Mobility Fluctuation-Induced Low-Frequency Noise in Ultrascaled Ge Nanowire nMOSFETs With Near-Ballistic Transport

In this paper, we study the low-frequency noise in the Ge nanowire (NW) nMOSFETs with sub-100-nm channel length. The low-frequency noise with 1/ ${f}$ characteristics is proved to origin from the carriers’ mobility fluctuation. The dependences of low-frequency noise on NW geometry, channel length, equivalent oxide thickness (EOT), and channel doping concentration are examined by evaluating the Hooge parameters. It is shown that the low-frequency noise declines when the channel length of Ge NW nMOSFETs scales down, which is attributed to the electrons’ near ballistic transport. The electrons suffer more scatterings in the channels beneath the side walls of NWs or in the highly doped channels. The gate-oxide optimization is strongly demanded with the scaling down of EOT. Ultrascaled Ge NW nMOSFETs promise the enhancement of on-state performance and the suppression of low-frequency noise simultaneously.