Reroute strategy for high density substrates

Claim 1

A multilayer electrical interconnect substrate for interconnecting a plurality of electrical components, comprising: a plurality of electrical component mounting sites arranged to form horizontal and vertical regions between said sites, said horizontal and vertical regions extending the entire length and width of each of said sites; a custom substrate comprising custom interconnect lines placed within said custom substrate and a plurality of custom vias formed at the terminal ends of each said custom interconnect line; a rerouting substrate connected to said custom substrate and configured between said electrical component mounting sites and said custom substrate, said rerouting substrate comprising: i) a plurality of substantially parallel, X-lines placed in groups within said rerouting substrate, each group of said X-lines configured within horizontal channel regions extending between said electrical component mounting sites and extending substantially the entire length of said rerouting substrate; ii) a plurality of substantially parallel, Y-lines placed in groups within said rerouting substrate, each group of said Y-lines configured within vertical channel regions between said electrical component mounting sites and extending substantially the entire length of said rerouting substrate; said X- and Y - lines overlapping each other at a plurality of cross-over regions where each said horizontal and vertical channel regions intersect; a surface layer connected to said rerouting substrate and placed between said rerouting substrate and said electrical component mounting sites, said surface layer comprising: i) a plurality of outside lead pads surrounding each said electrical component mounting site; ii) a plurality of horizontal channel reroute structures placed within the horizontal channel region, each having a plurality of horizontal channel vias for connecting the horizontal channel reroute structure to a plurality of said X-lines; iii) a plurality of vertical channel reroute structures placed within the vertical channel region, each having a plurality of vertical channel vias for connecting the vertical channel reroute structure to a plurality of said Y-lines; iv) a plurality of channel intersection reroute structures, each channel intersection reroute structure placed within each said cross-over region, each channel intersection reroute structure having a plurality of intersection vias for connecting the channel intersection reroute structure to a plurality of said X-and Y-lines; a plurality of spot links, each spot link having substantially uniform geometry and being receivable on each said horizontal channel reroute structure, on each said vertical channel reroute structure and on each said channel intersection reroute structure for selectively connecting said outside lead pads to said X-lines and said Y-lines; and means for detaching selected ones of said outside lead pads from said custom interconnect lines and for partitioning each said horizontal channel reroute structure, each said vertical channel reroute structure and each said channel intersection reroute structure upon said surface layer.