Formation and structure of epitaxial NiSi2 and CoSi2

doi:10.1016/0040-6090(82)90098-0

Thin Solid Films

Volume 93, Issues 1–2, 9 July 1982, Pages 135-141

https://doi.org/10.1016/0040-6090(82)90098-0 Get rights and content

Abstract

Transmission electron microscopy has been applied to study the formation and structure of epitaxial NiSi₂ and CoSi₂ thin films on silicon. Bright field and dark field imaging reveal the interface planes of faceted silicides through the strain contrast, analogous to the contrast of the precipitate-matrix interface of coherent or semicoherent precipitates. Superlattice dark field imaging depicts the distribution of twin-related and epitaxial silicides in these systems. {111} interfaces were found to be more prominent than {001} interfaces. Twin-related silicides were observed to cover more area on the substrate silicon than epitaxial silicides did.

In situ annealing of nickel and cobalt thin films on silicon provides a unique means of investigation of the transformation from polycrystalline to epitaxial silicides. The NiSi₂ transformation was found to be very rapid at 820°C, whereas the CoSi₂ transformation appeared to be very sluggish. Furnace annealing confirmed that only a small fraction of CoSi₂ transforms to epitaxial CoSi₂ after annealing at 850°C for 4 h.

Diffraction contrast analysis has been applied to interfacial dislocations of epitaxial NiSi₂/Si and CoSi₂/Si systems. The dislocations were found to be of edge type with $16$ 〈112〉 and $12$ 〈110〉 Burgers' vectors. The average spacings are close to their respective theoretically predicted values.

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^☆: Paper presented at the Symposium on Thin Films and Interfaces, Boston, MA, U.S.A., November 16–19, 1981.

^†: Permanent address: Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, Taiwan.

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Formation and structure of epitaxial NiSi2 and CoSi2☆

Abstract

Thin Solid Films

Thin Solid Films

Acta Metall.

Jpn. J. Appl. Phys., Suppl.

Appl. Phys. Lett.

Appl. Phys. Lett.

Formation and structure of epitaxial NiSi₂ and CoSi₂☆