Hostname: page-component-77c89778f8-fv566 Total loading time: 0 Render date: 2024-07-22T06:56:48.719Z Has data issue: false hasContentIssue false
  • English
  • Français

An Evaluation of the Effects of Benzotriazole in NH4OH Slurry for Copper CMP

Published online by Cambridge University Press:  14 March 2011

V.S.C. Len ,
D.W. Mcneill  and
H.S. Gamble
V.S.C. Len
Affiliation:
School of Electrical & Electronic Engineering, The Queen's University of Belfast, Belfast BT9 5AH, Northern Ireland
D.W. Mcneill
Affiliation:
School of Electrical & Electronic Engineering, The Queen's University of Belfast, Belfast BT9 5AH, Northern Ireland
H.S. Gamble
Affiliation:
School of Electrical & Electronic Engineering, The Queen's University of Belfast, Belfast BT9 5AH, Northern Ireland
Get access

Abstract

Chemical mechanical polishing (CMP) of copper using alumina-based NH4OH slurry containing benzotriazole (BTA) has been evaluated in terms of polish efficiency and viability. Dishing of damascene copper patterns can result from a combination of chemical dissolution and mechanical abrasion due to the deformed polishing pad bending into the recessed copper regions. The addition of at least 0.1 wt.% BTA to the slurry leads to the formation of a thin Cu(I)-BTA polymer on the copper surface during CMP. This polymer reduces the amount of dishing by an order of magnitude. At the same time, however, the CMP polish rate falls sharply with the addition of 0.1 - 0.25 wt.% BTA to the slurry. Above 0.25 wt.% BTA, the polish rate falls no further. Stability of alumina particles in the NH4OH slurry is found to deteriorate with the addition of BTA. Integrated copper/barrier electromigration resistance test structures with large contact areas (2×2mm) have been successfully patterned using a 2-step CMP/etching process scheme, using a BTA-containing slurry to minimise dishing.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 613: Symposium E – Chemical-Mechanical Polishing 2000 - Fundamentals… , 2000 , E7.4.1
Copyright
Copyright © Materials Research Society 2000

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Steigerwald, J.M., Zirpoli, R., Murarka, S.P., Price, D., Gutmann, R.J., J. Electrochem. Soc., 141, 2842 (1994).10.1149/1.2059241Google Scholar
2. Steigerwald, J.M., Murarka, S.P., Ho, J., Gutmann, R.J., Duquette, D.J., J. Vac. Sci. Tech B, 13, 2215 (1995).10.1116/1.588106Google Scholar
3. Steigerwald, J.M., Murarka, S.P., Gutmann, R.J., Duquette, D.J., Materials Chem & Phys, 41, 217 (1995).10.1016/0254-0584(95)01516-7Google Scholar
4. Carpio, R., Farkas, J., Jairath, R., Thin Solid Films, 266, 238 (1995).10.1016/0040-6090(95)06649-7Google Scholar
5. Luo, Q., Campbell, D. R., Babu, S. V., Langmuir, 12, 3563 (1996).10.1021/la960062wGoogle Scholar
6. Luo, Q., Mackay, R. A., Babu, S. V., Chem. Material, 9, 2101 (1997).10.1021/cm970168sGoogle Scholar
7. Thomas, R.R., Brusic, V.A., Rush, B.M., J. Electrochem. Soc., 139, 678 (1992).10.1149/1.2069284Google Scholar
8. Brusic, V., Frisch, M.A., Eldridge, B.N., Novak, F.P., Kaufmann, F.B., Rush, B.M., Frankel, G.S., J. Electrochem. Soc., 138, 2253 (1991).10.1149/1.2085957Google Scholar