An architecture for, and techniques for fabricating, a cryogenic microwave filter having reduced Kapitza resistance are provided. In some embodiments, the cryogenic microwave filter can comprise a substrate and a conductive line. The substrate can be formed of a material having a thermal conductivity property that sufficiently reduces Kapitza resistance in the cryogenic environment. The conductive line can be formed in a recess of the substrate and facilitate a filter operation on a microwave signal propagated in a cryogenic environment. In some embodiments, the conductive line can be formed according to a sintering technique that can reduce Kapitza resistance.