Dual Material Gate SOI MOSFET with a Single Halo

In order to suppress drain-induced barrier lowering in dual material gate SOI MOSFETs,halo doping is used in the channel near the source. Two-dimensional analytical models of surface potential and threshold voltage for the novel SOI MOSFET are developed based on the explicit solution of the two-dimensional Poisson＇s equation. Its characteristic improvement is investigated. It is concluded that the novel structure exhibits better suppression of drain-induced barrier lowering and higher carrier transport efficiency than conventional dual material gate SOI MOSFETs. Its drain-induced barrier lowering decreases with increasing halo doping concentration but does not change monotonically with halo length. The analytical models agree well with the two-dimensional device simulator MEDICI.

A two-dimensional analytical subthreshold behavior model for junctionless dual-material cylindrical surrounding-gate MOSFETs

A two-dimensional analytical subthreshold behavior model for junctionless dual-material cylindrical surrounding- gate （JLDMCSG） metal-oxide-semiconductor field-effect transistors （MOSFETs） is proposed. It is derived by solving the two-dimensional Poisson＇s equation in two continuous cylindrical regions with any simplifying assumption. Using this analytical model, the subthreshold characteristics of JLDMCSG MOSFETs are investigated in terms of channel electro- static potential, horizontal electric field, and subthreshold current. Compared to junctionless single-material cylindrical surrounding-gate MOSFETs, JLDMCSG MOSFETs can effectively suppress short-channel effects and simultaneously im- prove carrier transport efficiency. It is found that the subthreshold current of JLDMCSG MOSFETs can be significantly reduced by adopting both a thin oxide and thin silicon channel. The accuracy of the analytical model is verified by its good agreement with the three-dimensional numerical simulator ISE TCAD.

A two-dimensional analytical model for channel potential and threshold voltage of short channel dual material gate lightly doped drain MOSFET

An analytical model for the channel potential and the threshold voltage of the short channel dual-material-gate lightly doped drain （DMG-LDD） metal-oxide-semiconductor field-effect transistor （MOSFET） is presented using the parabolic approximation method. The proposed model takes into account the effects of the LDD region length, the LDD region doping, the lengths of the gate materials and their respective work functions, along with all the major geometrical parameters of the MOSFET. The impact of the LDD region length, the LDD region doping, and the channel length on the channel potential is studied in detail. Furthermore, the threshold voltage of the device is calculated using the minimum middle channel potential, and the result obtained is compared with the DMG MOSFET threshold voltage to show the improvement in the threshold voltage roll-off. It is shown that the DMG-LDD MOSFET structure alleviates the problem of short channel effects （SCEs） and the drain induced barrier lowering （DIBL） more efficiently. The proposed model is verified by comparing the theoretical results with the simulated data obtained by using the commercially available ATLASTM 2D device simulator.

Subthreshold current model of fully depleted dual material gate SOI MOSFET

Dual material gate SOI MOSFET with asymmetrical halo can suppress short channel effect and increase carriers transport efficiency. The analytical model of its subthreshold drain current is derived based on the explicit solution of two-dimensional Poisson’s equation in the depletion region. The model takes into consideration the channel length modulation effect and the contribution of the back channel current component. Its validation is verified by comparision with two dimensional device simulator MEDICI.

Drain-induced barrier lowering effect for short channel dual material gate 4H silicon carbide metal-semiconductor field-effect transistor

Sub-threshold characteristics of the dual material gate 4H-SiC MESFET （DMGFET） are investigated and the analytical models to describe the drain-induced barrier lowering （DIBL） effect are derived by solving one- and two- dimensional Poisson＇s equations. Using these models, we calculate the bottom potential of the channel and the threshold voltage shift, which characterize the drain-induced barrier lowering （DIBL） effect. The calculated results reveal that the dual material gate （DMG） structure alleviates the deterioration of the threshold voltage and thus suppresses the DIBL effect due to the introduced step function, which originates from the work function difference of the two gate materials when compared with the conventional single material gate metal-semiconductor field-effect transistor （SMGFET）.

