V. Paillard et al., DC CONDUCTION IN DIAMOND-LIKE CARBON-FILMS OBTAINED BY LOW-ENERGY CLUSTER BEAM DEPOSITION, Journal of non-crystalline solids, 191(1-2), 1995, pp. 174-183
Carbon films have been obtained by low-energy cluster beam deposition.
Clusters of different size distributions centered around C-n = 900, 6
0, 20 have been selected because of their very different mean hybridiz
ation: high sp(2) content for C-900, highly sp(3) for C-20, C-60 being
intermediate. Thus, three types of film have been grown and their de
conductivity has been investigated in the temperature range 80-473 K.
The temperature dependence of the conductivity is explained by carrier
hopping and percolation theory. Hopping transport occurs through pi s
tates randomly distributed in energy and in the solid. The pi state de
nsities determined near the Fermi level show that the three types of f
ilm remember the hybridization of the different mean free cluster size
. Conduction properties of the film are compared with those of a-C fil
ms prepared by other techniques.