Non-contact probes for THz circuits and integrated devices

We present a new “non-contact” approach for device and circuit testing at THz frequencies. The new non-contact probe design is based on beam-tilted THz antennas integrated into the coplanar environment of the monolithic circuits and devices, such as high-speed transistors and diodes. Commercially available THz vector network analyzers (VNAs) (with extension modules) and waveguide-fed horn antennas are used to excite the beam-tilted planar THz antennas integrated into the test device feed lines. For optimal coupling efficiency, the extended hemispherical lens configuration is used. The propagation effects and the antenna coupling artifacts can be removed using a conventional calibration method using several known loads. Initial results based on the full-wave electromagnetic simulations demonstrate that the new non-contact probe can provide much needed functionality for characterizing new electronic devices and electromagnetic components in the THz regime where standard contact probes are either not available or exceedingly costly.