CMOS THz On-chip surface plasmon polariton T-lines and converter

A low-loss and high bandwidth surface-wave transmission line (T-line) is demonstrated at THz in CMOS. By introducing sub-wavelength periodic corrugation structure onto the T-line (by top-layer metal), surface plasmon polaritons (SPP) is established to propagate signals with strongly localized surface-wave. To be compatible with other on-chip components with TEM-wave propagation, a converter structure featured by a smooth bridge between the coplanar waveguide (CPW) with 50Ω impedance and SPP T-line is proposed. The SPP T-lines and converter are both designed in standard 65nm CMOS process. Simulation results show that the SPP T-line has the ability of strongly confining EM energy and thus achieve wideband low loss transmission. The converter achieves wideband (DC-800GHz) impedance matching with excellent transmission efficiency from CPW to the SPP T-line. The demonstrated compact and wideband SPP T-lines and converter have shown great potential for on-chip THz communication.