Compact and Low-Crosstalk Terahertz On-Chip Spoof Surface Plasmon Polaritons Based on InP Technology

In this article, a terahertz on- chip spoof surface plasmon polaritons (SSPPs) transmission line (TL) is demonstrated and fabricated via advanced Indium Phosphide (InP) technology. A folded slot SSPPs structure can be applied and etched on the microstrip (MS) line with the characteristic impedance of
$50~\Omega $
, hoping to reduce the occupied area of the conventional SSPPs structure. Through a terahertz on- wafer test system, the proposed die prototype is measured, and the feasibility of the design is verified. Owing to the unique ability of the strong electric field confinement, the proposed SSPPs has excellent characteristics of low-crosstalk compared with MS line under the same transmission losses and footprint. The proposed SSPPs, with the benefits of compact structure and low crosstalk, provide great significance for the terahertz plasmons semiconductor-integrated circuits.