A novel probe station for helium temperature measurements

A novel automated wafer-level RF measurement system is presented. It includes a wafer prober and dedicated on-wafer probe tips and calibration standards. Probe station related design issues are discussed leading to a system for automated testing of wafers up to 300mm by using a programmable positioning stage. Using on-wafer SiGe HBT measurements, noise characterization and VNA calibration verification, the long-term stability and reliability of the setup is illustrated. Tests are carried out both with liquid nitrogen as well as liquid helium as coolant, equal to temperature range from 400K down to 4K.