Abstract
Copper interconnect metallizations in next generation integrated circuits will require thin diffusion barrier layers (< 20 nm) between the Cu and low-k dielectric which may also function as seed layers for subsequent material depositions. One possible structure entails a multicomponent diffusion barrier with a lower resistivity component, such as W on WNx. In this study, sputtered WNx/W bilayer thin films were investigated as diffusion barriers between Si and Cu. The total thickness of the WNx/W bilayer was fixed at 20 nm while the WNx thickness was varied from 0 to 20 nm. After deposition of the barrier films, a 100 nm thick Cu film was sputtered over the top of the ct-W and amorphous WNx bilayer. The as-deposited WNx/W film stress was found to be strongly dependent on the relative amount of WNx and W present and the addition of a Cu overlayer was found to mitigate the stress levels. The WNx/W barriers remained stable after 650°C anneals and exhibited phase transformations to W 2N. Microstructural characterization using transmission electron microscopy and x-ray diffraction and chemical analysis by x-ray photoelectron spectroscopy of the films were used to identify the as deposited and transformed phases. © 2001 Materials Research Society.
Recommended Citation
K. D. Leedy et al., "Properties of Sputtered Bilayer WNx/W Diffusion Barriers between Si and Cu," Materials Research Society Symposium Proceedings, vol. 714, pp. 1 - 6, Springer, Jan 2001.
The definitive version is available at https://doi.org/10.1557/proc-714-l4.6.1
Department(s)
Materials Science and Engineering
International Standard Book Number (ISBN)
978-155899650-2
International Standard Serial Number (ISSN)
0272-9172
Document Type
Article - Conference proceedings
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2024 Springer, All rights reserved.
Publication Date
01 Jan 2001
