A. Laskarakis et al., A study on the bonding structure and mechanical properties of magnetron sputtered CNx thin films, DIAM RELAT, 10(3-7), 2001, pp. 1179-1184
Carbon nitride (CN,) films have been deposited by reactive (RF) magnetron s
puttering, in order to investigate the effect of the energetic ion bombardm
ent during deposition (IBD), in terms of applied V-b, on their bonding stru
cture. Fourier Transform IR Ellipsometry (FTIRE) and X-ray photoelectron sp
ectroscopy (XPS) were used for the investigation of the films bonding struc
ture, while their mechanical properties were evaluated by nanoindentation m
easurements. At films grown with low negative V-b, (low energy IBD) the N a
toms are distributed homogeneously in substitutional sites in graphitic rin
gs through both sp(2) and sp(3) bonds and in linear chains, through sp(2) b
onds. In contrast, the high negative V-b (high energy IBD) has been suggest
ed to promote the non-homogeneous N distribution at localized regions in th
e films where the formation of sp(3) C-N bonds is favored. This behavior wa
s also evidenced by the C1s and N1s XPS peak components, assigned to the sp
(3) and sp(2) carbon-nitrogen bonds. Also, high energy IBD films revealed i
ncreased values of hardness and elasticity, while hardness values up to 45
GPa were measured at localized regions. (C) 2001 Elsevier Science B.V. ALL
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