-19: Why Does Electromigration Occur? – A Combinatorial Study Using Ab Initio Calculations and Synchrotron Radiation Diffractometry
||Yu-chen Liu, Yung-si Yu, Shang-Jui Chiu, Yen-Ting Liu, Hsin-Yi Lee, Shih-kang Lin
|On-Site Speaker (Planned)
The electromigration effect has been known to be atomic diffusion due to unbalanced electrostatic and electron-wind forces exerted on metal ions. Recent theoretical studies show the empirical “electron-wind force” originates from electron perturbation under an external field. However, none of these models has coupled the electromigration effect and lattice stability. In this work, in-situ current stressing experiments with synchrotron X-ray diffractometry and ab initio calculations based on density functional theory were performed for pure Cu strips. At early stage of current stressing, unequal lattice expansions were observed along the strips; establishing a tensile strain gradient from the cathode towards the anode. Ab initio calculations indicate electron perturbation would cause lattice expansion. Therefore, electrons at the cathode possess more energy and would induce more electron perturbation. Thus, this strain energy gradient may provide the driving force for electromigration at early stage of current stressing.
||Definite: None Selected