Variation Of Important Parameters Research Articles

In-situ optimization of lateral film uniformity in PVD system by using Fiber Bragg grating temperature sensors

Fiber Bragg grating (FBG) based temperature sensing method has been employed in this work for measuring the lateral temperature distribution on substrate plane during pulse DC magnetron sputtering deposition for optimization of lateral film uniformity. The evolution of temperature distribution with the variation of important process parameters like pulse width (496–1616 ns), deposition pressure (3.1 × 10−3–1.9 × 10–2 mbar) and sputtering power (25–250 W) have been measured over 40 mm radial distance on glass substrate horizon. To investigate the effect of substrate height on the temperature distribution, the later has been measured at two different substrate heights (60 mm and 90 mm) for varying sputtering power. Finally, the effect of variation in temperature distribution on uniformity of thickness and optical, morphological and structural properties have been investigated by separately depositing two HfO2 thin films at two representative extreme deposition powers (75 W and 200 W). The correlation of film non-uniformity of the above properties with the temperature distribution suggests that FBG based multipoint temperature sensing can be possibly used as an indicative tool for in situ optimization of the lateral film uniformity. In addition, the fast response and workability in plasma environment of FBG sensors enables precise in situ mapping of temperature distribution in sputtering process.

Observation of electrical threshold switching behavior and thermal crystallization in bulk Se86-xTe14Snx chalcogenide glasses

Selenium-rich chalcogenides have gained popularity as materials for selector devices due to their unique Ovonic Threshold Switching behavior. Bulk Se86-xTe14Snx glassy alloys (0 ≤ x ≤ 6) were prepared through the traditional melt quenching method. The samples with Sn atomic percentage (x) = 3 to 6 are found to exhibit a rapid and reversible transition between a highly resistive and conductive state affected by an electric field. A remarkable decrement in threshold voltage (Vth) from 453 V to 62 V has been observed with increase in the Tin content. Differential scanning calorimetry (DSC) analysis was carried out to understand the variation of Glass transition temperature (Tg), Crystallization temperature (Tc), and other important glass stability parameters and their compositional dependence. Se82Te14Sn4 sample was found to be thermally most stable with Herby’s parameter value (HR) of 0.3860 and a maximum number of switching cycles at room temperature. X-Ray diffraction patterns of annealed samples were compared with pristine glass to study the multi-phasic Se–Te–Sn alloy. Further, the threshold voltage (Vth) and the number of threshold switching cycles are found to decrease with an increase in temperature till crystallization on-set temperature (Toc). The temperature-dependent conductivity studies showed an abrupt increase in the conductivity of the samples as the temperature crossed the crystallization onset temperature.

Electron-Beam-Induced Carbon Contamination in STEM-in-SEM: Quantification and Mitigation

Abstract Contamination is an undesired side effect in many electron microscopy studies that covers structures of interest and degrades resolution. Although contamination has been studied for decades, open questions remain regarding favorable imaging conditions for contamination minimization and the efficiency of contamination-mitigation strategies. This work focuses on electron-beam-induced carbon contamination in scanning transmission electron microscopy at electron energies of 30 keV and below. A reliable method to measure contamination thicknesses was developed in this work and enables the identification of imaging conditions that minimize contamination. Thin amorphous carbon films were used as test samples. The variation of important imaging parameters shows that the contamination thickness increases with the reduction of the electron energy to about 1 keV but decreases below 1 keV. Contamination increases with the beam current but saturates at high currents. Applying a given dose with a high dose rate reduces contamination. Among the tested contamination-mitigation methods, plasma cleaning and beam showering are most effective. Most experiments in this work were performed with focused scanning illumination. Experiments were also carried out with a stationary defocused beam for comparison with a theoretical contamination model with good agreement between measured and calculated contamination thickness.

Passive Control in Baffled Liquid storage Tank under Bi-directional Earthquakes

A comprehensive study of a 3D baffled concrete liquid storage tank (LST) is conducted to find out the maximum reduction in responses of the LSTs under a set of important parametric variations. They include (i) the type of earthquake; (ii) the optimum position and number of coupled baffles (top-mounted and bottom supported); and (iii) the angle of incidence earthquakes. Further, the percentage reductions of different responses of interest for the optimum baffled LST are investigated. The numerical study is performed in ABAQUS software for a square LST of 6m X 6m X 4.8m having a water height of 3.6m. The response quantities include the maximum mean values of base shear, overturning moment, top board displacement, hydrodynamic pressure, and sloshing height. The results of the study show that (i) with the optimum arrangement of baffles, significant reduction of in the sloshing height can be achieved; (ii) the type of earthquake does not have significant effect response reductions; and (iii) both PGA and angle of incidence of the earthquake have a moderate effect on response reductions.

