Patent ID: 8499440

Claim:
A method of making a circuitized substrate, said method comprising: providing a core dielectric layer including a supporting dielectric sub-layer including a plurality of fibers having a low coefficient of thermal expansion and a halogen-free resin, and a second dielectric sub-layer of a low moisture absorptivity resin having a moisture absorption between 0% and 0.50% when immersed in water for a period of about 24 hours at a temperature of about 22° C., and a quantity of inorganic particulates, said second dielectric sub-layer not including continuous or semi-continuous fibers or the like as part thereof, said second dielectric sub-layer being disposed proximate said supporting dielectric sub-layer; and placing at least one circuitized layer on either of the group: said supporting dielectric sub-layer and said second dielectric sub-layer.