A Comparison of On-Wafer Microstrip and Grounded Coplanar Waveguide Multiline-TRL Calibration for Millimeter-Wave GaN HEMT Characterization

This paper demonstrates the influence of transmission line configuration on the on-wafer multiline thru-reflect-line (mTRL) calibration and measurement of millimeter-wave gallium nitride (GaN) high electron mobility transistors. Calibration precision is estimated using four different GSG probes, and analyzing variation in on-wafer unmatched transistor measurements with each probe. Microstrip (MS) and grounded coplanar waveguide (GCPW) GaN device measurements are compared. It is shown that the GCPW calibration kit exhibits significantly higher W-band precision than the MS calibration standards investigated in this work.