skip to main content

SciTech ConnectSciTech Connect

Title: In-situ scanning electron microscope observation of electromigration-induced void growth in 30 nm ½ pitch Cu interconnect structures

In-situ electromigration tests have been performed inside a scanning electron microscope on 30 nm wide single damascene interconnects without vias, where a good resolution was obtained and drift velocities during void growth could be measured at 300 °C. These tests showed direct evidence that the cathode end of the line, where a polycrystalline grain cluster encounters a bigger grain, can act as a flux divergent point of Cu diffusion. Moreover, it was found that a thicker barrier suppresses barrier/interface diffusivity of Cu atoms, thereby slowing down electromigration-induced void growth. It was also demonstrated that Cobalt based metal caps are beneficial to electromigration for advanced interconnects where thinner barriers are required.
Authors:
; ; ; ; ; ;  [1] ;  [2]
  1. imec, Kapeldreef 75, 3001 Leuven (Belgium)
  2. Fujitsu Semiconductor Limited, 50 Fuchigami, Akiruno, Tokyo 197-0833 (Japan)
Publication Date:
OSTI Identifier:
22278039
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 115; Journal Issue: 7; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 77 NANOSCIENCE AND NANOTECHNOLOGY; ATOMS; COBALT; COPPER; ELECTROPHORESIS; GRAIN SIZE; INTERFACES; NANOSTRUCTURES; POLYCRYSTALS; SCANNING ELECTRON MICROSCOPY; VOIDS