New quasi-three-, and two-dimensional trigonometric-cubic monomial HSDT for thermal buckling and thermo-mechanical bending analyses of FGM symmetrical/non-symmetrical sandwich plates with hard/soft core

This paper analyses the thermal buckling and thermomechanical bending responses of sandwich plates with FGM face layers, using new quasi-three-, and two-dimensional HSDTs in a unified theoretical formulation. The theory includes both the shear strain illustrated by a new shape function and the stretching effect.The theory makes use of the Hamilton principle to derive the plate governing equations. Then, the Navier procedure solved them for the simply supported boundary conditions. The theory assumed the thermal buckling loads to be uniform, linear, and non-linear distributed through the plate’s thickness, the FGM layers to be isotropically modelled according to a power law and the core layer to be isotropic and homogeneous.After validating the model's analytical solutions with those from the literature (to confirm the model's accuracy), various innovative studies extended the theory. They cover the effects of important parameter variations related to the plate dimensions, material, and the development of the proposed HSDT on the central deflection, stresses, and critical buckling temperature. The theory solutions also present the good performance of the current generalized formulation and the significant influence of the thermal effect. References in the literature can use these findings as foundational data for future research on FGM plates.

A Further Theoretical Study of Capacitive Pressure Sensors Based on Thin Film Elastic Deflection and Parallel Plate Capacitor: Refined Closed-Form Solution and Numerical Calibration.

The capacitive pressure sensor based on thin film elastic deflection and a parallel plate capacitor uses a non-conductive elastic annular thin film centrally connected to a conductive, rigid, flat, concentric-circular thin plate as a pressure sensing unit. On application of pressure, the non-conductive thin film deflects elastically, which in turn moves the conductive thin plate (as a movable upper electrode plate of the parallel plate capacitor) towards the lower electrode plate, resulting in a change in the capacitance of the capacitor. Therefore, the applied pressure can be determined by measuring the capacitance change, based on the closed-form solution for the elastic behavior of the annular thin film under pressure. Such capacitive pressure sensors are more suitable for large-sized sensors such as those used for building-facade wind pressure measurements, etc. In this paper, a further theoretical study of such capacitive pressure sensors is presented. The newly presented, more refined closed-form solution can greatly reduce the output pressure error under the same input capacitance, in comparison with the previously presented closed-form solution. A numerical example of how to use the resulting closed-form solution to numerically calibrate input–output characteristics is given for the first time. The variation trend of pressure operation ranges and input–output characteristics with important parametric variations, which can be used for guiding the design of such capacitive pressure sensors, is investigated.

Experimental study of the transient characteristics of a natural circulation loop under SBLOCA

Abstract In order to understand the influences of various factors on the depressurization rate under small break LOCA occurring at the upper plenum in a natural circulation loop, a basic analysis has been carried out. It is shown that the depressurization rate is influenced by system pressure, back pressure, break area, water mass in the system, heating power, operational state of the second loop, and so on. Experimental results of flow and heat transfer are also presented in this paper. The experiment was carried out at the 5 MW nuclear heating reactor test loop HRTL-5. The transient processes are described and heat transfer coefficients are estimated. The results show that flashing improves the natural circulation and the heat transfer, so the wall temperature of the heated rod can be kept at a lower level and the reactor is safe. The flow oscillation, which leads to cyclical variations of important parameters, is described and its development mechanisms are studied. It is pointed out that the interaction of pressure decreasing and bubbles producing caused by flashing is the main reason of the flow oscillation.

