Enhanced morphological and thermal stabilities of nickel germanide with an ultrathin tantalum layer studied by ex situ and in situ transmission electron microscopy.
The formation and morphological evolution of germanides formed in a ternary Ni/Ta-interlayer/Ge system were examined by ex situ and in situ annealing experiments. The Ni germanide film formed in the Ni/Ta-interlayer/Ge system maintained continuity up to 550°C, whereas agglomeration of the Ni germanide occurred in the Ni/Ge system without Ta-interlayer. Through microstructural and chemical analysis of the Ni/Ta-interlayer/Ge system during and after in situ annealing in a transmission electron microscope, it was confirmed that the Ta atoms remained uniformly on the top of the newly formed Ni germanide layer during the diffusion reaction. Consequently, the agglomeration of the Ni germanide film was retarded and the thermal stability was improved by the Ta incorporation.
School of Advanced Materials Science & Engineering, Sungkyunkwan University, Suwon 440-746, South Korea.
Jae-Wook
JW
Lee
Hyung-Kyu
HK
Kim
Jee-Hwan
JH
Bae
Min-Ho
MH
Park
Hyoungsub
H
Kim
Jiho
J
Ryu
Cheol-Woong
CW
Yang