Skip to main content Accessibility help
×
Home

In-Situ, Time Resolved, Kinetics of Reactions in Co-Ge thin Films

  • R. M. Walser (a1), Byung-Hak Lee (a1), Alaka Valanju (a1), Winston Win (a1) and M. F. Becker (a1)...

Abstract

We report the first kinetic study of metal-semiconductor interface reactions using in-situ, time resolved, laser interferometry. Diffusion couples with Co/Ge thicknesses of 1500 Å/1500 Å were sputter deposited on silicon wafers, and vacuum-annealed at temperatures between 300°C-400°C. Under these conditions polycrystalline CoGe was expected to form [1]. Real time laser (HeNe 6328 Å) interferograms for each anneal were recorded in-situ. These data were supplemented by information from AES and X-ray.

For temperatures below 400°C the diffusion controlled formation of CoGe was observed. The composition was confirmed by Auger depth profiling that showed uniform Co and Ge concentrations when the reaction went to completion. The well defined interferences fringes were formed by the dissolution of amorphous Ge. The activation energy = 1.6 eV for the formation of CoGe were determined with precision from the temperature dependence of the time required to anneal the fixed λ/4 distance between adjacent minima and maxima of the interferogram. We discuss the evidence for formation of an intermediate Co-rich compound following the initial diffusion of Co into Ge. The results of these experiments indicate that optical interferometry will be a valuable adjunct to other techniques used to study metal-semiconductor interface reactions.

Copyright

References

Hide All
1. Wittmer, M., Nicolet, M-A. and Mayer, J.W, Thin Solid Films 42, 51 (1977).
2. Olson, G.L. and Roth, J.A., Material Science Reports, vol. 3, No. 1 (1988).
3. Park, W.W. and Walser, R.M., J. Mater. Res. 3, 298 (1988).
4. Li, H.H., J. Phys. Chem. Ref. Data, vol. 9, No. 3 (1980).

In-Situ, Time Resolved, Kinetics of Reactions in Co-Ge thin Films

  • R. M. Walser (a1), Byung-Hak Lee (a1), Alaka Valanju (a1), Winston Win (a1) and M. F. Becker (a1)...

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed