Epoxy-based carbon films with high electrical conductivity attached to an alumina substrate

Carbon-based films (0.8–13 μm thick) with good bonding to the substrate and high processability were produced at 650 °C on an alumina substrate, using SU 2.5 bisphenol-A type novolac epoxy (plus triethyleneteramine curing agent) as the carbon precursor. This precursor gave crack-free and scratch resistant carbon films. Interconnected filamentary nickel nanoparticles were more effective for conductivity enhancement than silver nanoparticles or multiwalled carbon nanotubes at 5 vol.% or below, in spite of the high conductivity of silver and the high aspect ratio of nanotubes. The carbon film with 2.5 vol.% nickel showed resistivity 6 × 10−3 Ω cm.