Mitigation of Earthquake Responses Using SMA Supplemented Base-Isolation Devices for Benchmark Building

The efficiency of traditional isolation bearings is doubted for near-field earthquakes because these bearings undergo large displacement. A comparative study of different base isolation systems of base-isolated benchmark building is carried out in the present study. The study is based on assumption that buildings are bi-directionally acted upon by near-field earthquakes for assessing their relative performance in seismic control of the benchmark building. The time history variations of important response parameters and evaluation criteria of the benchmark building has been studied for assessing the effectiveness of the isolation systems. The Shape Memory Alloy (SMA) is utilized with elastomeric bearings and friction bearings to study the effectiveness of SMA wires with different isolators. The benchmark building is modelled as a discrete linear elastic shear structure having three degrees of- freedom at each floor level. Time domain dynamic analysis of this building has been carried out with the help of constant average acceleration Newmark’s method and equilibrium of non-linear forces has been taken care by fourth order Runge-Kutta method. The comparative performance of various isolation systems has been studied with uniform and hybrid combinations. The hybrid combination of SMA supplemented bearings works out the better isolation system keeping in view of the percentage reduction in evaluation criteria for smart base-isolated benchmark building. Furthermore, it is shown that, the functionality of SMA wire is not efficient with Lead Rubber Bearing system, as it is able to control displacement but increases the acceleration, base shear, story drift and isolation forces.

Impact of Hijlan Creek springs on water quality of the Euphrates River and the hydrochemical characterization of the contamination plumes

The aim of this work is to present the hydrochemical mechanisms describing the system of the Euphrates River before and after mixing with groundwater from the springs of Hijlan (western Iraq). Continuously, the data generated from these springs water have been adapted to provide an updated assessment for future water therapeutic purposes. Physicochemical characteristics of water in the mixing plume of Hijlan Creek and Euphrates indicate the multi Hydrochemical plumes as revealed by the spatial variation of important parameters related to the ecological parameters including K+, Na+, Ca2+, Mg2+, HCO3−, SO42−, Cl−, NO3−, PO43−, Pb, Zn, Cd, Fe, Mn, Temp, DO, BOD5, H2S, Turbidity, EC, pH, and TDS. The re-aeration (k2) and de-oxygenation rate (k1) coefficients, as well as the self-purification factor (f) of the mixing plume, are 0.51, 2.03 and 0.25 s−1, respectively. The Cl− concentration in the confluence zone changes, due to the chloride content mixing rates of 7.1 and 92.9% for Euphrates and Hijlan creek water, respectively, with water discharge of 316,224 m3/day and chloride load discharge of 420 tons/day. The assessment of the water quality indicates unsuitability for aquaculture purposes. However, the water can be used for therapeutic purposes and to cure multiple diseases.

New Stable Non-Vector Control Structure for Induction Motor Drive

The article focuses on a design and experimental verification of continuous nonlinear systems control based on a new control structure based on a linear reference model. An application of Lyapunov’s second method ensures its asymptotic stability conditions. The basic idea in the development of the control structure consists of utilizing additional information from a newly introduced state variable. The structure is applied for angular speed control of an induction motor (IM) drive representing a higher-order nonlinear system. The developed control algorithm helps to achieve the zero steady-state control deviation of the IM drive angular speed. Simulations and experiments performed in various operating states of the IM drive confirm the advantages of the new control structure. Except for set dynamics, the method ensures that the system is stable, invariant to disturbances, and is robust against variations of the parameters. When comparing the obtained control structure of the IM control with the classical vector control, the proposed control structure is simpler. In addition, the proposed control structure is linear, robust against variation in important parameters and invariant against external disturbances. The main advantage over conventional control techniques consists of the fact that the controller design does not require any exact knowledge of the system parameters and, moreover, it does not suffer from system stability problems. The method will find a wide applicability not only in the field of AC controlled drives with IM but also generally in control of industry applications.

A physical model for quantum wire infrared photodetectors under illumination condition

In this paper, a theoretical study of quantum wires infrared photodetector (QRIP) under the illumination condition is presented. Here, an analytical approach is developed to calculate the average number of electrons in a quantum wire under illumination condition. Base on the presented formula, a simple mathematical formulation for the QRIP photocurrent is achieved. To show the accuracy of the model, the presented theoretical method is compared with the model reported in the previous literature. Then, QRIP photocurrent behavior over variations of the main important device parameters is investigated.

Reduced soil fauna decomposition in a high background radiation area.

