Share Email Print

Proceedings Paper

Dependence of EM performance on linewidth for Cu dual-inlaid structures
Author(s): Larry Zhao; Cristiano Capasso; Amit P. Marathe; Stacye R. Thrasher; Richard Hernandez; Peggy Mulski; Stewart Rose; Timothy Nguyen; Martin Gall; Hisao Kawasaki
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

EM is a diffusion phenomenon under the influence of driving forces. The major diffusion paths for Cu dual inlaid structures are believed to be interfaces and grain boundaries. Cu dual inlaid structures usually have a refractory metal barrier layer and are capped with a dielectric layer. The fastest diffusion path in such a structure is believed to be the Cu-dielectric interface. We studied the relationship between EM behavior and metal line- width for two types of EM test structures. It was found that the median time to failure (MTTF) increased significantly as the metal line-width increased for each type of structures when tested under the same current density. In one case, the MTTF increased by 200 percent as the metal line-width was doubled. Microstructure analysis on the metal lines showed that the wider lines had almost a bamboo structure while the narrower lines consisted of small grains. Therefore, the dramatic decrease in MTTF in the narrower line structure was most likely due to a significant increase in grain boundary diffusion. Mathematical treatment has been performed on the experimental data based on the assumption that the MTTF is reciprocally proportional to the drift velocity or the diffusivity, in this case, of Cu. It has been concluded that grain boundaries can be the fastest diffusion path in Cu dual inlaid structures when the grain size is small.

Paper Details

Date Published: 23 October 2000
PDF: 8 pages
Proc. SPIE 4229, Microelectronic Yield, Reliability, and Advanced Packaging, (23 October 2000); doi: 10.1117/12.404883
Show Author Affiliations
Larry Zhao, Advanced Micro Devices, Inc. (United States)
Cristiano Capasso, Motorola (United States)
Amit P. Marathe, Advanced Micro Devices, Inc. (United States)
Stacye R. Thrasher, Motorola (United States)
Richard Hernandez, Motorola (United States)
Peggy Mulski, Motorola (United States)
Stewart Rose, Motorola (United States)
Timothy Nguyen, Motorola (United States)
Martin Gall, Motorola (United States)
Hisao Kawasaki, Motorola (United States)

Published in SPIE Proceedings Vol. 4229:
Microelectronic Yield, Reliability, and Advanced Packaging
Cher Ming Tan; Yeng-Kaung Peng; Mali Mahalingam; Krishnamachar Prasad, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?