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The lower efficiency of a Photoconductive Antenna is a significant bottleneck in using them for several applications. This manuscript presents a solution to improve the photoconductive antenna performance using the nano-dot structures in the electrode's gap. This study analyses the nano-dots' shape, size, and spacing effects on the current pulse and the frequency response of a normal photoconductive antenna. For the analysis, square, hexagonal, and circular shape dots are considered with different sizes and spacing. The optimization study shows that not all combinations enhance photoconductive antenna performance using the above-defined dots. The circular dot photoconductive antenna produces an enhancement of 63.16 and 166.2% in the current pulse amplitude and radiated power, respectively, using different combinations of nano-dot size and gap. The frequency response analysis shows that the circular dot photoconductive antenna produces highest directivity (8.76 dBi) among all the nano-dot geometries. [ABSTRACT FROM AUTHOR]

A detailed Sentaurus TCAD simulation based study for Silicon Double Gate Tunnel Field Effect Transistor (Si-DG TFET) based Ring Oscillator (RO) is presented in this work. Two different ring oscillator topologies (simple RO and Negative Skewed Delay RO)are presented with two different structures for TFET device. The two structures are different in the source-drain extension regions widths. The extension region width variation effects are studied and presented for inverter and ring oscillator. A TFET based inverter is presented to show the changes in behavior due to variations in the drain extension region widths, which is later used for RO designs. The drain extension region width changes the drain extension region resistances which in turn is responsible for change in the corresponding device properties. RO simulation are used for calculating the delay. To further explore digital and analog applications transfer characteristics and noise margins of inverter are explored with power supplies variations. Better reliability for oscillation frequency is obtained using Negative Skewed Delay ring oscillator (NSD RO) topology. NSD RO is resulting in lesser jitter, more reliable frequency as compared to single-ended ring oscillator topology. By tuning the supply voltage of the device the ring oscillator frequency can be used for RF applications, thus it works like a voltage controlled oscillator (VCO). [ABSTRACT FROM AUTHOR]

In this work, a 2 − D analytical model of Dielectrically Modulated, Dual Material, Double Gate Junctionless MOSFET (DMDG-JL-MOSFET) based label free biosensor has been proposed to investigate the effect of high-κ gate dielectric materials (TiO2, HfO2, and Al2O3) and cavity length variation on the sensitivity of the biosensor. The model has been validated with data obtained from Sentaurus TCAD simulator. The variation in threshold voltage (Vth), drain current (Id) and ION/IOFF ratio has been used as the sensing metric to estimate the sensitivity of the proposed biosensor. It has been observed that at a cavity length (Lcav) of 25 nm, TiO2 shows 87%, 68% and 52% higher sensitivity than if SiO2 is taken as gate dielectric in case of neutral, positively charged and negatively charged biomolecules respectively. Further, the effectiveness of the proposed DMDG-JL-MOSFET based biosensor is confirmed by benchmarking the sensitivity metric with contemporary architectures of JL-MOSFET based biosensor. We have reported that DMDG-JL-MOSFET exhibits significant increase in sensitivity when compared to other contemporary JL-MOSFET based biosensors, thus making the proposed device an attractive solution for biosensing applications. [ABSTRACT FROM AUTHOR]

Ag/ITO/MoOx/n-Si/LiFx/Al carrier-selective contact (CSC) solar cell structures are modelled and numerically simulated based on the experimental data using an industrial quality base silicon wafer by the Sentaurus TCAD software. The role of (1) electron-selective lithium fluoride (LiFx) layer and its thickness, (2) hole-selective molybdenum oxide (MoOx) work function variation, and (3) front contact (MoOx/n-Si) surface passivation interlayer are explored on the device performance. The electron-selective LiFx layer at the rear side is led to the substantial enhancement in device photocurrent by providing the electrical barrier to the minority carriers (holes) and a slight improvement in open-circuit voltage, but the thickness of the layer is sensitive to efficient extraction of the majority carriers (electrons). The hole-selective MoOx layer work function needs to be engineered for inducing the strong inversion layer with better built-in potential at the MoOx/n-Si junction to achieve high open-circuit voltage from a cell. A thin SiOx interlayer at the MoOx/n-Si junction has significantly enhanced the device's open-circuit voltage by minimizing the minority carrier recombination at the interface. [ABSTRACT FROM AUTHOR]

