Compensation for Substrate Permittivity in Probe-Tip Calibration

We demonstrate a method of compensation for the effect of substrate permittivity on coplanar waveguide probe-tip scattering parameter calibrations, modeling the effect as a capacitance at the probe tip. Comparison to on-wafer multiline TRL calibration verifies its accuracy. The method allows calibration to the probe tip using generic off-wafer standards with accuracy comparable to that of on-wafer calibration.