Dynamic study on microstructural evolution of nickel germanide utilizing zirconium interlayer

We examined the formation and morphological evolution of germanide formed in a ternary Ni/Zr-interlayer/Ge system using ex situ and in situ annealing experiments. Ni germanide in the Ni/Zr-interlayer/Ge system remained stable at temperatures up to 550 °C whereas Ni germanide in a Ni/Ge system agglomerated and was unstable. Microstructural and chemical analyses of the Ni/Zr-interlayer/Ge system during and after in situ annealing in a transmission electron microscope confirmed that the Zr atoms were retained uniformly on the top region of the Ni germanide layer during the diffusion reaction. Ultimately, the level of agglomeration in the Ni germanide film was reduced by the Zr-interlayer, and the thermal stability of Ni germanide was improved.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► We examined the microstructural evolution of germanide in Ni/Zr-interlayer/Ge system. ► Ni germanide in this system was stable at the higher temperature than that in Ni/Ge system. ► A Zr-rich layer formed by Zr atoms remained on top of the Ni germanide film. ► This Zr-rich layer helped improve the thermal stability of the Ni germanide.