Relative rates of nickel diffusion and copper diffusion through gold
- 1 July 1977
- journal article
- letter
- Published by AIP Publishing in Journal of Applied Physics
- Vol. 48 (7), 3144-3146
- https://doi.org/10.1063/1.324045
Abstract
The low‐temperature diffusion of nickel through gold has been evaluated using Auger electron spectroscopy. Samples used were printed‐wiring‐board fingers having a nickel ’’diffusion barrier’’ plated between the copper substrate and the cobalt‐hardened gold contact surface. A coefficient was determined for diffusion via the gold defect structure at 150°C using both first‐arrival and surface‐accumulation approaches. Both methods yield comparable results with a coefficient D′ of (2–7) ×10−15 cm2/sec. This is between one and two orders of magnitude smaller than that determined for copper under nearly identical conditions. Results of other investigations are compared and contrasted to the present findings. The surface reaction of nickel with air and chlorine‐containing environments is sufficiently rapid that diffusion is the rate‐limiting step in the accumulation of nickel at the gold surface.Keywords
This publication has 7 references indexed in Scilit:
- Low-temperature diffusion of copper through goldJournal of Applied Physics, 1976
- Qualitative observations on the diffusion of copper and gold through a nickel barrierMetallurgical Transactions A, 1976
- Diffusion of Cobalt out of Cobalt‐Hardened Gold Measured with Auger Electron SpectroscopyJournal of the Electrochemical Society, 1975
- Ion back-scattering analysis of interdiffusion in Cu-Au thin filmsThin Solid Films, 1973
- Mass diffusion in polycrystalline copper/electroplated gold planar couplesMetallurgical Transactions, 1972
- On measurements of self‐diffusion rates along dislocations in F.C.C. MetalsPhysica Status Solidi (b), 1970
- Strain-Enhanced Diffusion in Metals. II. Dislocation and Grain-Boundary Short-Circuiting ModelsJournal of Applied Physics, 1963