Hostname: page-component-8448b6f56d-qsmjn Total loading time: 0 Render date: 2024-04-18T07:39:06.809Z Has data issue: false hasContentIssue false
  • English
  • Français

Effects of Electronics Assembly Processes on Benzotriazoletreated Printed Wiring Board Copper Surfaces.

Published online by Cambridge University Press:  15 February 2011

Howard E. Evans ,
Julian P. Partridge ,
Allen G. Miller  and
Marc W. Jackson
Howard E. Evans
Affiliation:
IBM Corporation, Technology Products Division, Austin, TX
Julian P. Partridge
Affiliation:
IBM Corporation, Technology Products Division, Austin, TX
Allen G. Miller
Affiliation:
IBM Application Business Systems, Rochester, MN
Marc W. Jackson
Affiliation:
IBM Application Solutions, Houston, TX.
Get access

Abstract

The performance and reliability of personal computers, workstations and other electronic products depend on the effective soldering of electronic components to printed wiring oards (PWBs). The copper surfaces of PWBs are frequently treated with benzotriazole (or similar organic complexes) to preserve solderability by preventing copper oxide formation. However, new assembly process techniques and more complex processes may degrade protective organo-copper surface complexes and allow copper oxidation to occur, thus inhibiting subsequent solder operations. This study uses Auger electron spectroscopy (AES) in conjunction with meniscograph wettability results to determine the effects of processing conditions on the solderability of PWB surfaces. Effects are characterized for aging up to 19 months; Infrared (IR) reflow in air and nitrogen; cleaning; and temperature cycles associated with adhesive or encapsulant cure. Surface compositions, oxide thicknesses, and solderability measurements are correlated to the above process steps. For example, IR reflow in air increases oxide thickness from ∼10 Å to ∼150Å (relative to sputtering rates in Ta2O5 with an attendant increase in the meniscograph time-to-neutral-buoyancy from <2 seconds to >10 seconds, relative to unprocessed PWBs. Such fundamental information serves as an invaluable complement to standard phenomenological observations of defective solder joints, and can aid in guiding processing decisions for improved yield and reliability.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 264: Symposium G – Electronic Packaging Materials Science VI , 1992 , 291
Copyright
Copyright © Materials Research Society 1992

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. Manko, H., Solders and Soldering, 325, McGraw Hill Book Co., New York, N.Y. (1979).Google Scholar
2. Wassink, R. J., Soldering in Electronics, Electrochemical Publications Limited, London (1984).Google Scholar
3. Eliott, D. H., Electronic Packaging and Prod., 81 (1986).Google Scholar
4. Cotton, J. B. and Scholles, I. R., British Corrosion Journal 2, 1 (1967).CrossRefGoogle Scholar
5. Cotton, J. B., 2nd Int. Congress Metal. Corr., New York, N.Y., 190 (1963).Google Scholar
6. Viswanadham, P., Evans, H. E. and O'Hara, J. P., Proc. SMT Conf., Atlantic City, N.J., 149 (1990).Google Scholar
7. Poling, W., Corrosion Science 10, 359 (1970).CrossRefGoogle Scholar
8. Walker, R., Metal Finishing, 64 (1973).Google Scholar
9. Brusic, V., Frisch, M.A., Eldridge, B.N., Novak, F.P., Kaufman, F.P., Rush, B.M., and Frankel, G.S., J. Electrochem. Soc. 138 (8), 2253–2259 (1991).CrossRefGoogle Scholar
10. Casullo, F.J. and Galasco, S. A., Circuits Manuf., 30 (2), 72–76 (1990).Google Scholar
11. Manara, A. and Sirtori, V., Surf. Interf. Anal. (15) 457–462 (1990).CrossRefGoogle Scholar
12. Brundle, C.R., Auerbach, D.J. and Miller, D.C., Int. SAMPE Symp. Santa Clara, Ca, 236–242 (1987).Google Scholar
13. Boyer, A. P., Electronic Packaging and Prod., 48 (1979).Google Scholar
14. McCue, D. J., Printed Circuit Assembly, 28 (1990).Google Scholar
15. Allen, B. M., Printed Circuit Assembly, 26 (1989).Google Scholar
16. Chen, W., Printed Circuit Assembly, 38 (1990).Google Scholar