Analytical Modeling of Dual Material Gate SOI MOSFET with Asymmetric Halo

A dual material gate silicon-on-insulator MOSFET with asymmetrical halo is presented to improve short channel effect and carder transport efficiency for the first time. The front gate consists of two metal gates with different work functions by making them contacting laterally, and the channel is more heavily doped near the source than in the rest. Using a three-region polynomial potential distribution and a universal boundary condition, a two-dimensional analytical model for the fully depleted silicon-on-insulator MOSFET is developed based on the explicit solution of two-dimensional Poisson＇s equation. The model includes the calculation of potential distribution along the channel and subthreshold current. The performance improvement of the novel silicon-on-insulator MOSFET is examined and compared with the traditional silicon-on-insulator MOSFET using the analytical model and two-dimensional device simulator MEDICI. It is found that the novel silicon-on-insulator MOSFET could not only suppress short channel effect, but also increase cartier transoort efficiency noticeably. The derived analytical model agrees well with MEDICI.

THERMAL-CONDUCTIVITY MEASUREMENTS FOR FILLING MATERIALS FOR SLIDING GATES AND THEIR EFFECTS ON FREE- TAPPING PERFORMANCE OF STEEL LADLE

The thermal conductivities of different typical species filling materials for sliding gate systems for steel ladles were measured using a hot wire technique, and the relationships between thermal conductivity and temperature were regressed. The factors affecting thermal conductivity were analyzed by using variance analysis for a perpendicular experiment. The effects of thermal conductivity on sliding gate free tapping were studied, and it was revealed that decreasing the thermal conductivity of the filling materials is beneficial in enhancing the rate of free tapping for sliding gates.

Price prediction of power transformer materials based on CEEMD and GRU

The rapid growth of the Chinese economy has fueled the expansion of power grids.Power transformers are key equipment in power grid projects,and their price changes have a significant impact on cost control.However,the prices of power transformer materials manifest as nonsmooth and nonlinear sequences.Hence,estimating the acquisition costs of power grid projects is difficult,hindering the normal operation of power engineering construction.To more accurately predict the price of power transformer materials,this study proposes a method based on complementary ensemble empirical mode decomposition(CEEMD)and gated recurrent unit(GRU)network.First,the CEEMD decomposed the price series into multiple intrinsic mode functions(IMFs).Multiple IMFs were clustered to obtain several aggregated sequences based on the sample entropy of each IMF.Then,an empirical wavelet transform(EWT)was applied to the aggregation sequence with a large sample entropy,and the multiple subsequences obtained from the decomposition were predicted by the GRU model.The GRU model was used to directly predict the aggregation sequences with a small sample entropy.In this study,we used authentic historical pricing data for power transformer materials to validate the proposed approach.The empirical findings demonstrated the efficacy of our method across both datasets,with mean absolute percentage errors(MAPEs)of less than 1%and 3%.This approach holds a significant reference value for future research in the field of power transformer material price prediction.

Supplementary Materials: Ultrafast charge transfer in dual graphene-WS_2 van der Waals quadrilayer heterostructures

1. The transient absorption spectra of the WS2 monolayer sample.In the measurement of the transient absorption spectra of the WS2 monolayer sample, A 400-nm (3.1eV) pump pulse with a peak fluence of about 10μJ/cm2excites the electrons from the valence band into the conduction band,the

A curve-based material recognition method in MeV dual-energy X-ray imaging system

High-energy dual-energy X-ray digital radiography imaging is mainly used in the material recognition of cargo inspection. We introduce the development history and principle of the technology and describe the data process flow of our system. The system corrects original data to get a dual-energy transparence image. Material categories of all points in the image are identified by the classification curve,which is related to the X-ray energy spectrum. For the calibration of classification curve, our strategy involves a basic curve calibration and a real-time correction devoted to enhancing the classification accuracy. Image segmentation and denoising methods are applied to smooth the image. The image contains more information after colorization. Some results show that our methods achieve the desired effect.

