High Transport Si/SiGe Heterostructures for CMOS Transistors with Orientation and Strain Enhanced Mobility

OH, Jungwoo,HUANG, Jeff,OK, Injo,LEE, Se-Hoon,D. KIRSCH, Paul,JAMMY, Raj,LEE, Hi-Deok The Institute of Electronics, Information and Comm 2011 IEICE transactions on electronics Vol.94e.c No.5

<P>We have demonstrated high mobility MOS transistors on high quality epitaxial SiGe films selectively grown on Si (100) substrates. The hole mobility enhancement afforded intrinsically by the SiGe channel (60%) is further increased by an optimized Si cap (40%) process, resulting in a combined ∼100% enhancement over Si channels. Surface orientation, channel direction, and uniaxial strain technologies for SiGe channels CMOS further enhance transistor performances. On a (110) surface, the hole mobility of SiGe pMOS is greater on a (110) surface than on a (100) surface. Both electron and hole mobility on SiGe (110) surfaces are further enhanced in a <110> channel direction with appropriate uniaxial channel strain. We finally address low drive current issue of Ge-based nMOSFET. The poor electron transport property is primarily attributed to the intrinsically low density of state and high conductivity effective masses. Results are supported by interface trap density (D<SUB>it</SUB>) and specific contact resistivity (<I>ρ<SUB>c</SUB></I>).</P>

Load-carrying capacities and failure modes of scaffold-shoring systems, Part II: An analytical model and its closed-form solution

Huang, Y.L.,Kao, Y.G.,Rosowsky, D.V. Techno-Press 2000 Structural Engineering and Mechanics, An Int'l Jou Vol.10 No.1

Critical loads and load-carrying capacities for steel scaffolds used as shoring systems were compared using computational and experimental methods in Part I of this paper. In that paper, a simple 2-D model was established for use in evaluating the structural behavior of scaffold-shoring systems. This 2-D model was derived using an incremental finite element analysis (FEA) of a typical complete scaffold-shoring system. Although the simplified model is only two-dimensional, it predicts the critical loads and failure modes of the complete system. The objective of this paper is to present a closed-form solution to the 2-D model. To simplify the analysis, a simpler model was first established to replace the 2-D model. Then, a closed-form solution for the critical loads and failure modes based on this simplified model were derived using a bifurcation (eigenvalue) approach to the elastic-buckling problem. In this closed-form equation, the critical loads are shown to be function of the number of stories, material properties, and section properties of the scaffolds. The critical loads and failure modes obtained from the analytical (closed-form) solution were compared with the results from the 2-D model. The comparisons show that the critical loads from the analytical solution (simplified model) closely match the results from the more complex model, and that the predicted failure modes are nearly identical.

The Bandgap Structure and the Transfer Behavior of 1-D Dielectric Photonic Crystals with Magnetic Defect Layers

M. D. Huang,이영백,이주열,K. W. Kim,P. J. Kim,S. Y. Park,Y. H. Lu 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.49 No.5I

This work concerns the optical properties of not only 1-D photonic crystals (PCs) on a glass substrate, consisting of dielectric Ti2O3 and Al2O3, but also 1-D magnetic PCs of Bi:YIG thin layers added to the 1-D PCs. The structure of the pure dielectric multilayers was optimized, and the omni-photonic bandgap (PBG) properties were investigated. When a Bi:YIG layer with an optical thickness of ¸/2 is inserted, a defect mode is obtained at the designed wavelength within the PBG. However, if the thickness is ¸/4, no defect mode is observed. More magnetic defect layers produce correspondingly more defect modes. The existence of magnetic layers leads to a considerable amount of coupled light, perpendicular to the polarization direction of the linearly-polarized incident light, revealing a large magneto-optical eect, which is related to localized photon states at the defect modes within the PBG. The intensity of coupled light is found to be easily aected by absorption in the magnetic layers.

