Non-contact probes for on-wafer characterization of sub-millimeter-wave devices and integrated circuits

We present a novel non-contact metrology approach for on-wafer characterization of sub-millimeter-wave devices, components, and integrated circuits. Unlike existing contact probes that rely on small metallic tips that make physical contact with the device on the chip, the new non-contact probes are based on electromagnetic coupling of vector network analyzer (VNA) test ports into the coplanar waveguide environment of integrated devices and circuits. Efficient signal coupling is achieved via a quasi-optical link between the VNA ports and planar antennas that are monolithically integrated with the test device. Experimental validation of the non-contact device metrology system is presented for the first time to demonstrate the accuracy and repeatability of proposed approach for the 325-500-GHz (WR2.2) and 500-750-GHz (WR1.5) bands.