16 0

Investigation of the barrier properties of copper-vanadium alloys with a sub-tantalum layer on low-k dielectrics

Title
Investigation of the barrier properties of copper-vanadium alloys with a sub-tantalum layer on low-k dielectrics
Author
전형탁
Keywords
Cu interconnect; Diffusion barrier; Cu-V alloy; Ta; Low-k dielectric
Issue Date
2017-06
Publisher
ELSEVIER SCIENCE SA
Citation
JOURNAL OF ALLOYS AND COMPOUNDS, v. 722, page. 259-264
Abstract
In this study, we investigated the effects of a sub-Ta layer on the self-forming barrier process of a Cu-V alloy on low-k dielectrics. To determine how the sub-Ta layer affects the V-based self-forming barrier performance, Cu-V/low-k and Cu-V/Ta/low-k samples were compared using various analysis methods. The thickness, chemical composition, and reliability performance of the V-based interlayer with or without the sub-Ta layer were determined by transmission electron microscopy (TEM), X-ray photoemission spectroscopy (XPS), and thermal stability analysis, respectively. Although the sub-Ta layer adversely affected the decrease of the sheet resistance of the Cu alloy and the formation of a V-based interlayer, the experimental results revealed that the Cu-V/Ta/low-k samples exhibited good reliability and barrier properties, indicating that these properties for a Cu-V barrier layer can be enhanced by introducing a thin Ta sub-layer. XPS analysis showed that the sub-Ta layer affects the formation of a V oxide layer not only by blocking the diffusion of V atoms, but also due to the formation of Ta oxide. In the case of a V-based interlayer with a sub-Ta layer, both Ta2O5 and V2O5 compounds were formed on the low-k layer. Furthermore, according to the leakage current results, although the introduction of the sub-Ta layer improved the reliability and thermal stability of the self-forming barrier process, the Cu-V/Ta/low-k/Si structures demonstrated increased current densities under the 550 degrees C thermal stress condition. This indicates that the Cu-V alloy with the sub-Ta layer needs to be further investigated to improve the thermal stability. (C) 2017 Elsevier B.V. All rights reserved.
URI
https://www.sciencedirect.com/science/article/abs/pii/S0925838817320911?via%3Dihubhttp://repository.hanyang.ac.kr/handle/20.500.11754/114500
ISSN
0925-8388; 1873-4669
DOI
10.1016/j.jallcom.2017.06.103
Appears in Collections:
COLLEGE OF ENGINEERING[S](공과대학) > MATERIALS SCIENCE AND ENGINEERING(신소재공학부) > Articles
Files in This Item:
There are no files associated with this item.
Export
RIS (EndNote)
XLS (Excel)
XML


qrcode

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE