Abstract
Thick film conductors based on Al, Cu and Ni have been studied. Because of its high depth of field, a SEM was used to study the microstructures of the fired conductors.Because of the very small size of the particles in commercial Cu pastes the neck growth forms part of the grain growth mechanism.The bonding between the particles is much stronger in Cu than in Al films; this seems to be the reason why the sheet resistance of a Cu film virtually reaches the theoretical minimum.