Brinda Bhowmick - Academia.edu (original) (raw)

Papers by Brinda Bhowmick

Applied Physics A, 2020

This paper investigates the reliability of the selective buried oxide TFET δp + silicon-germanium... more This paper investigates the reliability of the selective buried oxide TFET δp + silicon-germanium layer at the tunneling junction. The impact of various uniform and Gaussian trap distributions and energies on the band-to-band tunneling current has been examined. The device has been optimized for different gap positions in the buried oxide. The OFF current of the proposed device is 1.7 × 10 −18 A/µm. It has been observed that the effect of Gaussian trap is more compared to that of uniform trap. The study quantifies the DC parameters such as I ON /I OFF ratio, subthreshold swing against different types of interface traps (donor or acceptor), density (Dit), position (near the tunneling junction or oxide/channel interface) and trap energy level (E trap). Drain current reduces in the presence of acceptor-type trap and the variation is more for large trap density (1 × 10 14 cm −3). An opposite behavior is perceived in the presence of donor-type traps. The device with highest acceptor trap concentration (1 × 10 14 cm −3) provides minimum ON current of 2.21 × 10 −6 A/µm whereas in case of donor trap concentration (1 × 10 14 cm −3), highest ON current of 2.93 × 10 −5 A/µm is obtained. The device with no traps proves to be better by providing maximum I ON /I OFF ratio of 3.89 × 10 12 with SS of 45 mV/dec. Further, the affectability of quantum correction on various electrical parameters has been studied for different types of traps.

Materials Science and Engineering: B

Silicon

In this review, we explored the modern development of schottky field effect transistor (SK FET) s... more In this review, we explored the modern development of schottky field effect transistor (SK FET) structures and the improvement of sensitivity of nanowire sensors using dielectric modulation. Here, the recent developments compared with the conventional schottky FET sensor, and modified conventional configuration have improved sensitivity and faster responses controlled by dielectric modulation and changing the barrier height. The change in sensitivity-with the current optimization has been considered for dissimilar gate, and drain voltage. The dielectric modulation can advance the finding limits, sensitivity, and reaction time of the novel structures in dissimilar applications, such as U-V finding, gas and chemical/ biosensing. In addition, the efficiency and doped channel have been deliberately studied under dissimilar biomolecule model specifications. This article reviews a recent study on emerging future generation SK FET biosensors with their sensitivity performance and the effect of their metal and channel contact is presented.

2021 International Conference on Computational Performance Evaluation (ComPE)

This work reports the fundamental concepts on n+ pocket Vertical Tunnel FET (VTFET). An optimizat... more This work reports the fundamental concepts on n+ pocket Vertical Tunnel FET (VTFET). An optimization strategy that is applicable to any TFET geometry is presented to optimize its electrical parameters. Furthermore, the optimized device geometry is tested for its reliability under non-ideal situation. Examination of device characteristics has been done considering impact of interface trap charges. Two types of trap charge distributions viz. uniform and Gaussian are taken into account. Temperature affectability is also studied to find out the range of operating temperature of the device. Finally, the RF characterization of the device is carried out to check its viability in high frequency applications.

Sub-Micron Semiconductor Devices, 2022

2013 IEEE International Conference on Signal Processing, Computing and Control (ISPCC), 2013

ABSTRACT This paper presents the Green Function formalism for hetero double gate nano scale Tunne... more ABSTRACT This paper presents the Green Function formalism for hetero double gate nano scale Tunnel FET drain current. In nano-transistors where the channel length is comparable to the electron mean free path, nonstationary or even ballistic transport is probably of great importance regarding the device performance. A generalized Green's function is derived for vector electric potentials. The drain current is derived using numerical simulation and compared with drain current obtained from Schrodinger's wave equation method that accounts for the quantum confinement effect. Finally, it is observed that for ultra short channel Tunnel FETs, the two model results shows close match at ballistic channel length.

VLSI and Post-CMOS Electronics. Volume 1: Design, modelling and simulation, 2019

In this chapter, the principle of operation of tunnel FET is discussed. Existing models and modif... more In this chapter, the principle of operation of tunnel FET is discussed. Existing models and modified structures including gate, source and drain engineering are explored and investigated. It depicts the application of tunnel FET in a digital circuit and as biosensor. It is found that TFET has reduced power consumption and can be used in low-power applications. Further, it acts as a better biosensor.