Vertical coherence functions of wind forces and influences on wind-induced responses of a high-rise building with section varying along height

D.M. Huang,L.D. Zhu,W. Chen,Q.S. Ding 한국풍공학회 2015 Wind and Structures, An International Journal (WAS Vol.21 No.2

The characteristics of the coherence functions of X axial, Y axial, and RZ axial (i.e., body axis) wind forces on the Shanghai World Trade Centre - a 492 m super-tall building with section varying along height are studied via a synchronous multi-pressure measurement of the rigid model in wind tunnel simulating of the turbulent, and the corresponding mathematical expressions are proposed there from. The investigations show that the mathematical expressions of coherence functions in across-wind and torsional-wind directions can be constructed by superimposition of a modified exponential decay function and a peak function caused by turbulent flow and vortex shedding respectively, while that in along-wind direction need only be constructed by the former, similar to that of wind speed. Moreover, an inductive analysis method is proposed to summarize the fitted parameters of the wind force coherence functions of every two measurement levels of altitudes. The comparisons of the first three order generalized force spectra show that the proposed mathematical expressions accord with the experimental results well. Later, the influences of coherence functions on wind-induced dynamic responses are analyzed in detail based on the proposed mathematical expressions and the frequency-domain method of random vibration theory.

Power spectra of wind forces on a high-rise building with section varying along height

D.M. Huang,L.D. Zhu,W. Chen 한국풍공학회 2014 한국풍공학회지 Vol.18 No.3

The characteristics of amplitudes and power spectra of X axial, Y axial, and RZ axial (i.e., body axis) wind forces on a 492 m high-rise building with a section varying along height in typical wind directions are studied via a rigid model wind tunnel test of pressure measurement. Then the corresponding mathematical expressions of power spectra of X axial (across-wind), Y axial (along-wind) and torsional wind forces in 315o wind directions are proposed. The investigation shows that the mathematical expressions of wind force spectra of the main structure in across-wind and torsional directions can be constructed by the superimposition of an modified wind spectrum function and a peak function caused by turbulent flow and vortex shedding, respectively. While that in along-wind direction can only be constructed by the former and is similar to wind spectrum. Moreover, the fitted parameters of the wind load spectra of each measurement level of altitude are summarized, and the unified parametric results are obtained. The comparisons of the first three order generalized force spectra show that the proposed mathematical expressions accord with the experimental results well.

Effect of Dietary Copper Sources (Cupric Sulfate and Cupric Methionate) and Concentrations on Performance and Fecal Characteristics in Growing Pigs

Huang, Y.,Zhou, T.X.,Lee, J.H.,Jang, H.D.,Park, J.C.,Kim, I.H. Asian Australasian Association of Animal Productio 2010 Animal Bioscience Vol.23 No.6

This study was conducted to assess the effects of organic and inorganic copper on performance in growing pigs. A total of 100 pigs, average age 63 d and initial body weight 21.46${\pm}$1.13 kg, were assigned to five treatment groups. Dietary treatments included i) CON (basal diet, 0 ppm Cu), ii) T1 (basal diet with 67 ppm Cu as cupric sulfate, $CuSO_4$), iii) T2 (basal diet with 134 ppm Cu as $CuSO_4$), iv) T3 (basal diet with 67 ppm Cu as cupric methionate, CuMet) and v) T4 (basal diet with 134 ppm Cu as CuMet). Throughout the entire experimental period, ADG (average daily gain), ADFI (average daily feed intake) and G/F (gain: feed) ratios showed no significant differences. The dry matter digestibility was improved in the T1, T2, T3, and T4 treatments (p<0.05), as compared with CON. Nitrogen digestibility was improved in the T3 treatment group as compared with CON (p<0.05). As compared with the T1 treatment group, fecal pH values were improved in the CON, T3, and T4 treatment groups (p<0.05). Fecal Cu concentrations were significantly lower in the CON, T3, and T4 treatment groups than in T1 and T2 (p<0.05). The incidence of diarrhea was reduced when the pigs were fed on the T2, T3, and T4 diets as compared with CON. In conclusion, diets supplemented with 67 or 134 ppm Cu as CuMet may prove effective in improving nutrient digestibility and fecal pH value in growing pigs, and fecal Cu concentrations may be reduced by CuMet supplementation.

