We measure the electrical parameters of commercial lumped-element impedance standards manufactured for the calibration of on-wafer probing systems. The standard's impedance depends not only on the standard itself, but also on probe placement, probe construction, and the reference calibration.
and Walker, D.
Lumped-Element Impedance Standards, Tech Dig., Auto. RF Tech. Group Conf., Baltimore, MD, [online], https://doi.org/10.1109/ARFTG.1998.327285
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