Impact of process and device dimensions on Bio-TFET Sensitivity

This paper reports the impact of process and dimensions on the sensitivity of the double gate Bio-TFET for drain and source underlap structures. The Bio-TFET is simulated using different dielectric permittivity materials (ε) localized over the drain to gate and gate to source underlap regions. The impact of silicon thickness (t
_Si
), gate oxide (t
_ox
), underlap length at the source (L
_US
) and at the drain region (L
_UD
) were studied. The best sensitivity for BioTFET biosensor is obtained for the source underlap (L
_US
) of 25 nm, channel silicon thickness of 5 nm and gate oxide thickness of 3 nm. The energy band diagram and the band-to-band tunneling generation rate were used to explain the results.