Abstract
In order to reduce specific contact resistance at via/interconnect interface and to avoid device degradation with Cu diffusion into dielectrics, via cleaning technology is a critical issue for a scaled down Cu multilevel metallization. Effects of cleaning processes are investigated for CHF 3 plasma-etched SiO 2/SiN/Cu via-structures. Effects of dilute HF (DHF) cleaning, hydrogen plasma cleaning, oxygen plasma cleaning, hexafluoroacetylacetone (H(hfac)) vapor cleaning, and vacuum anneal cleaning are investigated using an angle-resolved x-ray photoelectron spectroscopy (XPS). Cu contamination removal using dilute oxalic acid (DOA) is investigated using total reflection x-ray fluorescence analysis (TRXRF). Based on the results, we developed an optimized cleaning sequence which consists of a brief oxygen plasma exposure, DHF dipping, followed by exposure to H(hfac) vapors. The cleaning sequence is effective in obtaining a clean dielectric surface and an oxide-free Cu surface at via bottom. Direct-contacted via structures were fabricated by a dual-damascene process using the cleaning sequence. The specific contact resistance reduces to 20% of the reported values. We expect that the via resistance is low enough to be used in 0.13 μm generation and beyond.
| Original language | English |
|---|---|
| Title of host publication | Materials Research Society Symposium - Proceedings |
| Pages | 521-533 |
| Number of pages | 13 |
| Volume | 564 |
| Publication status | Published - 1999 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
Cite this
Low resistance copper via technology. / Ueno, Kazuyoshi; Donnelly, V. M.; Tsuchiya, Y.; Aoki, H.
Materials Research Society Symposium - Proceedings. Vol. 564 1999. p. 521-533.Research output: Chapter in Book/Report/Conference proceeding › Chapter
}
TY - CHAP
T1 - Low resistance copper via technology
AU - Ueno, Kazuyoshi
AU - Donnelly, V. M.
AU - Tsuchiya, Y.
AU - Aoki, H.
PY - 1999
Y1 - 1999
N2 - In order to reduce specific contact resistance at via/interconnect interface and to avoid device degradation with Cu diffusion into dielectrics, via cleaning technology is a critical issue for a scaled down Cu multilevel metallization. Effects of cleaning processes are investigated for CHF 3 plasma-etched SiO 2/SiN/Cu via-structures. Effects of dilute HF (DHF) cleaning, hydrogen plasma cleaning, oxygen plasma cleaning, hexafluoroacetylacetone (H(hfac)) vapor cleaning, and vacuum anneal cleaning are investigated using an angle-resolved x-ray photoelectron spectroscopy (XPS). Cu contamination removal using dilute oxalic acid (DOA) is investigated using total reflection x-ray fluorescence analysis (TRXRF). Based on the results, we developed an optimized cleaning sequence which consists of a brief oxygen plasma exposure, DHF dipping, followed by exposure to H(hfac) vapors. The cleaning sequence is effective in obtaining a clean dielectric surface and an oxide-free Cu surface at via bottom. Direct-contacted via structures were fabricated by a dual-damascene process using the cleaning sequence. The specific contact resistance reduces to 20% of the reported values. We expect that the via resistance is low enough to be used in 0.13 μm generation and beyond.
AB - In order to reduce specific contact resistance at via/interconnect interface and to avoid device degradation with Cu diffusion into dielectrics, via cleaning technology is a critical issue for a scaled down Cu multilevel metallization. Effects of cleaning processes are investigated for CHF 3 plasma-etched SiO 2/SiN/Cu via-structures. Effects of dilute HF (DHF) cleaning, hydrogen plasma cleaning, oxygen plasma cleaning, hexafluoroacetylacetone (H(hfac)) vapor cleaning, and vacuum anneal cleaning are investigated using an angle-resolved x-ray photoelectron spectroscopy (XPS). Cu contamination removal using dilute oxalic acid (DOA) is investigated using total reflection x-ray fluorescence analysis (TRXRF). Based on the results, we developed an optimized cleaning sequence which consists of a brief oxygen plasma exposure, DHF dipping, followed by exposure to H(hfac) vapors. The cleaning sequence is effective in obtaining a clean dielectric surface and an oxide-free Cu surface at via bottom. Direct-contacted via structures were fabricated by a dual-damascene process using the cleaning sequence. The specific contact resistance reduces to 20% of the reported values. We expect that the via resistance is low enough to be used in 0.13 μm generation and beyond.
UR - http://www.scopus.com/inward/record.url?scp=0033279705&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0033279705&partnerID=8YFLogxK
M3 - Chapter
VL - 564
SP - 521
EP - 533
BT - Materials Research Society Symposium - Proceedings
ER -