Verification of LRRM Calibrations with Load Inductance Compensation for CPW Measurements on GaAs Substrates

The microwave on-wafer measurement community has been searching for a mechanism to quantify calibration inaccuracies. Recent work at the National Institute of Standards and Technology (NIST) has enabled the determination of calibration error bounds by comparison with a well understood technique - the NIST multi-line GaAs TRL calibration. A series of automated Line-Reflect-Reflect-Match (LRRM) calibrations with load inductance compensation were performed on commercially available alumina coplanar waveguide standards. These calibrations were then compared with an NIST calibration. The calculated error bounds were determined and compared in order to assess both the relative accuracy and the repeatability of the automated calibrations.