Cold-FET ENR Characterisation Applied to the Measurement of On-Wafer Transistor Noise Parameters

This paper presents a method to characterize the Excess Noise Ratio (ENR) of a Cold - FET (Vds=0V) with the gate reverse-biased, for its application to the measurement of on - wafer FET noise parameters over the microwave and millimetre - wave ranges. The characterisation is performed by determination of a device broadband noise circuit - model, from its measured S-parameters and noise powers. Experimental results up to 40 GHz are given.