Water-based Copper Oxide Compositions For Microcircuit Applications

Abstract

For purposes of environmental protection, it is desirable to use water as a solvent to replace organics in electronic materials, Copper oxide compositions and hybrid circuit fabrication processes were developed. These pastes exhibited substantial organic content reduction, while preserving the characteristics of a typical organic-based copper paste. The rapid water evaporation problem of water-based pastes was resolved by providing ionic bonding to attract water while maintaining a stable paste dispersion and rheology. The screen life of this paste under specific temperaturehumidity conditions is reported. Test circuit made from the composition exhibited a resistivity of 2.5-3.0 mW/square/l5 mm. SEM micrographs also showed a dense microstructure similar to that of a copper film made from an organic-based paste.