Skip to main content
mTRL Standards and Calibration for Accurate mm-Wave Transistor Characterization
The RF instrumentation industry has released commercial passive and active load-pull systems that enable large signal characterization above 100GHz in response to recently developed semiconductor-based transistor technologies that have improved performance in the upper bands of the mm-wave frequencies. Although the multiline Thru-Reflect-Line (mTRL) calibration method has been broadly adopted by the RF community, a rigorous on-wafer calibration procedure must be followed as we enter the mm-wave frequency bands, where various measurement error mechanisms can dramatically lead to erroneous characterization. We will review the critical steps of the mTRL calibration and discuss current difficulties with the design of adequate on-chip standards. We will present new approaches to calibration kit design that considerably mitigate the risk of measurement errors at mm-wave frequencies. We also will propose techniques to verify that the assumptions and approximations made during the mTRL calibration are valid under specific circumstances. Finally, we validate these new approaches with comparative studies and the demonstration of accurate transistor characterization with reduced errors up to 325GHz.