Thermosetting electroconductive paste for electroconductive bump use

摘要

The invention is directed to a thermosetting electroconductive paste for forming electroconductive bumps at predetermined locations on at least one circuit layer that is laminated to an insulating layer. Upon lamination the electroconductive bumps penetrate the insulating layer forming an electrical connection to a second circuit layer. The paste comprises, based on total composition, 80 to 90 wt % electroconductive powders comprising at least a first and second electroconductive metal powder of which packing densities are in the range of 20% or less of the average density (sp. gr.) of metal for the first powder and 20 to 40% of the average density (sp. gr.) of metal for the second powder; and 10 to 20 wt % epoxy resin, curing agent, and solvent.