Diffusion of nickel in amorphous nickel-zirconium alloys and the composition analysis of nickel-silicide formation in lateral diffusion couples

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1986

OSTI ID:5338904

Barbour, J C

Electron diffraction shows that an amorphous Ni-Zr phase is formed by interdiffusion in a lateral diffusion couple heated below 370/sup 0/C. At 370/sup 0/C, the Zr-rich part of the amorphous alloy begins to crystallize, but subsequent annealing demonstrates that the amorphous phase is stable for 20.5 hours, at 325/sup 0/C. The mobility of Ni in the amorphous alloy, below the crystallization temperature, is much higher than the mobility of Zr; and therefore, the mobility of the Zr determines the ability of the amorphous phase to crystallize. The growth kinetics of amorphous phase formation exhibit a diffusion controlled (time)/sup 1/2/ dependence. A Ni-Si lateral diffusion couple was annealed at 450/sup 0/C for 12 hours and energy dispersive x-ray spectroscopy shows that NiSi grains less than 200 nm long contain a concentration gradient between 0.03 and 0.04 atomic % Ni/nm. The NiSi composition in grains longer than 200 nm is constant and equal to the equilibrium composition, indicating the distance which corresponds to a transition from thin-film growth behavior to thick film growth.

• Research Organization: Cornell Univ., Ithaca, NY (USA)
• OSTI ID: 5338904
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
ALLOYS
AMORPHOUS STATE
CHEMICAL COMPOSITION
DIFFUSION
HIGH TEMPERATURE
NICKEL ALLOYS
NICKEL COMPOUNDS
NICKEL SILICIDES
PHASE STUDIES
SILICIDES
SILICON COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
ZIRCONIUM ALLOYS