On-Wafer Characterization of Silicon Transistors Up To 500 GHz and Analysis of Measurement Discontinuities Between the Frequency Bands

This paper investigates on-wafer characterization of SiGe HBTs up to 500 GHz. Test structures for on-wafer thru-reflect-line (TRL) calibration have been designed and are presented. The TRL calibration method with silicon standards has first been benchmarked through electromagnetic simulation. Passive and active components are then characterized up to 500 GHz. The slight discontinuities between the frequency bands are explored. A specific focus was placed on incorrect horizontal probe positioning as well as on probe deformation, resulting in a better assessment of possible measurement errors.