A Novel Dual Cavity Charge Plasma Based Schottky Barrier MOSFET For Biosensing Application

A novel device architecture of a dual cavity charge plasma-based Schottky Barrier MOSFET (DC CP SB-MOSFET) is proposed and investigated for a wide range of biosensing applications. A dual nanogap cavity is created at the source and drain (S/D) regions under the S/D extension in the proposed device. To pattern the S/D regions, erbium silicide (ErSi) as a metal electrode and hafnium (Hf) metal as an extension of S/D is incorporated to induce the Schottky effect and electrons, respectively. The proposed device uses the concept of dielectric modulation in conjunction with Schottky barrier tunneling for the detection of biomolecules. The charge plasma technique effectively modulates the S/D Schottky tunneling barrier. The presence of different bio-molecules is modeled by their dielectric constant (k) and charge densities (p). The behavior of the device for various bio-molecules is investigated using an energy band diagram (EBD), electric field, surface potential, and tunneling rate. Moreover, analysis of the sensitivity in terms of I
ON
, I
ON
/I
OFF
, sub-threshold slope (SS), and V
th
is studied and explored. The proposed device effectively detects both neutral and charged biomolecules and exhibits several advantages such as higher sensitivity, being free from doping-related issues, and being immune to short-channel effects.