Extremely low-noise amplification with cryogenic FETs and HFETs: 1970-2004

This is a review of developments and milestones in the FET and HFET field, including experimental results compared to model predictions. The noise performance of cryogenic FETs and HFETs has made tremendous progress over the last several decades. The most rapid advances seem to have occurred between 1980 and 1995. Three different generations of HFETs were proposed and reduced to practice during that period. Since 1995, no significant new ground has been broken in device technology. However, InP HFET technology has matured and allowed construction of extremely low-noise amplifiers. These amplifiers were used in the construction of several instruments for the investigation of the physics of the early universe.