Kr. Lee et al., PRECURSOR GAS EFFECT ON THE STRUCTURE AND PROPERTIES OF DIAMOND-LIKE CARBON-FILMS, DIAMOND AND RELATED MATERIALS, 3(10), 1994, pp. 1230-1234
The effect of precursor gases on the diamond-like carbon (DLC) film de
position was investigated in the r.f. plasma-assisted CVD method. DLC
films were deposited using methane or benzene as the precursor gas. Th
e residual stresses, hardnesses, total hydrogen concentrations and ele
ctron energy loss spectra were compared at the same value of V(b)/P1/2
. (Here, V(b) is the self-bias voltage of cathode and P the deposition
pressure.) The values of V(b)/P1/2 ranges from 33 to 250 V mTorr-1/2
for methane and from 33 to 900 V mTorr-1/2 for benzene by changing the
negative bias voltage from -100 to -900 V and deposition pressure fro
m 1 to 100 mTorr. We observed significant differences between the stru
ctures and properties of these films. In the same range of V(b)/P1/2 t
he structure and properties of films deposited from benzene show chara
cteristic behaviors of lower energy deposition than those from methane
. The present observations are discussed in terms of the difference in
the ion energy per carbon atom at the growth surface. The total hydro
gen concentration in the films deposited from benzene is smaller by ab
out 7 at.% in this experimental range.