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The subthreshold swing (SS) of a field-effect transistor (FET) is given by the body factor multiplied by the transport factor and has a limit of 60 mV ⋅ dec−1 at room temperature in the case of the MOSFET. To break this SS limit, the negative-capacitance FET (NC-FET) lowers the body factor by using a ferroelectric film in the gate stack, whereas the cold source FET (CS-FET) and the Dirac source FET (DS-FET) lower the transport factor by introducing an electronic bandgap or manipulating the density of states in the injecting source. In this work, we theoretically and computationally investigate the possibility of FETs with both NC and CS/DS so that both the body and transport factors are lowered simultaneously. The new device physics of the negative-capacitance CS-FET (NCCS-FET) is numerically investigated for 2-D monolayer black phosphorus (ML-BP) FETs with the Hf0.5Zr0.5O3 ferroelectric material in the gate stack. The device characteristics of six different FETs, the conventional MOSFET, CS-FET, DS-FET, NC-FET, NCCS-FET, and NCDS-FET are calculated and compared. Overall, the NCCS-FET achieves an average SS of 30.1 mV ⋅ dec−1 and a minimum SS as low as 7.21 mV⋅ dec−1; its ON–OFF ratio is about four orders of magnitude higher than that of a conventional MOSFET. The combined effects of NC and CS more efficiently decrease power dissipation. [ABSTRACT FROM AUTHOR]

This paper presents a novel Galerkin-type method of moments solution of the volume surface integral equation (VSIE), which is developed for the analysis of electromagnetic scattering and radiation from composite metallic and dielectric structures. Our new scheme utilizes curved tetrahedral elements and curved triangular patches for geometric modeling, and the associated higher order hierarchical vector (HOHV) basis functions for volume/surface current modeling. In contrast to the previous studies on higher order VSIE, our scheme, which is reported for the first time in VSIE, is much more flexible. In comparison with the conventional low-order scheme, our scheme requires much less memory and computational time for the same accuracy level. Numerical results are provided to demonstrate the accuracy, efficiency, and flexibility of our scheme. [ABSTRACT FROM PUBLISHER]

In this brief, a physical model describing the scattering of holes in the channel of SiGe p-MOSFET caused by roughness and charged defects at/near the high-κ dielectric/SiO2 interface is proposed. Using the Fang-Howard's variational wave function, the hole mobility is calculated with consideration of the above two scattering mechanisms. The effects of device parameters such as the thicknesses and permittivities of the high-κ dielectric and interlayer on the hole mobility are discussed. [ABSTRACT FROM AUTHOR]

Dependences of magnetoresistance and morphology upon the insertion of very thin magnetic layers at interfaces between magnetic and nonmagnetic layers in Co/Cu and Ni/sub 81/Fe/sub 19//Cu multilayers have been investigated. The Co/Cu multilayers with inserted Fe thickness of 0.5/spl sim/1.0 /spl Aring/ have the MR ratio of about 18% more than the noninserted multilayers, and the MR ratio in the NiFe/Cu multilayers with inserted Co of thickness of 3 /spl Aring/ was found to be significantly increased. These results can be explained by the enhanced interlayer antiferromagnetic coupling and spin-dependent scattering phenomena at the interface. Of particular interest, the "Clustered out-growth" in the surface morphology of these multilayers was observed. [ABSTRACT FROM PUBLISHER]