This paper presents experimental results on the electrical properties of hydrogenated amorphous carbon films(a-C:H) prepared by I`ECVD. DC conductance of a-C:I-I was measured as a function of temperatures in the range of 100 to 423K. We studied two a-...
This paper presents experimental results on the electrical properties of hydrogenated amorphous carbon films(a-C:H) prepared by I`ECVD. DC conductance of a-C:I-I was measured as a function of temperatures in the range of 100 to 423K. We studied two a-C:H films: one was well explained by the Mott`s Variable Range Hopping(VRH) rule. but the other sample did not follow it. However, the conduction data of second sample were well fitted to Shimakawa`s Multi-Phonon Hopping(MPH) model according to which conductivity is proportional to T^M with m=15-17. but, in our samples, m was 10-12. Also a-C:H showed several bias effects like relaxation of conductance, bias-dependent conductance and the change of conductance slope in In(σ√T) vs. T^¼ plot. In this study we interpret these data by bias-dependent detrapping model.