Chapter 38. Effect of Substrate and Pretreatment on Copper to AIN Direct Bonds

  1. John B. Wachtman Jr
  1. W. L. Chiang,
  2. V. A. Greenhut,
  3. D. J. Shanefield,
  4. L. Salvati and
  5. R. L. Moore

Published Online: 26 MAR 2008

DOI: 10.1002/9780470313848.ch38

Proceedings of the 15th Annual Conference on Composites and Advanced Ceramic Materials, Part 2 of 2: Ceramic Engineering and Science Proceedings, Volume 12, Issue 9/10

Proceedings of the 15th Annual Conference on Composites and Advanced Ceramic Materials, Part 2 of 2: Ceramic Engineering and Science Proceedings, Volume 12, Issue 9/10

How to Cite

Chiang, W. L., Greenhut, V. A., Shanefield, D. J., Salvati, L. and Moore, R. L. (1991) Effect of Substrate and Pretreatment on Copper to AIN Direct Bonds, in Proceedings of the 15th Annual Conference on Composites and Advanced Ceramic Materials, Part 2 of 2: Ceramic Engineering and Science Proceedings, Volume 12, Issue 9/10 (ed J. B. Wachtman), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470313848.ch38

Author Information

  1. Department of Ceramics, College of Engineering, Rutgers University, Piscataway, NJ 08855-0909

Publication History

  1. Published Online: 26 MAR 2008
  2. Published Print: 1 JAN 1991

ISBN Information

Print ISBN: 9780470375105

Online ISBN: 9780470313848

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Keywords:

  • preoxidation;
  • alumina;
  • electronic;
  • eutectic;
  • microscope

Summary

It was found that copper-aluminum nitride bond strength depends on the particular source of AIN substrate and the preoxidation treatment of the substrate. Direct bonding of copper to AIN substrate was achieved through the use of the gas-metal euteclic method. A satisfactory, reliable bond could be achieved by oxidizing the surface of AIN substrate prior to bonding to copper. The strength of the bond in a peel lest ranged from 15 to 56 Nlcm depending upon substrate and pretreatment. Studies of the fracture mode for copper bonded to various pretreated AIN substrates showed that the failure interface changed with the surface oxide thickness. This could be related to a residual stress between the surface oxide and the AIN substrate resulting from thermal expansion mismatch. Using the best preoxidation treatment, the bond strength with substrates from one supplier differed by a factor of three from the bond strength with substrates from another supplier. A preliminary study showed that this might be attributed to different silicon content on the preoxidized AIN surface. This could alter the thermal expansion coefficient of the surface oxide layer and generate a smaller interfacial residual stress, which in turn results in a higher bond strength. A difference in calcium level may also enhance bond strength as found in prior studies of copper-alumina bonding.