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This paper proposed, for the first time, that the band-edge effective work functions (EWFs) are achieved by employing PH3 plasma doping (PLAD) TiN metal gate for nMOS device application under replacement metal gate and high dielectric constant (k) dielectric/metal gate last nMOS device. The effects of PLAD energy, dose, gas mixture, and postdoping cleaning procedure on the EWF, EOT, and properties of TiN/HfO2/ILSiO2 gate-stack are investigated; the corresponding possible mechanisms are discussed. Suitable low threshold voltages of nMOSFETs are obtained, while shrinking the EOT. It reduces the corner effect on trench gate doping uniformity, which is induced by shadowing effect in the beam-line implantation technology, to a minimum. It has the potential for the further aggressively scaled 3-D CMOS device and beyond application.

An optimized structure of bulk FinFETs with low punch through leakage is studied by 3D-TCAD simulation. We use an additional gate, called body gate, to control the punch through leakage to achieve low junction leakage. Different body gate bias can be used to control FinFETs punch through leakage without additional dopant in the channel, leading to less random dopant fluctuation. A new process flow to make the bulk FinFET structure with body gate is also proposed.

A probabilistic power flow method considering variable bandwidth kernel density estimation (VKDE) for traction substation loads of high-speed railways is proposed. A variable bandwidth kernel density estimator, which varies the bandwidths to minimize mean squared errors at different estimation points, is adopted to model traction substation loads of high-speed railways. The traction substation loads are sampled by acceptance-rejection method for Monte Carlo probabilistic power flow calculation so that the effects of traction substation loads on power system operation can be effectively analyzed. The effectiveness of the proposed method is illustrated by simulations of practical traction substation loads and the modified IEEE 14-bus system.

To compare the contents of rare earth elements in urine and drinking water of children in the mining and control areas and evaluate the health risk of children in the mining area. Urine and drinking water of 128 children in the mining area and 125 children in the control area were collected from June to July 2015. The contents of rare earth elements were determined using inductively coupled plasma mass spectrometry. The detection rates of rare earth elements, including yttrium (Y), lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), and samarium (Sm), in the urine of children in the exposed group were all 100%, except for samarium (98%); the rates in the control group were 85.7%, 100%, 100%, 98%, 98%, and 59.2%, respectively, and the remaining elements were not detectable. The concentrations of Y, La, Ce, Pr, Nd, and Sm in the urine of children in the exposed group were significantly higher than that in the control group (P

A vertical two-terminal silicon PNPN diode is presented for use in a high-density memory cell. The device design for high-speed operations was studied with experiments and calibrated simulations, which proves that the proposed memory cell can be operated at nanosecond range. The static and dynamic power dissipations were also studied, which indicated the availability of the proposed memory cell for VLSI applications. Moreover, the memory cell is compatible with CMOS process, has little impact from process variation, and has good reliability.

The stability of a graphene field effect transistor (GFET) is important to its performance optimization, and study of hysteresis behavior can propose useful suggestions for GFET fabrication and optimization. In this work, a back-gate GFET has been fabricated and characterized, which is compatible with the CMOS process. The stability of a GFET in air has been studied and it is found that a GFET's electrical performance dramatically changes when exposed to air. The hysteresis characteristic of a GFET depending on time has been observed and analyzed systematically. Hysteresis behavior is reversed at room temperature with the Dirac point positive shifted when the GFET is exposed to air after annealing.