A two-dimensional analytical modeling for channel potential and threshold voltage of short channel triple material symmetrical gate Stack(TMGS) DG-MOSFET

In the present work, a two-dimensional（2D） analytical framework of triple material symmetrical gate stack（TMGS）DG-MOSFET is presented in order to subdue the short channel effects. A lightly doped channel along with triple material gate having different work functions and symmetrical gate stack structure, showcases substantial betterment in quashing short channel effects to a good extent. The device functioning amends in terms of improved exemption to threshold voltage roll-off, thereby suppressing the short channel effects. The encroachments of respective device arguments on the threshold voltage of the proposed structure are examined in detail. The significant outcomes are compared with the numerical simulation data obtained by using 2D ATLAS;device simulator to affirm and formalize the proposed device structure.

Gamma ray absorption of cylindrical fissile material with dual shields

This work analyzed the gamma ray attenuation effect from the self-absorption and shield attenuation per-spectively. An exact mathematical equation was given for the geometric factor of the cylindrical fissile material with dual shields. In addition, several approximation approaches suitable for real situation were discussed, especially in the radial and axial directions of the cylinders, since the G-factors have simple forms. Then the space distribution patterns of the G-factor were analyzed based on numerical result and effective ways to solve the geometric informa-tion of the cylindrical fissile material, the radii and the heights, were deduced. This method was checked and verified by numerical calculation. Because of the efficiency of the method, it is ideal for application in real situations, such as nuclear safeguards, which demands speed of detection and accuracy of geometric analysis.

Dual Gate液晶显示屏栅极制程断路缺陷的分析与改善

文章探究了光刻工序的水汽和ITO刻蚀工序的药液结晶对DualGate产品栅极制程的断路影响,通过DOE试验得到影响因子的最佳改善条件,使55寸DualGate产品栅极制程的断路缺陷发生率整体降低36%,为公司带来80.2万元的月度收益,能够对其他高端产品断路缺陷的改善思路、新工艺设备的设计改进,提供参考。

Two-dimensional models of threshold voltage and subthreshold current for symmetrical double-material double-gate strained Si MOSFETs

The two-dimensional models for symmetrical double-material double-gate （DM-DG） strained Si （s-Si） metal-oxide semiconductor field effect transistors （MOSFETs） are presented. The surface potential and the surface electric field ex- pressions have been obtained by solving Poisson＇s equation. The models of threshold voltage and subthreshold current are obtained based on the surface potential expression. The surface potential and the surface electric field are compared with those of single-material double-gate （SM-DG） MOSFETs. The effects of different device parameters on the threshold voltage and the subthreshold current are demonstrated. The analytical models give deep insight into the device parameters design. The analytical results obtained from the proposed models show good matching with the simulation results using DESSIS.

A compact two-dimensional analytical model of the electrical characteristics of a triple-material double-gate tunneling FET structure

This paper presents a compact two-dimensional analytical device model of surface potential,in addition to electric field of triple-material double-gate(TMDG)tunnel FET.The TMDG TFET device model is developed using a parabolic approximation method in the channel depletion space and a boundary state of affairs across the drain and source.The TMDG TFET device is used to analyze the electrical performance of the TMDG structure in terms of changes in potential voltage,lateral and vertical electric field.Because the TMDG TFET has a simple compact structure,the surface potential is computationally efficient and,therefore,may be utilized to analyze and characterize the gate-controlled devices.Furthermore,using Kane's model,the current across the drain can be modeled.The graph results achieved from this device model are close to the data collected from the technology computer aided design(TCAD)simulation.

High dielectric constant materials and their application to IC gate stack systems

High dielectric constant (high-k) materials are vital to the nanoelectronic devices. The paper reviews research development of high-k materials, describes a variety of manufacture technologies and discusses the application of the gate stack systems to non-classical device structures.