In this paper, an extensive investigation of low-frequency (1/f) noise and total ionizing dose–response of junctionless accumulation mode double-gate (JAM DG) MOSFET is presented. Current–voltage (Id–Vg) characteristics and low-frequency noise of JAM DG MOSFET are simulated at different ionized doses and compared to different gate oxide thickness and different channel doping concentrations. A significant amount of irradiation-induced threshold voltage shift and increase in low-frequency noise is observed for different gate oxide thickness and channel doping concentration. Moreover, the irradiation-induced border trap densities are also obtained at different doses. The gamma radiation model of Sentaurus TCAD is used to get the required results. [ABSTRACT FROM AUTHOR]

In this work, the impact of gate material work function on the sensitivity of dual-material, double-gate, junctionless MOSFET ( D M D G - J L - M O S F E T )-based biosensor has been studied. To enhance the sensitivity of the biosensor, optimization of gate work functions has been done through Sentaurus TCAD simulator. With the immobilization of biomolecules in the cavity at different value of work function of gate metal 1 (M1) and gate metal 2 (M2), i.e., WF1 and WF2, enhancement in sensing metrics (change in threshold voltage S V th and I ON / I OFF ratio) is observed. The enhancement in sensitivity is profound in source-side gate (M1) work function (WF1) optimization as compared to drain-side gate (M2) work function (WF2) optimization. Sensitivity of 90 mV is observed in source-side gate work function optimization which is ∼ 89% more than the sensitivity of 23 mV which is achieved in drain-side gate work function optimization for a fixed concentration and dielectric constant of biomolecules. It has also been noted that the proposed structure exhibits ∼ 90 % higher sensitivity than the single-material, dual-gate, junctionless MOSFET ( S M D G - J L - M O S F E T ) biosensor. Results showcase that the optimization of gate metal work functions enhances the sensitivity of the biosensor. [ABSTRACT FROM AUTHOR]

The optimum absorbing-layer thickness in the bottom In0.3Ga0.7As subcell of a triple-junction In0.3Ga0.7As/GaAs/In0.5Ga0.5P solar cell is sought for using the Sentaurus TCAD software package as a factor of the minority charge-carrier lifetime in this layer. The lifetime is set in the range from 17 ps to 53 ns. The calculation results show that the optimum thickness varies from 0.9 to 7.5 μm. In addition, the contribution of the bottom In0.3Ga0.7As subcell to the efficiency of this triple-junction solar cell is estimated at various lifetime values. Its value varies from 1 to 7%. [ABSTRACT FROM AUTHOR]

Stress-engineered fin-shaped field effect transistors (FinFET) using germanium (Ge) is a promising performance booster to replace silicon (Si) due to its high holes mobility. This paper presents a three-dimensional simulation by the Sentaurus technology computer-aided design to study the effects of stressors--channel stress, stress-relaxed buffer (SRB), and source/drain (S/D) epitaxial stress--on different bases of FinFET, specifically silicon germanium (SiGe) and Ge-based, whereby the latter is achieved by manipulating the Ge mole fraction inside the three layers; their effects on the devices' figures-ofmerits were recorded. The simulation generates an advanced calibration process, by which the drift diffusion simulation was adopted for ballistic transport effects. The results show that current enhancement in p-type Fin- FET (p-FinFET) with 110% is almost twice that in n-type FinFET (n-FinFET) with 57%, with increasing strain inside the channel suggesting that the use of strain is more effective for holes. In SiGe-based n-FinFET, the use of a highstrained SRB layer can improve the drive current up to 112%, while the highstrain S/D epitaxial for Ge-based p-FinFET can enhance the on-state current to 262%. Further investigations show that the channel and S/D doping are affecting the performances of SiGe-based FinFET with similar importance. It is observed that doping concentrations play an important role in threshold voltage adjustment as well as in drive current and subthreshold leakage improvements. [ABSTRACT FROM AUTHOR]

The influence of the doping concentration in the active layer and in the bulk substrate on the drain current of a silicon-on-insulator (SOI) field-effect Hall sensor (FEHS) using Sentaurus TCAD is studied. At the initial stage, the numerical model is corrected by comparing the transfer current-voltage characteristics of the calculation and the experimentally measured SOI FEHS sample. It is shown that, under low concentrations in the active layer, the drain current depends on the capacity of the front gate, while the doping concentration in the bulk substrate affects the drain current only when the device is operating in depletion mode. [ABSTRACT FROM AUTHOR]