Hostname: page-component-78c5997874-g7gxr Total loading time: 0 Render date: 2024-11-10T10:33:23.430Z Has data issue: false hasContentIssue false

Investigation on Abrasive Free Copper Chemical Mechanical Planarization for Cu/low k and Cu/ultra low k interconnects

Published online by Cambridge University Press:  01 February 2011

S. Balakumar
Affiliation:
Institute of Microelectronics, 11, Science Park Road, Science Park II, Singapore117685
T. Haque
Affiliation:
Institute of Microelectronics, 11, Science Park Road, Science Park II, Singapore117685 Dept of Mechanical Engineering, National University of Singapore, Singapore
R. Kumar
Affiliation:
Institute of Microelectronics, 11, Science Park Road, Science Park II, Singapore117685
A.S. Kumar
Affiliation:
Dept of Mechanical Engineering, National University of Singapore, Singapore
M. Rahman
Affiliation:
Dept of Mechanical Engineering, National University of Singapore, Singapore
Get access

Abstract

Abrasive Free Copper Chemical Mechanical Polishing (AF-CMP) was developed for Cu/low k materials. Blanket film Cu removal rate of 6000 Å/min with very less non-uniformity of 3% achieved for polishing pressure of 1.5 psi. CMP process window and lower critical pressure were identified with pattern wafers. Material removal mechanism was studied using surface morphology of Copper blanket wafers polished using different pressure, rotation rate and slurry flow rate. Material Removal Mechanism (wear mechanism) such as Chemical wear (etching) and mechanical wear (fatigue wear, particle adhesion wear and abrasion wear) have been found. The increase of slurry flow rate and relative velocity and the decrease of pressure give the dominance of chemical wear in material removal mechanism, and vice versa. Dishing control was achieved during Cu polish using different carrier/platen speed for Cu/SiLKTM patterned wafers. The cumulative distribution of the metal line-to-line leakage current measurements of wafers shows good performance and it is comparable to abrasive process.

Type
Research Article
Copyright
Copyright © Materials Research Society 2005

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

[1] S, Balakumar., Chen, X. T., Chen, Y. W., Selvaraj, T., Lin, B. F., Kumar, R., Hara, T., Fujimoto, M. and Shimura, Y., Peeling and delamination in Cu/SiLKTM process during Cu-CMP, Thin Solid Films, Vol. 462-463, pp. 161167, 2004 Google Scholar
[2] Bajaj, R., Zutshi, A., Surana, R., N, Naik, and Pan, T., Integration Challenges for CMP of Copper, MRS Bullettin, Oct 2002, P776 Google Scholar
[3] Li, Hugh, VanHaneham, Matt, Quanchi, John, “Slurry Development for Cu/ultra low k CMPMat. Res. Soc. Symp. Proc, Vol.767 page F5.3.1. Google Scholar
[4] Kondo, S., Sakuma, N., Homma, Y., Goto, Y., Ohashi, N., Yamaguchi, H. and Owada, N., Abrasive-Free Polishing for Copper Damascene Interconnection. Journal of The Electrochemical Society, Vol. 147(10), pp. 39073913, 2000 Google Scholar
[5] Steigerwald, J.M., Murarka, S.P., Gutmann, R.J. and Duquette, D.J., Chemical Processes in the Chemical Mechanical Polishing of Copper. Materials Chemistry and Physics, Vol. 41, pp.217228, 1995 Google Scholar
[6] Hernandez, J., Wrschka, P. and Oehrlein, G.S., Surface Chemistry Studies of Copper CMP. Journal of the Electrochemical Society, Vol. 148 (7), pp. G389–G397, 2001 Google Scholar
[7] Fischer, T.E., Anderson, M.P., Jahanmir, S. and Salher, R., Friction and wear of tough and brittle Zirconia in nitrogen, air, water, hexadecane and hexadecane containing stearic acid Wear, Vol. 124 (2), pp.133148, 1988 Google Scholar
[8] Rabinowicz, E., Friction and Wear of Materials, 2nd Ed., John Wiley and Sons, Inc., 1995 Google Scholar
[9] Shan, L., Zhou, C., Danyluk, S., IEE Transactions on Semiconductor Manufacturing, Vol. 14(3), p. 207211, 2001 Google Scholar
[10] Archard, J.F., Journal of Applied Physics, 24, 981 (1953).Google Scholar
[11] Haque, T, Balakumar, S., Kumar, A.S. and Rahman, M., A Material Removal Rate Model for Copper Abrasive-free Chemical Mechanical Planarization, Journal of the Electrochemical Society (Accepted)Google Scholar
[12] Balakumar, S. Tsang, Chi Fo, N, Matsuki., CMP process development and post-CMP defects studies on Cu/ultra low k materials with single damascene scheme”, Advanced Metallization Conference 2003 (AMC 2003), 2004, Pages 613620 Google Scholar
[13] Denardis, D. Sorooshian, Habiro, M., Philipossian, C., Jpn. J Appl. Phys., 42, 609, (2003)Google Scholar