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In this Paper, we have studied and compared the performance of two different configurations of simulation model advanced MOSFET devices which can be used for biosensor application. The bio-molecules like protein, biotin, streptavidin, APTES, etc., undergo label free electrical detection with the help of dielectrical modulation technique in order to overcome the limitations of short channel effect in a more efficient way. The bio-molecules trapped inside the cavity region change the electrical parameters of the MOSFET. Biosensors based on MOSFETs have certain issues, like short channel effects (SCEs) and problems related to scaling and power supply. Therefore the proposed device is better withstand to SCEs and can be consider as an alternative for biosensing applications. For channel material, silicon is used for both the configurations i.e. with stack and without stack model and we have also studied the performance of the device based on the analog as well as RF parameters by considering the protein as bio-molecule in the cavity. Two different oxide materials are used to design the device structure such as HfO2 (K = 25) and SiO2 (K = 3.9) and for simulation purpose the 2D Sentrausu TCAD simulator has been used. The sensing capability of this proposed dielectric modulated device can be applicable for IOT based applications. They can also be uses in health IOT systems for medical research applications and as bio chip sensor in wearable device so as to study the protein content of the human body.

Short channel effects (SCEs) along with mobility degradation has a great impact on CMOS technology below 100 nm. These effects can be overcome by using gate and channel engineering techniques which will improve mobility of the charge carriers, thus eventually improving drain current and trans-conductance of the device. In this work, the speed of operation for DG MOSFET is improved by reducing the channel length where dual-material gate-stack is deployed to avoid the drain-induced barrier lowering (DIBL) and hot carrier effects. In the presented device, the metal closer to the source and drain has higher and lower work function, respectively which causes a significant decrement in the peak electric field at the drain side and so the SCEs. The carrier mobility is also increased due to enhanced electric field in the channel, near the source, caused by higher work function gate material which, in turn, increases the MOSFET’s driving current. The screening effect reducing SCEs and an increment in the acceleration of the charge carriers in the channel are mainly attributed due to higher and lower threshold voltage found near the source and drain, respectively.