Pt. Murray et Dt. Peeler, PULSED-LASER DEPOSITION OF CARBON-FILMS - DEPENDENCE OF FILM PROPERTIES ON LASER WAVELENGTH, Journal of electronic materials, 23(9), 1994, pp. 855-859
We have grown thin carbon films by pulsed laser deposition and have in
vestigated the extent to which the properties of such films, as well a
s the processes responsible for these properties, are laser wavelength
dependent. Films were grown by ablating material from a graphite targ
et onto room temperature Si(100) substrates with 1064 and 248 nm laser
radiation. The films were analyzed by in situ electron energy loss sp
ectroscopy and by ex situ Raman spectroscopy. The results indicated th
at films grown with 1064 nm ablation were graphitic, while those grown
with 248 nm radiation were diamond-like. We have also examined the ma
ss and kinetic energy distributions of the particles ejected from grap
hite by the two laser wavelengths. The results indicated that irradiat
ion of graphite with 1064 nm laser radiation results in the ejection o
f a series of carbon cluster ions C(n+)(1 less-than-or-equal-to n less
-than-or-equal-to 30) with mean kinetic energies less than 5 eV. Ablat
ion of graphite with 248 nm radiation results in the ejection of prima
rily C2+ and C3+ with mean kinetic energies of 60 and 18 eV, respectiv
ely. These results suggest that large, low energy clusters produce gra
phitic films, while small, high energy clusters produce films of diamo
nd-like carbon.