Ferroelectrics

Abstract We have reported the impact of work function variability (WFV) of TiN metal gate on the ... more Abstract We have reported the impact of work function variability (WFV) of TiN metal gate on the variation in electrical parameters for negative capacitance FinFET (NC-FinFET) through TCAD simulator. It is found that as the thickness of ferroelectric layer (tFE) increases, the fluctuation in electrical parameters like threshold voltage (σVT), subthreshold swing (σSS), on current (σIon), and off current (σIoff) are decreases at different average grain size (). However, the increase in leads to more fluctuation in electrical parameters. It is also observed that the distribution of electrical parameter is close to normal for small and bounded for large

2022 2nd International Conference on Artificial Intelligence and Signal Processing (AISP)

Due to the requirement in recent years, the semiconductor industry have used the channel material... more Due to the requirement in recent years, the semiconductor industry have used the channel material beyond Silicon. In this paper, a dual material gate (DMG) FinFET is designed and two different channel materials like Ge and GaAs is considered in simulation. The transfer characteristic of DMG-FinFET is compared for two different channel materials like Ge and GaAs. A comparative analysis of RF/analog parameters like transconductance (g<inf>m</inf>), output conductance (g<inf>d</inf>), gate capacitance (C<inf>GG</inf>), intrinsic gain (g<inf>m</inf>/g<inf>d</inf>), cut off frequency (f<inf>t</inf>), and gain frequency product (GFP) is also discussed. Results show that Ge DMG-FinFET has higher value of I<inf>on</inf>/I<inf>off</inf>. Investigation also reveals that Ge DMG-FinFET has higher value of g<inf>m</inf>, gain (g<inf>m</inf>/g<inf>d</inf>), and ft than GaAs DMG-FinFET in weak to moderate inversion region.

Sub-Micron Semiconductor Devices, Mar 26, 2022

Journal of Materials Science: Materials in Electronics, 2022

Attributable to the rapid increase in human infection of Coronavirus disease 2019 (COVID-19) caus... more Attributable to the rapid increase in human infection of Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the World Health Organization (WHO) has declared this disease outbreak as a pandemic. This outbreak can be tackled to some extent through proper management and early diagnosis. This work reports a biosensor based on vertical tunnel field-effect transistor (VTFET) developed for the detection of SARS-CoV-2 from the clinical samples through the analysis of its spike, envelope, and DNA proteins. Investigation of the sensitivity of the proposed sensor has been done by calculating the shift in drain current. The dielectric constant equivalent of the virus proteins is used to represent the hybridized biomolecules within the nanogaps. The sensitivity of this proposed sensor is found to be significantly high (order of 10 6) showing the viability of the device to be a superior sensor. Furthermore, the sensitivity analysis concerning DNA charge density is also performed. The effect of DNA charge density variation on the threshold voltage (V th) and sensitivity have also been studied in this work. The proposed sensor is also investigated for its noise performance and observed the sensitivity with and without the effect of interface trap charges. Finally, the proposed sensor is benchmarked against the sensitivity of various FET-based biosensors already published earlier.

Lecture Notes in Electrical Engineering, 2022

IEEE Sensors Journal, 2021

This paper reports an extensive comparison of a hetero-stacked source tunnel field effect transis... more This paper reports an extensive comparison of a hetero-stacked source tunnel field effect transistor (TFET) and heterostructure vertical TFET as label-free biosensors based on dielectric modulation. Due to the difference in the TFET design, the vertical TFET possess highrer sensitivity, ON-state current, textION/textIOFF\text{I}_{ON}/\text{I}_{OFF}textION/textIOFF ratio and a lower subthreshold swing. Comparative analysis is carried out using technology computer aided design (TCAD) simulator where the sensitivity of the biosensors has been studied taking into consideration neutral and charged biomolecules for various dielectric constant values. Study of the phenomenon of steric hindrances and probe irregular placements provide better understanding of non-ideal state of the sensors. Due to the structural differences between the biosensors, decreasing step profile exhibits the highest sensitivity for hetero-stacked source TFET biosensor whereas increasing step profile shows the highest sensitivity for heterostructure vertical TFET biosensor. For a particular dielectric constant value of the biomolecule, the vertical based TFET biosensor is 104 times higher in terms of sensitivity as compared to the hetero-stacked source TFET biosensor when considering steric hindrances. Finally, the biosensors are benchmarked against other published literatures and it shows that the sensitivity of the heterostructure vertical TFET biosensor is overall higher than other FET based biosensors.