Decomposition of litter and organic matter is a very important soil ecosystem function where soil fauna play an important role. Knowledge of the responses in decomposition and soil fauna to different stressors is therefore crucial. However, the extent to which radioactivity may affect soil fauna is not so well known. There are some results showing effects on soil fauna at uranium mines and near Chernobyl from relatively high levels of anthropogenic radionuclides. We hypothesize that naturally occurring radionuclides affect soil fauna and thus litter decomposition, which will covary with radionuclide levels when accounting for important soil parameters. We have therefore used standardised litterbags with two different mesh sizes filled with birch leaves (Betula pubescens) to assess litter decomposition in an area with enhanced levels of naturally occurring radionuclides in the thorium (232Th) and uranium (238U) decay chains while controlling for variation in important soil parameters like pH, organic matter content, moisture and large grain size. We show that decomposition rate is higher in litterbags with large mesh size compared to litterbags with a fine mesh size that excludes soil fauna. We also find that litter dried at room temperature is decomposed at a faster rate than litter dried in oven (60⁰C). This was surprising given the associated denaturation of proteins and anticipated increased nutritional level but may be explained by the increased stiffness of oven-dried litter. This result is important since different studies often use either oven-dried or room temperature-dried litter. Taking the above into account, we explore statistical models to show large and expected effects of soil parameters but also significant effects on litter decomposition of the naturally occurring radionuclide levels. We use the ERICA tool to estimate total dose rate per coarse litterbag for four different model organisms, and in subsequent different statistical models we identify that the model including the dose rates of a small tube-shape is the best statistical model. In another statistical model including soil parameters and radionuclide distributions, 226Ra (or uranium precursory radionuclides) explain variation in litter decomposition while 228Ra (and precursors) do not. This may hint to chemical toxicity effects of uranium. However, when combining this model with the best model, the resulting simplified model is equal to the tube-shape dose-rate model. There is thus a need for more research on how naturally occurring radionuclides affect soil fauna, but the study at hand show the importance of an ecosystem approach and the ecosystem parameter soil decomposition.

Robustness of Fourier Ptychographic Imaging to Variation of System Parameters

In most optic systems images are captured using a CCD/CMOS sensor, where the phases of the converted photons are inevitably lost. Fourier Ptychographic Microscopy (FPM) circumvents this issue by capturing normal microscopy images, and Fourier transforming them computationally (hence the name). Reconstructing the complex object not only yields amplitude but also phase information, enhanced up to super-resolution. Yet one disadvantage remains unsolved: FPM is a very ill-posed problem, the algorithm is not guaranteed to converge to the correct solution, if it converges at all. In practice this means that there is reasonable doubt if the recovered image actually represents the object under the microscope. This work inquires the quality of FPM reconstruction under variation of important system parameters in simulation and experiment. It shows that the alignment of the illumination source is quite critical: even 0.2 degrees off renders reconstruction useless. This paper thus furthers the costbenefit analysis of which amount of computation time should be spent on digital post-correction.

Analysis and Characterization of Normally-Off Gallium Nitride High Electron Mobility Transistors

High electron mobility transistor (HEMT) based on gallium nitride (GaN) is one of the most promising candidates for the future generation of high frequencies and high-power electronic applications. This research work aims at designing and characterization of enhancement-mode or normally-off GaN HEMT. The impact of variations in gate length, mole concentration, barrier variations and other important design parameters on the performance of normally-off GaN HEMT is thoroughly investigated. An increase in the gate length causes a decrease in the drain current and transconductance, while an increase in drain current and transconductance can be achieved by increasing the concentration of aluminium (Al). For Al mole fractions of 23%, 25%, and 27%, within Al gallium nitride (AlGaN) barrier, the GaN HEMT devices provide a maximum drain current of 347, 408 and 474 mA/μm and a transconductance of 19, 20.2, 21.5 mS/μm, respectively. Whereas, for Al mole fraction of 10% and 15%, within AlGaN buffer, these devices are observed to provide a drain current of 329 and 283 mA/μm, respectively. Furthermore, for a gate length of 2.4, 3.4, and 4.4 μm, the device is observed to exhibit a maximum drain current of 272, 235, and 221 mA/μm and the transconductance of 16.2, 14, and 12.3 mS/μm, respectively. It is established that a maximum drain current of 997 mA/μm can be achieved with an Al concentration of 23%, and the device exhibits a steady drain current with enhanced transconductance. These observations demonstrate tremendous potential for two-dimensional electron gas (2DEG) for securing of the normally-off mode operation. A suitable setting of gate length and other design parameters is critical in preserving the normally-off mode operation while also enhancing the critical performance parameters at the same time. Due to the normally-on depletion-mode nature of GaN HEMT, it is usually not considered as suitable for high power levels, frequencies, and temperature. In such settings, a negative bias is required to enter the blocking condition; however, in the before-mentioned normally-off devices, the negative bias can be avoided and the channel can be depleted without applying a negative bias.

