Mw. Bai et al., Dependence of microstructure and nanomechanical properties of amorphous carbon nitride thin films on vacuum annealing, THIN SOL FI, 376(1-2), 2000, pp. 170-178
Three kinds of ultrathin amorphous carbon nitride films (alpha -CNx) with d
ifferent internal stress were deposited on silicon (111) substrates by an i
on beam assisted deposition method. The as-deposited alpha -CNx was post-an
nealed to eliminate the internal stress. The microstructure and nanomechani
cal properties of both as-deposited and annealed alpha -CNx were studied by
using micro Raman spectroscopy, nanoindentation measurement, and nanoscrat
ch test in atomic force microscopy. The Raman spectra of as-deposited and a
nnealed him show that the ratio of intensities of the D band to G band incr
eased after vacuum annealing. Nanoscratch tests showed that the elimination
of compressive internal stress due to annealing resulted in reduced scratc
h resistance, while elimination of tensile internal stress due to annealing
resulted in enhanced scratch resistance. Nanoscratch test results were in
good agreement with the results of nanoindentation measurement. Experimenta
l results indicate that the effect of internal stress on scratch resistance
is stronger than that of microstructure evolution due to post-annealing. N
anoscratch tests show that suitable compressive internal stress is benefici
al for enhancement of nanoscratch resistance of the thin alpha -CNx film. (
C) 2000 Elsevier Science S.A. All rights reserved.