Performance investigation of double gate junctionless pMOSFET with asymmetric doping profile for biosensing applications

In this paper, the potential capability of a novel dielectric modulated p-type junctionless MOSFET as a highly sensitive biosensor is demonstrated. A cavity is embedded in the gate insulator region for immobilizing the biomolecules. Absorption of biomolecules in the nanogap changes the gate coupling over the channel and results in the threshold voltage variation. An asymmetric doping profile is introduced in which the channel doing concentration is lower than the related source/drain values for designing a highly responsive biosensor with low static power consumption. Simulation results reveal that by considering maximum length for the nanogap and occupation of the entire volume of cavity, a maximum degree of sensitivity for the biosensor can be achieved. The results of this paper facilitate the integration of biodetection techniques with the existing CMOS technology.