A numerical study on nonlinear bending performance of transversely loaded composite singly curved stiffened surfaces

The review of recent literature shows that the bending performances of transversely loaded laminated composite singly curved stiffened surfaces are not studied in detail using the geometrically nonlinear strains. The present paper aims to fill that void and proposes an isoparametric C° finite element formulation combining von-Karman nonlinearity and Sanders’ first approximation theory. The curved surfaces are simulated using nonlinear strains. The stiffeners are formulated using geometrically linear and nonlinear strains. The correctness of the proposed approach is confirmed through solution of benchmark problems. The relative performances of stiffened curved surfaces in terms of maximum transverse displacements are studied for industrially important parametric variations like boundary conditions, laminations, stacking sequences, and number, orientations, eccentricities, and depth of stiffeners. The results are critically discussed and it is concluded that the clamped 0°/90°/0° shell with curved stiffeners ( y-stiffener) located below the mid-surface shows the greatest bending stiffness. The nonlinear approach is essential for both shell and stiffener for correct prediction of the transverse displacements. The relatively simpler linear approach can be considered for single x-stiffener only.

Breeding ecology of Eurasian bullfinches Pyrrhula pyrrhula in an Iberian hedgerow habitat

ABSTRACT The breeding ecology of the Iberian subspecies of the Eurasian bullfinch, Pyrrhula pyrrhula iberiae, is addressed for the first time. The studied population occupied a hedgerow habitat in northwestern Spain. Individuals directly watched in the study area and details of these sightings were recorded over a six-year period, and a total of 56 nests were monitored. The earliest date of nest building was within 11–30 April for all years. Fledglings were recorded leaving the nest during all the ten-day periods from the end of May to mid-August. Nest attendance, from the early building stage to when nestlings were ready to leave the nest, lasted approximately 36 days. The overall mean clutch size was 4.56 eggs. Clutch size decreased significantly at the end of the breeding season. For all egg traits, the minimum values for standard deviation were obtained in the intra-clutch analysis, and egg length was more variable than width. Nesting success increased progressively from April–May to June–July and August. The main proximate cause of nest failure was egg desertion/predation, followed by nest desertion during nest building and nestling desertion/predation. Mammals were the main agents in nests where the probable predator could be identified. Approximately half of the eggs became fledglings leaving the nest, no significant seasonal differences being observed for this parameter. In August, the ratio of juveniles to adults was 2.5–4.1, juveniles representing approximately 70–80% of the individuals seen and identified that month. The absence of significant interannual variation in important reproductive parameters could have been due to lack of interannual variation in the availability of food resources. Compared to other subspecies, mean clutch size of Iberian bullfinches is the smallest recorded in the western Palearctic, and they showed an earlier start to the breeding season and shorter mean egg length than North European and Russian populations.

Parametric sensitivity analysis for a natural gas fueled high temperature tubular solid oxide fuel cell

For more than the last two decades, there has been research going on to develop advanced energy technologies involving minimum environmental pollution, to replace the conventional fossil energy systems. Solid oxide fuel cells (SOFCs) are one of the most promising, eco-friendly and efficient means for the generation of electricity to meet the future energy requirements. This research work focuses on the parametric sensitivity analysis for natural gas fueled high temperature tubular SOFC. Firstly, for the tubular SOFC, a one-dimensional radially symmetrical model has been developed and solved using the finite-difference method. Then, the effect of the variation of important operational and design parameters on its performance has been analyzed. The parameters typically include composition, inlet fuel temperature, pressure, length of SOFC tube and thicknesses of its components. The composition is expressed as steam to methane ratio and it has been observed that the voltage and power density developed by the SOFC diminishes as the ratio increases. Further, a change in the inlet fuel pressure of the tubular SOFC has no pronounced influence on the voltage and power density developed. On the other hand, with an increase in the inlet fuel temperature, a small improvement in these performance characteristics is exhibited. The axial length of the tubular SOFC does conspicuously influence its performance characteristics but solely at current densities greater than 4000A/m2. An increase in the thickness of its components results in a reduction in its voltage and power density developed. The largest decline in these performance characteristics with the increase in thickness is observed for electrolyte followed by cathode and anode respectively.

