Dielectric materials, methods of forming subassemblies therefrom, and the subassemblies formed therewith

A method for the manufacture of a circuit subassembly, comprising:

• providing a core comprising a core dielectric substrate layer having a first surface and an opposite second surface, wherein the composition of said core dielectric substrate layer is based on 1,2-polybutadiene, polytetrafluoroethylene, or a liquid crystal polymer;
• and a first core wiring layer disposed on the first surface of the core dielectric substrate layer;
• and laminating a first dielectric layer, comprising at least 15 weight percent of a dielectric filler, onto the first core wiring layer, wherein the dielectric layer is formed from a dielectric composition comprising, based on the total volume of the composition:
• about 15 to about 65 volume percent of the dielectric filler;
• and about 35 to about 85 volume percent of a thermosetting composition comprising:
• an unmodified poly(arylene ether), and a carboxy-functionalized polybutadiene or polyisoprene polymer;
• wherein the thickness of the first dielectric layer is 75 to about 600 micrometers.