A thermal management package for a semiconductor device includes a high dielectric constant material substrate, a high thermal conductivity slug disposed in a first window in the high dielectric constant material substrate and held therein by a first bonding material, an outer substrate formed from a material having a low dielectric constant and having a second window formed therein, the high dielectric constant material substrate disposed in the second window in the low dielectric constant outer substrate and held therein by a second bonding material.