標題: In-situ TEM Study of Electromigration in Cu lines
作者: Liao, C. N.
Chen, K. C.
Wu, W. W.
Chen, L. J.
Tu, K. N.
材料科學與工程學系
Department of Materials Science and Engineering
關鍵字: Electromigration;interconnects;diffusion;twin
公開日期: 2009
摘要: The density of electric current passing through interconnecting wires in integrated circuits (IC) is increasing with continuous miniaturization of IC. Under a high operating temperature and large electric current density, some voids and hillocks may form in the interconnecting wires due to electromigration (EM), leading to device failures eventually. In this study atomic-scale EM in unpassivated copper lines has been investigated in ultrahigh vacuum by in situ transmission electron microscopy (TEM). The EM-induced atomic surface diffusion was found to be crystal-orientation dependent and occurred preferentially on the {111} planes along < 110 > directions. The high-resolution TEM images and the electron diffraction patterns of a (111)-oriented Cu grain in the Cu line revealed an EM-induced step structure at surface. Moreover, the triple point where a twin boundary meets a grain boundary was found to slow down atomic EM at grain boundaries because of the incubation time of nucleation of a new step at the triple point. The long incubation time slows down the overall rate of atomic transport. The results suggest that the EM reliability of Cu interconnects may be enhanced by forming a high density of nanometer scaled twins in the coarse-grain Cu wires.
URI: http://hdl.handle.net/11536/135019
ISBN: 978-0-7354-0680-3
ISSN: 0094-243X
期刊: STRESS-INDUCED PHENOMENA IN METALLIZATION
Volume: 1143
起始頁: 12
結束頁: +
顯示於類別:會議論文