The present disclosure relates to a dielectric substrate that may include a polymer based core film, and a fluoropolymer based adhesive layer. The polymer based core film may include a resin matrix component, and a ceramic filler component. The ceramic filler component may include a first filler material. The particle size distribution of the first filler material may have a D10 of at least about 1.0 microns and not greater than about 1.7, a D50 of at least about 1.0 microns and not greater than about 3.5 microns, and a D90 of at least about 2.7 microns and not greater than about 6 microns.