Surface mountable microwave IC package.

@ A surface mountable microwave IC package uses printed transmission lines on a printed circuit board in lieu of plumbing between milled packages. A backside co-planar waveguide is connected to a topside microstrip line by a through-hole in a carrier substrate. To compensate for inductance added by the hole and transmission line ends, a gap is adjusted to provide compensation capacitance. Hermeticity is assured by brazing a lead frame over the through-hole and using a solder sealed lid. The lid provides both hermeticity and shielding.