On-wafer Time-Domain Characterization of Microwave Devices

Time-domain methods of characterizing large-bandwidth components become increasingly important due to their ease of interpretation and their applicability to nonlinear and dynamic, non-steady-state processes. We describe error-correction techniques which can significantly enhance the accuracy of on-wafer time-domain measurements using commercially available sampling oscilloscopes and time-domain reflectometry (TDR) systems. Drift, jitter, noise, and bandwidth limitations will be addressed. As an application example, we will present data on the pulse response of advanced Si/SiGe heterojunction bipolar transistors. Advanced techniques using non-linear transmission lines or optical sampling techniques will be reviewed briefly.