2021 International Conference on Numerical Simulation of Optoelectronic Devices (NUSOD), 2021

This article reports a highly sensitive and low power photosensor using dual MOSCAP Vertical TFET... more This article reports a highly sensitive and low power photosensor using dual MOSCAP Vertical TFET for near infrared light detection in the wavelength range 0.7µm to 1µm. The optical voltage (VOP) developed because of the photogeneration occurring within the gate region enhances the gate control over the channel and produces higher drain current. The sensitivity is calculated by measuring the alteration of drain current with wavelength. Peak sensitivity of the order of 105 is obtained at VGS=0.5V and provides a maximum responsivity of 1.6x103 A/W at VGS=1.5V for λ= 0.7μm. This modified TFET based hybrid photosensor can be a new generation of highly sensitive photosensor.

Indian Journal of Physics, 2019

This paper explores an analysis of low-and high-frequency noise in a heterojunction, selective bu... more This paper explores an analysis of low-and high-frequency noise in a heterojunction, selective buried oxide (SELBOX) with high-k gate dielectric TFET. The electrical parameters for different doping concentrations, dp ? layer width and mole fractions have been investigated. The proposed structure has been optimized for different positions of small gap on SELBOX substrate. It has been observed that the presence of small gap on SELBOX near the source region provides the lowest OFF current. The variation of noise (flicker ? diffusion ? generation-recombination) with frequency has been analysed. Further, the effect of various noise components on the device performance considering the current noise spectral density (S ID) and voltage noise spectral density (S VG) is investigated. The impact of germanium mole fractions on noise components has been examined in terms of normalized current noise power spectral density and subthreshold swing.

ECS Journal of Solid State Science and Technology, 2020

This paper explores the ferroelectric behavior of silicon doped hafnium oxide incorporated as gat... more This paper explores the ferroelectric behavior of silicon doped hafnium oxide incorporated as gate dielectric in Selective Buried Oxide (SELBOX) TFET. In SELBOX TFET a small gap exists in the buried oxide and the electrical parameters are compared with the ferroelectric SOI TFET. The variation of ferroelectric properties in the presence of different types and thickness of buffer, film thickness has been analyzed. Different electrical parameters such as subthreshold swing (SS) and I ON /I OFF ratio have been investigated for ferroelectric SELBOX TFET and ferroelectric SOI TFET with variations in film thickness. Subthreshold swing of 34 mV/dec has been achieved. Moreover, electrical parameters such as surface potential, electric field and interfacial oxide field have been comprehensively explored to obtain a better insight into the ferroelectric properties of the proposed ferroelectric SELBOX device. The presence of ferroelectric layer enhances the electric field at the tunneling junction which improves the ON current.

Applied Physics A, 2018

This paper explores low-frequency noise analysis of TFET on selective buried oxide (SELBOX) with ... more This paper explores low-frequency noise analysis of TFET on selective buried oxide (SELBOX) with a δp + silicon germanium layer at the source channel junction in the presence of uniform and gaussian trap concentrations. Different electrical parameters of the proposed structure for the optimized position of gap are investigated. Lowest OFF current is obtained for the position of gap near the source region. Considering the current noise spectral density (S ID) and voltage noise spectral density (S VG), the impact of noise on the device performance is analyzed. Noise spectral densities are compared in the presence of interface trap concentrations and δp + Si 1−x Ge x layer Ge-mole fractions. Variation of noise densities with frequency is explored. Improved I ON /I OFF ratio and subthreshold swing are obtained in the presence of uniform trap as compared to gaussian trap.