Calibration Techniques for Millimetre-wave On-wafer S-parameter Measurements (original) (raw)

Accurate characterisation of S-parameters (scattering parameters) at chip level is of great importance to the development of next generation electronic devices. Such measurements are usually carried out on a Vector Network Analyzer (VNA), subject to an on-wafer calibration. Calibration techniques play a key role in determining the accuracy of on-wafer measurements. This paper is intended to provide an overview of conventional calibration techniques, including TRL (Thru, Reflect, Line), Multi-Line TRL, SOLT (Short, Open, Load, Thru), LRM (Line, Reflect, Match), and LRRM (Line, Reflect, Reflect, Match). Advantages and limitations of these different calibration techniques are discussed briefly and summarised. This paper also gives an insight into important factors that influence on-wafer measurement quality. These factors include design of calibration standards, testing environment (boundary and nearby structures), probes pitch sizes, etc.