70 kHz-145 GHz broadband S-parameter measurements: Calibration and verification possibilities

As wider bandwidth S-parameter measurements are used for device modeling and other characterizations, it may be appropriate to revisit some assumptions about calibration and verification models. For fixtured, on-wafer and coaxial measurements in the range up to 150 GHz, we will examine load standard and related model fitting behavior for some common technologies, reflection standard behaviors and the appropriateness of mismatched lines as verification elements. Some of the element models appear to require minor modifications but otherwise reasonable performance was observed including residual source match and directivity values well in excess of 30 dB across the frequency range. The above efforts allow for an initial uncertainty calculation whose behaviors do not differ dramatically from that seen in the previous generation of broadband measurements.