Embodiments include semiconductor packages and method of forming the semiconductor packages. A semiconductor package includes first waveguides over a package substrate. The first waveguides include first angled conductive layers, first transmission lines, and first cavities. The semiconductor package also includes a first dielectric over the first waveguides and package substrate, second waveguides over the first dielectric and first waveguides, and a second dielectric over the second waveguides and first dielectric. The second waveguides include second angled conductive layers, second transmission lines, and second cavities. The first angled conductive layers are positioned over the first transmission lines and package substrate having a first pattern of first triangular structures. The second angled conductive layers are positioned over the second transmission lines and first dielectric having a second pattern of second triangular structures, where the second pattern is shaped as a coaxial interconnects enclosed with second triangular structures and portions of first dielectric.