Generalization and Reduction of Line-Series-Shunt Calibration for Broadband GaAs and CMOS On-Wafer Scattering Parameter Measurements

This paper presents generalization and reduction of the line-series-shunt (LST) calibration technique, including generic parasitic treatments on the series/shunt standards and number reduction of calibration standards, for broadband GaAs and CMOS on-wafer scattering parameter (S-parameter) measurements. The series/shunt standards are modified with additional transmission-line (TL) sections on both the left and right sides to directly solve the five calibration parameters, namely, TL propagation constant, series impedance, shunt admittance, series parasitic admittance, and shunt parasitic impedance. This approach relaxes the constraint on the series/shunt standards that may not satisfy the plain lossy TL assumption in the parasitic evaluations. The calibration can be further reduced by only two standards if the lossy TL models for the series/shunt standards are satisfied. These points are examined by a microstrip test structure built on GaAs and CMOS technologies, with verification of an independent thru-reflect-line calibration.