Lake Shore offers microwave configurations with ground-signal-ground (GSG) probe geometry optimized for substrates patterned with coplanar waveguide structures. Both signal and ground traces of the microwave structures must be patterned on the top layer of the substrate to facilitate top side probing. Measurements can be performed on both passive and active devices to characterize performance metrics such as S-parameters, noise figure, or load-pull parameters.
Use of GSG microwave probes is more complex than of DC/RF probes. Proper probe alignment of the GSG points with respect to the test substrate is required, and the probe must be planarized with respect to the plane of measurement. Also, calibration may be desired to separate the frequency dependent losses of the measurement setup from the actual device under test.