AbstractMicrowave probes are used extensively for linear and nonlinear characterization of microwave devices on wafer and are commercially available for use at frequencies up to 65 GHz. An on‐wafer noise measurement test system, for discrete devices, is now commercially available and on‐wafer power measurement techniques are emerging slowly. These probes are also getting more recognition for the testing of packaged chips, packages, and modules. More accurate calibration techniques and their on‐wafer validation are being developed. Automatic testing of MMIC wafers, using an integrated test system, is a key requirement for the development of low‐cost IC pro