On-Wafer Terahertz Ribbon Waveguides Using Polymer–Ceramic Nanocomposites

This paper investigates the design and fabrication of thin dielectric ribbon waveguides for terahertz (THz) circuit applications. Simulations indicate that dielectric thin ribbon waveguides provide low loss THz wave propagation when a combination of high dielectric constant (high-
$k$
) core and low dielectric constant (low-
$k$
) cladding are used. This combination provides stronger field confinement which helps in reducing losses at waveguide bends and allows higher density integration. Two different fabrication approaches are investigated: 1) photopatterning of spin coated nanocomposite thin films and 2) laser cutting of dry nanocomposite thin films. Characterization of nanocomposites-based waveguides is carried out over a wide frequency range in the THz spectral region. Measurements of a variety of different waveguide samples validate the simulated results and prove that low cost, wafer-level planar THz integrated circuits can be realized with polymer ceramic nanocomposite thin ribbon waveguides.