An integrated circuit structure includes an interconnect structure over a semiconductor substrate and a coaxial transmission line. The coaxial transmission line includes a signal line, a top plate over the signal line and electrically insulated from the signal line, and a bottom plate under the signal line and electrically insulated from the signal line. At least one of the top plate and the bottom plate includes metal strip shields and dielectric strips, with each of the dielectric strips being between two of the metal strip shields. The integrated circuit structure further includes a ground conductor electrically connecting the top plate and the bottom plate. The ground conductor is insulated from the signal line by a dielectric material. According to the invention, the characteristic impedance and the characteristic wavelength can be adjusted by the adjustment of a distance between the grounding conductive objects, and the process for manufacturing the coaxial transmission line is fully compatible with a process for manufacturing a CMOS circuit.