Metallic nanowire filled membrane for slow wave microstrip transmission lines

A new concept of slow wave microstrip transmission lines (SW µTL) dedicated to mmW and sub-mmW applications (100 GHz and further) is described herein. The microstrip is deposited on a specific substrate consisting in a metallic nanowires-filled membrane (MnM) of alumina covered with a thin top layer of silicon oxide. The slow wave effect is obtained thanks to metallic nanowires that capture the electric field while the magnetic field can extend in the whole substrate. Despite of the strong miniaturization expected, such SW µTLs should reach a quality factor five times higher than the one obtained with a conventional microstrip line (without nanowires). Such SW µTL can act as interconnecting paths if the MnM substrate is used as a 3D-interposer.