Analysis of Subthreshold Swing of Symmetric Junctionless Double Gate MOSFET Using Gaussian Doping Profile

—The variation of subthreshold swing(SS) according to the projected range (Rp ) and standard projected deviation (σp ) was analyzed when the symmetrical junctionless double gate (JLDG) MOSFET was doped with Gaussian doping profile. For this purpose, the analytical SS model was presented. We compared with the TCAD results to turn out the validity of this model, and the SSs of this model agreed with those of TCAD. The effective conduction path and mean doping concentration affecting the SS were analyzed according to the Rp and σp . As a result, the SS increased as the Rp and σp increased simultaneously. The smaller the Rp and the larger the σp , the lower the SS. When Rp = 1.5 nm, it showed the SS below 100mV/dec without being affected by the change of σp or silicon thickness. When σp = 3nm, it was also 100mV/dec or less regardless of the change of Rp and silicon thickness. Keywords— Double gate, Junctionless, Subthreshold swing, Gaussian, Projected range, Standard projected deviation

Functional Properties of Donor (Al) and Acceptor (Cu) Codoped High Dielectric Constant ZnO Nanoparticles

In this work, we have synthesized donor-acceptor (Al-Cu) codoped ZnO nanoparticles with a doping concentration of 0%, 0.25%, 0.5%, and 0.75% by coprecipitation method. The synthesized samples were then annealed at 350°C and 600°C. All the samples showed wurtzite structure of ZnO with no secondary phase. The increase in doping concentration led to deterioration of crystalline quality, while improved crystallinity was observed at higher annealing temperature. The morphological study of these samples showed good grain-to-grain contact with less isolated pores. These samples were further characterized by impedance spectroscopy for analyzing dielectric properties. The values of the real part of dielectric constant and tangent loss showed decreasing trend with frequency. The appearance of semicircular arcs in the impedance complex plane plots indicates contribution of grains and grain boundaries and presence of different relaxation processes. 0.5% Al and Cu codoped ZnO showed the best dielectric response with a high value of dielectric constant and low tangent loss.

Analysis of InN/La2O3 Twosome for Double-Gate MOSFETs for Radio Frequency Applications

The channel material of a gate describes the operating condition of the MOSFET. A suitable operating condition prevails in MOSFETs if the transistors are quite enough to observe and control at the nanometer regime. An efficient gate and channel material have been proposed in this work which is based on the electrical properties they exhibit at the temperature of 300K. The doping concentration for the electrons and holes is maintained to be 1Χ1019cm-3 for the entire electronic simulator. The simulation results show that using La2O3 along with Indium Nitride (InN) material for the designing of Double-Gate (DG) MOSFETs provides better controllability over the transistor at a channel length of 50nm. This proposed DG-MOSFET is more compliant than the conventional coplanar MOSFETs based on Silicon.

Comparative Investigation on Micro-Structural, Morphological, Optical, Magnetic and Anti-Microbial Traits of Undoped and Nickel-Incorporated Zinc Oxide Nanoparticles

The main objective of the present work is to synthesize pure and nickel doped zinc oxide nanoparticles by facile co precipitation technique. The work is confined to study the effect of various weight ratios (0.3, 0.6 ,0.9) % Nickel into Zinc oxide and to witness the drastic changes that occur in its various physical properties such as structural, optical, magnetic from X ray diffraction (XRD), UV visible (ultra violet) spectra, VSM (Vibrating sample magneto meter). XRD analysis reveals the wurtzite hexagonal structure and it is also found that as the doping concentration increases the crystallite size decreases from 4.6 nm to 3.0 nm. SEM results depicts the agglomeration of the particle, the synthesized samples shows both rod and flakes formation when the doping concentration is increased. Morphological changes were analysed TEM (Transmission electron microscope). The enhancement in the optical behaviour were observed and the energy band gap is calculated with the data obtained from UV-Visible spectra and the optical properties shows a tremendous increase as the Ni content increases which proves the sample a suitable candidate for solar cells and photovoltaic devices. Purity of the prepared sample were investigated through EDAX analysis. The hysteresis loop from the VSM analysis elucidate the saturation magnetization and the ferromagnetic behaviour of the sample. X-ray Photoemission Spectroscopy results indicates the presence of several oxygen species adsorbed on the surface. The study is also extended to analyse its anti-microbial effect against Staphylococcus aureus. The cell culture dish of the sample showed a notable resistance against Staphylococcus aureus when the concentration of nickel is increased and could be extended to pharmaceutical applications in treating several skin infections.

Effect of Doping Concentration on Grain Boundary Conductivity of Samaria Doped Ceria Composites

This work aims to study the effect of Sm3+ doping concentration on the grain boundary ionic conductivity of ceria. The materials were prepared by a modified co-precipitation method, where molecular water associated with the precursor has been utilized to facilitate the hydroxylation process. The synthesized hydroxide / hydrated oxide materials were calcined and the green body (pellet) has been sintered at high temperature in order to achieve highly dense (~ 96 %) pellet. The structural analyses were done using XRD and Raman spectroscopy, which confirm the single phase cubic structure of samaria doped ceria (SDC) nanoparticles and the surface morphology of sintered samples was studied using FESEM. The ionic conductivity was measured by AC impedance spectroscopy of the sintered pellets in the temperature range of 400-700 °C, which shows superior grain boundary conductivity. The grain boundary ionic conductivity of around 0.111 S/cm has been obtained for 15SDC composition at 600 °C.

Variation between Antiferromagnetism and Ferrimagnetism in NiPS3 by Electron Doping

How to electrically control magnetic properties of a magnetic material is promising towards spintronic applications, where the investigation of carrier doping effects on antiferromagnetic (AFM) materials remains challenging due to their zero net magnetization. In this work, we found electron doping dependent variation of magnetic orders of a two-dimensional (2D) AFM insulator NiPS3, where doping concentration is tuned by intercalating various organic cations into the van der Waals gaps of NiPS3 without introduction of defects and impurity phases. The doped NiPS3 shows an AFM-ferrimagnetic (FIM) transition at doping level of 0.2-0.5 electrons/cell and a FIM-AFM transition at doping level of ≥0.6 electrons/cell. We propose that the found phenomenon is due to competition between Stoner exchange dominated inter-chain ferromagnetic order and super-exchange dominated inter-chain AFM order at different doping level. Our studies provide a viable way to exploit correlation between electronic structures and magnetic properties of 2D magnetic materials for realization of magnetoelectric effect.

Absorption efficiency analysis and optical resonator simulation of Ho:YLF laser pumped with Tm:fiber laser

In this paper, a Tm:fiber laser pumped Ho:YLF laser is simulated. The absorption efficiency, optimum crystal length, and optical resonator are analytically studied and simulated using LASCAD software, and the atomic-level degeneracies are considered in evaluating the absorption efficiency. In this way, the absorption efficiencies of 65% and 87% are obtained for single-pass 30 mm Ho:YLF crystal with doping concentration 0.5% and 1% respectively. These calculated efficiencies are verified by our experimental measurements and they coincide with acceptable errors. To estimate a proper length for the Ho:YLF crystal with specified doping concentration, the up-conversion, and the reabsorption effects are considered. As a result, we find the 30 mm length crystal is suited for reducing the absorption threshold and prohibiting reabsorption while saturation is controlled. The threshold power and slope efficiency for 65 W pumped powers are calculated by LASCAD software, and the thermal lens focal length of −665 mm is obtained. For a nearly constant beam width inside the cavity and suitable beam overlap efficiency, a concave-concave configuration is chosen for the optical resonator. In the continuous-wave operation, the output power is funded to be 38.4 W and the slope efficiency would be 66%.