A new approach to on-chip probing in the MM-wave to THz range

One of the bigger obstacles in the development of THz devices and integrated circuits is their electrical characterization in the upper-millimeter to terahertz range above 100 GHz. Today's technology is mainly based on metal-to-metal, dc-coupled contact probes. This technology is, however, expensive and fragile, and is difficult to scale to higher frequencies. This paper concerns contact-free probes that are (ac) coupled to the device or circuit-under-test by the polarization current rather than the conduction current. Numerical simulations are carried out to 1.0 THz and the probe coupling is found to be around -26 dB, with a bandwidth of at least 500 GHz.