28 FDSOI RF Figures of Merit down to 4.2 K

Nyssens, Lucas [UCL] Halder, Arka [UCL] Planes, N. [ST-Microelectronics, 850 rue J. Monnet, 38926 Crolles, France] Flandre, Denis [UCL] Kilchytska, Valeriya [UCL] Raskin, Jean-Pierre [UCL]

This work presents a detailed RF characterization of 28 FDSOI nMOSFETs at cryogenic temperatures down to 4.2 K. Two main RF Figures of Merit (FoMs), i.e. current gain cutoff frequency (fT) and maximum oscillation frequency (fmax), as well as parasitic elements of the small-signal equivalent circuit are extracted from the measured S-parameters. The observed behavior of RF FoMs versus temperature is discussed in terms of small-signal equivalent circuit elements, both intrinsic and extrinsic (parasitics). This study suggests 28 FDSOI nMOSFETs as a good candidate for future cryogenic applications down to 4.2 K and clarifies the origin and limitations of the performance.