Dual-gate lateral double-diffused metal—oxide semiconductor with ultra-low specific on-resistance

A new high voltage trench lateral double-diffused metal–oxide semiconductor （LDMOS） with ultra-low specific onresistance （R on,sp ） is proposed. The structure features a dual gate （DG LDMOS）： a planar gate and a trench gate inset in the oxide trench. Firstly, the dual gate can provide a dual conduction channel and reduce R on,sp dramatically. Secondly, the oxide trench in the drift region modulates the electric field distribution and reduces the cell pitch but still can maintain comparable breakdown voltage （BV）. Simulation results show that the cell pitch of the DG LDMOS can be reduced by 50% in comparison with that of conventional LDMOS at the equivalent BV; furthermore, R on,sp of the DG LDMOS can be reduced by 67% due to the smaller cell pitch and the dual gate.

THE BEHAVIOR OF TWO PARALLEL SYMMETRIC PERMEABLE CRACKS IN PIEZOELECTRIC MATERIALS

The behavior of two parallel symmetric cracks in piezoelectric materials under anti-plane shear loading was studied by the Schmidt method for the permeable crack face conditions. By using the Fourier transform, the problem can be solved with two pairs of dual integral equations in which the unknown variable is the jump of the diplacement across the crack surfaces. These equations were solved using the Schmidt method. The results show that the stress and the electric displacement intensity factors of cracks depend on the geometry of the crack. Contrary to the impermeable crack surface condition solution, it is found that the electric displacement intensity factors for the permeable crack surface conditions are much smaller than the results for the impermeable crack surface conditions.

Key technologies for dual high-k and dual metal gate integration

The key technologies for the dual high-k and dual metal gate, such as the electrical optimization of metal insert poly-Si stack structure, the separating of high-k and metal gate of n/pMOS in different regions of the wafer, and the synchronous etching of n/pMOS gate stack, are successfully developed. First, reasonable flat-band voltage and equivalent oxide thickness of pMOS MIPS structure are obtained by further optimizing the HfSiAlON dielectric through incorporating more Al-O dipole at interface between HfSiAlON and bottom SiOx. Then, the separating of high-k and metal gate for n/pMOS is achieved by SC1（NH4OH：H2O2：H2O = 1 ： 1 ： 5） and DHF-based solution for the selective removing of n MOS TaN and Hf Si ON and by BCl3-based plasma and DHF-based solution for the selective removing of pMOS TaN/Mo and HfSiAlON.After that, the synchronous etching of n/pMOS gate stack is developed by utilizing optimized BCl3/SF6/O2/Ar plasma to obtain a vertical profile for TaN and TaN/Mo and by utilizing BCl3/Ar plasma combined with DHF-based solution to achieve high selectivity to Si substrate. Finally, good electrical characteristics of CMOS devices, obtained by utilizing these new developed technologies, further confirm that they are practicable technologies for DHDMG integration.

Non Destructive 3D, 4D Microscopy and Mineral Phase Characterization in Industrial Minerals, Composites to Construction Materials

Conventional electron and optical microscopy techniques require the sample to be sectioned, polished or etched to expose the internal surfaces for imaging. However, such sample preparation techniques have traditionally prevented the observation of the same sample over time, under realistic three-dimensional geometries and in an environment representative of real-world operating conditions. X-ray microscopy (XRM) is a rapidly emerging technique that enables non-destructive evaluation of buried structures within hard to soft materials in 3D, requiring little to no sample preparation. Furthermore in situ and 4D quantification of microstructural evolution under controlled environment as a function of time, temperature, chemistry or stress can be done repeatable on the same sample, using practical specimen sizes ranging from tens of microns to several cm diameter, with achievable imaging resolution from submicron to 50 nm. Many of these studies were reported using XRM in synchrotron beamlines. These include crack propagation on composite and construction materials; corrosion studies; microstructural changes during the setting of cement; flow studies within porous media to mention but a few.