Hostname: page-component-7bb8b95d7b-nptnm Total loading time: 0 Render date: 2024-09-25T23:23:37.231Z Has data issue: false hasContentIssue false
  • English
  • Français

Effects of Seeding Layers on Electroless Copper Deposition

Published online by Cambridge University Press:  10 February 2011

Kai Yu Liu ,
Man Siu Tse  and
Wang Ling Goh
Kai Yu Liu
Affiliation:
Micro-Fabrication Laboratory, Microelectronics Center, School of Electrical & Electronic Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798, ewlgoh@ntu.edu.sg
Man Siu Tse
Affiliation:
Micro-Fabrication Laboratory, Microelectronics Center, School of Electrical & Electronic Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798, ewlgoh@ntu.edu.sg
Wang Ling Goh
Affiliation:
Micro-Fabrication Laboratory, Microelectronics Center, School of Electrical & Electronic Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798, ewlgoh@ntu.edu.sg
Get access

Abstract

Copper has been actively pursued as the most promising candidate for replacing the current Al metallization for ULSI interconnection because of its higher electrical conductivity and resistance to electromigration. In this work, we present our experimental results on electroless copper deposition on various seeding layers from a formaldehyde-based solution with EDTA as a complexing agent. For electroless plating, a seeding layer is essential for the initiation of copper deposition. X-ray diffraction analysis revealed a variation in the crystallographic orientation of the electroless deposited copper with different underlying seeding layers. The seeding layer is the key factor affecting copper nucleation and grain growth. The initial nucleation behaviors of electroless copper deposition on palladium and copper seeding layers were investigated. The microstructure of electroless deposited copper blanket films was studied using both SEM and AFM, and the crystallinity was analyzed using XRD. The crystal orientation and surface texture of the electroless deposited copper films could be modified by thermal annealing in vacuum (10E-6 Torr) for 30 min at temperatures ranging from 200°C to 300°C. The ratio of crystal orientation, I(111)/I(200) increased with higher annealing temperature, indicating enhanced growth of the (111) crystal structure.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 564: Symposium N – Advanced Interconnects and Contacts , 1999 , 263
Copyright
Copyright © Materials Research Society 1999

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. Pai, P.L. and Ting, C.H., VMIC, 258 (1989).Google Scholar
2. Nakhara, S., Mak, C.Y. and Okinara, Y., J Electrochem. Soc. 140, 533 (1993).10.1149/1.2221082Google Scholar
3. Dubin, V.M., Diamand, Y.S., Zhao, B., et al, J. Electrochem.Soc., Vol. 144, 898 (1997).10.1149/1.1837505Google Scholar
4. Mallory, G.O. & Hajdu, J.B., Electroless Plating: Fundamental & Applications, (1990).Google Scholar
5. Patterson, J.C., Dheasuna, C. Ni, Barrett, J., et al, Applied Surface Science, Vol.91, 124 (1995).10.1016/0169-4332(95)00106-9Google Scholar
6. Dressick, W. J., Dulcey, C.S., et al, J Electrochem. Soc. Vol. 141, 210 (1994).10.1149/1.2054686Google Scholar
7. Darken, J., Printed Circuit World Convention 5, June 12–15, B 6, 2 (1990).Google Scholar
8. Johnson, B., Amster, R., and Vanasupa, L., J Electronic Materials, Vol. 27, 923 (1998).10.1007/s11664-998-0120-5Google Scholar