Experimental studies aiming at the elucidation of the as yet poorly un
derstood growth mechanisms of DLC films from C+ ions are described. Th
ree main characterization methods are employed: (i) atomic force micro
scopy (AFM) for nanometer characterization of the surface morphology;
(ii) Rutherford backscattering spectroscopy (RBS) combined with profil
ometry for density measurements; and (iii) electron energy loss spectr
oscopy (EELS) for analysis of the bonding configuration (sp(3)/sp(2)).
DLC films were deposited on Si substrates using mass selected C+ ions
with well-defined energies in the range 5 eV-2 keV at different subst
rate temperatures in the range 25-250 degrees C. The data indicate tha
t sp(3) film deposition is associated with internal subsurface growth
of very smooth films while sp(2) rich film formation is associated wit
h surface growth processes of much rougher films. The data is in accor
d with and substantiates the subplantation model that treats low energ
y ion beam deposition in terms of a shallow implantation process.