Dilute NiPt alloy interactions with Si

doi:10.1016/0169-4332(93)90166-9

Applied Surface Science

Volume 73, 2 November 1993, Pages 197-202

https://doi.org/10.1016/0169-4332(93)90166-9 Get rights and content

Abstract

The reaction between a dilute Ni₉₅Pt₅ alloy and <111>Si has been investigated as a function of the annealing temperature and time, and the film thickness. Contrary to the concentrate alloys the first phase formed is Ni₂Si and the growth kinetics in the initial steps are similar to the case of pure Ni. Pt segregates in the alloy and its presence slows down the silicide growth rate suggesting that a new mechanism, namely the release of Ni from the alloy, is competing with the diffusion process in the silicide. In all the cases here considered NiSi starts to form only when all the Ni is reacted, indicating that the Pt never reaches high enough concentrations to inhibit the Ni₂Si growth. The further evolution of the system is similar to the ones reported for bilayers and non-dilute alloys. The I–V characteristics measured after annealing give a barrier height of 0.70 ± 0.01 eV.

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Dilute NiPt alloy interactions with Si

Abstract

Mater. Sci. Rep.

Mater. Sci. Rep.

Mater. Sci. Rep.

J. Appl. Phys.

Thin Solid Films

Thin Solid Films

Thin Solid Films