Patent ID: 7476422

Claim:
A process for forming a copper-based circuit, said process comprising the steps of: providing an electrically insulative substrate; forming a bond layer comprising silver over select portions of said substrate according to a desired shape of a circuit; and depositing copper on said bond layer by the steps of: introducing copper particles having a particle size of about 45 microns to about 150 microns into a pressurized carrier gas; forming said pressurized carrier gas and said copper particles into a supersonic jet; and directing said jet toward said bond layer formed over said substrate without use of a mask and from a standoff distance of from 5 to 19 millimeters such that said jet has a velocity sufficient to cause plastic deformation of said copper particles onto said bond layer, thereby forming an electrically conductive layer only on said bond layer in the desired shape of the circuit by selective adherence of said copper particles to said bond layer.