Cryogenic sub-THz ultrathin-body InGaAs MOSFET: physical modeling and DC/RF analysis

Cryogenic electronics demand high-performance, high-speed, and high-frequency transistors for various special applications which include space and quantum computers. With the present-day semiconductor processing technologies, it is possible to grow ultrathin III-V layers to fabricate MOSFETs and high-electron-mobility transistors (HEMTs). However, ultrathin-body (UTB) III-V MOSFETs are rarely studied at cryogenic temperatures. In this paper, we presented the detailed physical modeling for cryogenic temperatures to simulate realistic devices. The results are compared with measurement results. Scaled UTB InGaAs MOSFETs with gate lengths <100 nm are simulated and analyzed for DC and high frequencies using TCAD tools. At low temperatures, the UTB InGaAs MOSFET exhibits a low subthreshold swing of \(<60\) mV/dec and transconductance of \(>2\) \(mS/\mu m\). The radio frequency (RF) analysis shows an operating or cutoff frequency \(f_{T}>500\) GHz for a gate length \(L_{G}<50\) nm. These results suggest the suitability of UTB III-V MOSFETs for future cryogenic sub-terahertz applications.