Influence of Microwave Probes on Calibrated On-Wafer Measurements

On-wafer probing with ground-signal-ground (GSG) probes contributes a variety of side effects, which are related to the measured line type, the carrier material, the layout with the neighboring structures, and the probe. Thus, the size and shape of the probe together with the measured line type and the neighboring circuits influence the quality of the calibrated measured result. This paper presents corresponding results when using the multiline-thru-reflect-line (mTRL) calibration, which is commonly accepted as one of the most accurate calibration algorithms, and concentrates on the impact of the probe construction together with neighboring elements, for the most common planar transmission lines, coplanar waveguides (CPWs), and thin-film microstrip lines (TFMSLs). For the first time, design guidelines with regard to the layout, the measurement environment, and the construction of the probes are given.