L. Barbadillo et al., Amorphous CNx layers from neon electron cyclotron resonance plasmas with N-2 and CH4 as precursors, J ELCHEM SO, 147(10), 2000, pp. 3864-3867
Deposition of amorphous CN, thin films on silicon by electron cyclotron res
onance plasma-enhanced chemical vapor deposition is investigated. The use o
f neon instead of argon to form the plasma promotes species activation and
leads to deposition on silicon substrates. The influence of precursor flow
ratio. addition of hydrogen, and radio frequency power was studied. Optical
emission spectroscopy has been used for the diagnosis of active species in
volved in the deposition process and neither nitrogen nor carbon atomic spe
cies were detected. Fourier transform infrared spectroscopy measurements sh
owed as main bands those related to C-N and C=N bonds. Dielectric constants
of the films were obtained by spectroscopic ellipsometry: samples grown wi
th the highest methane flow ratios showed absorption throughout all the mea
sured energy range, probably due to free carriers. Present results suggest
that CN, layers consist mainly of C-N and C=N bonds in an amorphous matrix,
besides C=C bonds probably in the form of small graphitic clusters. (C) 20
00 The Electrochemical Society. S0013-4651(00)02-016-4. All rights reserved
.