Numerical study of the flow structure at a swash tip propagating over a rough bed

Understanding the boundary layer flow structure at the tip of a swash flow is important for improving predictions of wave run-up, coastal flooding and sediment transport processes on beaches, but this is difficult to investigate experimentally. Recently, there has been debate regarding the mechanics of boundary layer growth during the uprush flow. Here, an extensively validated RANS model is used to investigate the swash tip dynamics during a dam-break driven swash event. The model enables the analysis of the spatial and temporal variation of important parameters, in particular the water surface gradients, the bed shear stress, and the non-uniformity of the velocity profile. The rate of flow convergence of surface particles toward the tip, and the ratio of the depth-averaged flow velocity and celerity of the swash tip are also obtained. The flow depth varies with distance behind the wave tip approximately as a power law, with a power of 1/2–3/4. The surface elevation dips offshore at distances greater than 0.2 m behind the front. The shear stress decreases quite slowly in the spatial region immediately behind the wave tip, and is in very good agreement with the flat-plate boundary layer model of Barnes and Baldock (2010). The model results indicate that the boundary layer structure is well-developed or depth-limited at the wave tip, and fits a power-law velocity profile with an exponent of order 1/3, consistent with a rough bed. The normalised vertical variation in the velocity profile is very uniform in the region 1 m behind the wave tip, and matches that for a 1/3 power law. Alternate logarithmic fits to the velocity profile yield consistent values of bed roughness at different locations, but corresponding to a grain size that is about twice that used in the experiment. The rate of flow convergence of surface particles toward the wave tip is also consistent with a fully developed boundary layer and a 1/3 power law.

Influence of systematic variations of the stimulation profile on responses evoked with a vestibular implant prototype in humans

Objective. To explore the impact of different electrical stimulation profiles in human recipients of the Geneva-Maastricht vestibular implant prototypes. Approach. Four implanted patients were recruited for this study. We investigated the relative efficacy of systematic variations of the electrical stimulus profile (phase duration, pulse rate, baseline level, modulation depth) in evoking vestibulo-ocular (eVOR) and perceptual responses. Main results. Shorter phase durations and, to a lesser extent, slower pulse rates allowed maximizing the electrical dynamic range available for eliciting a wider range of intensities of vestibular percepts. When either the phase duration or the pulse rate was held constant, current modulation depth was the factor that had the most significant impact on peak velocity of the eVOR. Significance. Our results identified important parametric variations that influence the measured responses. Furthermore, we observed that not all vestibular pathways seem equally sensitive to the electrical stimulus when the electrodes are placed in the semicircular canals and monopolar stimulation is used. This opens the door to evaluating new stimulation strategies for a vestibular implant, and suggests the possibility of selectively activating one vestibular pathway or the other in order to optimize rehabilitation outcomes.

Optimization and Comparison of Drift Region Specific ON-Resistance for Vertical Power Hk MOSFETs and SJ MOSFETs With Identical Aspect Ratio

This article proposes a MATLAB-based optimization methodology of the drift region specific ON-resistance ( ${R}_{on,sp}$ ) both for the high-permittivity ( $\text{H}{k}$ ) MOSFETs and superjunction (SJ) MOSFETs with design parameters expressed by breakdown voltage (BV) and aspect ratio (AR). The optimized method has three distinctive features. First, based on the built-in functions in MATLAB, the proposed method is very efficient to accurately obtain the optimized ${R}_{on,sp}$ ( ${R}_{on,sp(opt)}$ ) and the design parameters for both MOSFETs. Second, as the reflection of the process difficulty in the $\text{H}{k}$ or SJ structure, AR is used as one of the design variables. Third, the cubic polynomial functions are used to obtain a more accurate fitting for the optimization. The optimized results demonstrate that for a given BV, the ${R}_{on,sp(opt)}$ for the SJ MOSFET decreases as AR increases, whereas an optimum AR exists for a minimal ${R}_{on,sp(opt)}$ for the $\text{H}{k}$ MOSFET. Extensive comparisons demonstrate that when AR is small and BV is large, the ${R}_{on,sp(opt)}$ for the $\text{H}{k}$ MOSFET could be lower than that for the SJ MOSFET. Parameter designs are performed for the 900-V $\text{H}{k}$ MOSFET and SJ MOSFET. The impacts of important parameter variations on BV and ${R}_{on,sp}$ are also discussed. The validity of the proposed optimization method is demonstrated by the TCAD simulations.