Noise and Dynamic Cryogenic performance of Metamorphic Transistors from 20 to 42 GHz

This paper describes the noise and dynamic behavior of commercial MHEMTs characterized at extreme low temperatures (78K and 173K). This is the first time, to our knowledge that the noise performance of metamorphic transistors has been investigated at such low temperatures in this frequency range (from 20 to 42 GHz). The low temperature DC characteristics of these transistors are detailed after a brief introduction describing the main motivations of this study. Then, we describe the dynamic behavior of such components under cryogenic conditions. Finally, noise measurements have also been performed from 20 to 42 GHz, using a non-uniform de-embedding technique. The noise parameters of the transistors, extracted from these measurements, are presented versus the temperature. The results presented show an excellent cryogenic performance at transistor level (NF_min of 0.3 dB and a g_ass of 11.2 dB at 30 GHz and 78K) as well as for a matched MMIC LNA (S21=27 dB, NF=0.4 dB at 30 GHz, at 78K)