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Formation of diamondlike nanocrystallites in amorphous carbon films synthesized by radio-frequency sputtering

Published online by Cambridge University Press:  31 January 2011

D. Wan
Affiliation:
Department of Mechanical Engineering, University of California, Berkeley, California 94720
K. Komvopoulos*
Affiliation:
Department of Mechanical Engineering, University of California, Berkeley, California 94720
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

Transmission electron microscopy (TEM) and fast Fourier transformation (FFT) analysis were used to examine the microstructures of amorphous carbon (a-C) films deposited on Si(100) by radio-frequency (rf) sputtering without magnetron. TEM analysis revealed that a-C films synthesized under certain deposition conditions contained randomly dispersed nanocrystallites ∼35 Å in size. FFT results indicated that the nanocrystallites possessed diamondlike cubic structures with their close-packed {111} planes parallel to the film surface. The formation of diamondlike nanocrystallites is attributed to metastable carbon atom clusters of trigonal carbon hybridization that were sputtered off from the graphite target under certain process conditions. Cluster distortion upon deposition onto the growing film surface by the bombarding Ar+ ions promoted tetrahedral carbon atom hybridization and, possibly, epitaxial growth of diamondlike nanocrystallites for a short duration.

Type
Articles
Copyright
Copyright © Materials Research Society 2008

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References

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