Direct On-Wafer Measurements of Noise Parameters in C- and X-bands at $T=4$ K

TL;DR

This paper presents a cryogenic on-wafer measurement setup for noise parameters of FETs in the 5-12 GHz range at 4K, enabling simultaneous calibration and measurements of multiple devices.

Contribution

It introduces a comprehensive cryogenic measurement setup and calibration procedure for accurate noise parameter characterization at cryogenic temperatures.

Findings

First measurements of 14nm FinFET noise parameters at 4K.

Noise temperature values compared with alternative techniques.

Simultaneous calibration and measurement of multiple FETs.

Abstract

This paper describes the setup and the results of the direct on-wafer measurements of a FET noise parameters obtained with a source-pull method at temperatures down to T=4K and in the 5-12 GHz frequency range. The setup consists of a cryostat with wafer probes, two reflectometers, a programmable impedance generator, wideband isolators and bias tees and low noise preamplifier, all cooled to cryogenic temperatures, allowing to perform a full vector error-corrected wafer-level measurements of the discrete transistors and amplifier dies. The setup and its calibration procedure are designed in a such way that allows simultaneous calibration, S-parameters, noise parameters and I-V curve measurements of several FETs all in one cooldown. Using the described setup we perform first measurements of 14nm FinFETs and also measure noise parameters of an LNA based on these FETs. Resulting noise temperature values are compared against those obtained using independent and alternative measurement techniques.