Physical modeling and analysis for performance enhancement of nanoscale silicon field-effect transistor-based plasmonic terahertz detector

In principle, the photoresponse can be enhanced by scaling down the gate oxide thickness (tox), which is a key structural parameter for the channel 2DEG density modulation. By using our TCAD simulation framework, we found that the enhanced photoresponse by reducing tox has been originated from the increase of 2DEG density modulation by the improved subthreshold swing (SSW) of FET and the decrease of 2DEG propagation length (i.e. more asymmetric 2DEG) by degradation of the normal field-dependent channel mobility.