Load-carrying capacities and failure modes of scaffold-shoring systems, Part I: Modeling and experiments

Huang, Y.L.,Chen, H.J.,Rosowsky, D.V.,Kao, Y.G. Techno-Press 2000 Structural Engineering and Mechanics, An Int'l Jou Vol.10 No.1

This paper proposes a simple numerical model for use in a finite analysis (FEA) of scaffold-shoring systems. The structural model consists of a single set of multiple-story scaffolds with constraints in the out-of-plane direction at every connection joint between stories. Although this model has only two dimensions (termed the 2-D model), it is derived from the analysis of a complete scaffold-shoring system and represents the structural behavior of a complete three-dimensional system. Experimental testing of scaffolds up to three stories in height conducted in the laboratory, along with an outdoor test of a five-story scaffold system, were used to validate the 2-D model. Both failure modes and critical loads were compared. In the comparison of failure modes, the computational results agree very well with the test results. However, in the comparison of critical loads, computational results were consistently somewhat greater than test results. The decreasing trends of critical loads with number of stories in both the test and simulation results were similar. After investigations to explain the differences between the computationally and experimentally determined critical loads, it was recommended that the 2-D model be used as the numerical model in subsequent analysis. In addition, the computational critical loads were calibrated and revised in accordance with the experimental critical loads, and the revised critical loads were then used as load-carrying capacities for scaffold-shoring systems for any number of stories. Finally, a simple procedure is suggested for determining load-carrying capacities of scaffold-shoring systems of heights other than those considered in this study.

Vertical coherence functions of wind forces and influences on wind-induced responses of a high-rise building with section varying along height

Huang, D.M.,Zhu, L.D.,Chen, W.,Ding, Q.S. Techno-Press 2015 Wind and Structures, An International Journal (WAS Vol.21 No.2

The characteristics of the coherence functions of X axial, Y axial, and RZ axial (i.e., body axis) wind forces on the Shanghai World Trade Centre - a 492 m super-tall building with section varying along height are studied via a synchronous multi-pressure measurement of the rigid model in wind tunnel simulating of the turbulent, and the corresponding mathematical expressions are proposed there from. The investigations show that the mathematical expressions of coherence functions in across-wind and torsional-wind directions can be constructed by superimposition of a modified exponential decay function and a peak function caused by turbulent flow and vortex shedding respectively, while that in along-wind direction need only be constructed by the former, similar to that of wind speed. Moreover, an inductive analysis method is proposed to summarize the fitted parameters of the wind force coherence functions of every two measurement levels of altitudes. The comparisons of the first three order generalized force spectra show that the proposed mathematical expressions accord with the experimental results well. Later, the influences of coherence functions on wind-induced dynamic responses are analyzed in detail based on the proposed mathematical expressions and the frequency-domain method of random vibration theory.

Four-dimensional calibration turntable of the motional Stark effect diagnostic on EAST

Huang, X.,Liu, D. M.,Liu, C.,Fu, J.,Wan, B. N.,Lyu, B.,Wu, Z. W.,Holcomb, C. T.,Ko, J.,Rowan, W. L.,Huang, H.,Miao, G. Z. American Institute of Physics 2018 Review of scientific instruments Vol.89 No.10

Probing two-dimensional metallic-like and localization effects at low magnetic fields

Huang, T.Y.,Liang, C.T.,Kim, G.H.,Huang, C.F.,Huang, C.P.,Ritchie, D.A. North-Holland 2010 Physica E, Low-dimensional systems & nanostructure Vol.42 No.4

The metallic-like regime characterized by Shubnikov-de Haas (SdH) oscillations is investigated between localization-induced weak insulator and quantum Hall liquid in a gated two-dimensional GaAs electron system containing InAs dots. Multiple SdH crossing points are observed in the longitudinal resistivity before the appearance of the critical point of a plateau transition with increasing perpendicular magnetic field. In conductivities, however, there is no corresponding crossing in the metallic-like regime because of the T-dependent Hall slope under electron-electron interaction, which provides an explicit way to distinguish SdH crossing points from the critical point in our study.