Growth kinetics of amorphous interlayers by solid-state diffusion in polycrystalline Zr and Hf thin films on (111)Si

Journal Article · Mon Oct 15 04:00:00 EDT 1990 · Journal of Applied Physics; (USA)

DOI:https://doi.org/10.1063/1.346262· OSTI ID:6181030

Cheng, J Y; Chen, L J ^[1]

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1. Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, Taiwan (People's Republic of China)

The growth kinetics of an amorphous ({ital a}-)interlayer in polycrystalline Zr and Hf thin films on (111)Si have been investigated by cross-sectional transmission electron microscopy. The growth of the {ital a}-interlayer in group-IVb metals and silicon systems was found to exhibit similar behaviors. The growth was found to follow a linear growth law initially. The growth rate then slows down and deviates from a linear growth law as a critical thickness of the {ital a}-interlayer was reached. Crystalline silicide (ZrSi or HfSi) was found to nucleate at the {ital a}-interlayer/Si interface in samples after prolonged and/or high-temperature annealing. Silicon atoms were found to be the dominant diffusing species during the formation of amorphous alloys. The activation energy of the linear growth and maximum thickness of the {ital a}-interlayer were measured to be 1.4 eV, 17 nm and 1.2 eV, 27 nm in Zr/Si and Hf/Si systems, respectively. The correlations among the differences in atomic size between metal and Si atoms, growth rate and activation energy of the linear growth, critical and maximum {ital a}-interlayer thickness, the largest heat of formation energy for crystalline silicides, the calculated free-energy difference in forming amorphous phase, as well as the atomic mobility in Ti/Si, Zr/Si, and Hf/Si systems are discussed.

• OSTI ID: 6181030
• Journal Information: Journal of Applied Physics; (USA), Journal Name: Journal of Applied Physics; (USA) Vol. 68:8; ISSN 0021-8979; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360601* -- Other Materials-- Preparation & Manufacture
AMORPHOUS STATE
CRYSTALS
DIFFUSION
ELECTRON MICROSCOPY
ELEMENTS
FILMS
HAFNIUM
HAFNIUM COMPOUNDS
HAFNIUM SILICIDES
KINETICS
LAYERS
METALS
MICROSCOPY
NUCLEATION
POLYCRYSTALS
REFRACTORY METAL COMPOUNDS
SEMIMETALS
SILICIDES
SILICON
SILICON COMPOUNDS
SUBSTRATES
THIN FILMS
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
TRANSMISSION ELECTRON MICROSCOPY
ZIRCONIUM
ZIRCONIUM COMPOUNDS
ZIRCONIUM SILICIDES