|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Phase Stability, Phase Transformations, and Reactive Phase Formation in Electronic Materials XV
||A New Insight on the Electromigration Effect: Strain-induced Atomic Migration under Current Stressing
||Yu-chen Liu, Yong-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 stripes. At early stage of current stressing, unequal lattice expansions were observed along the stripes; 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, a strain gradient exists and this strain energy gradient may be the driving force for electromigration at early stage of current stressing.
||Planned: A print-only volume