Kinetics of electroless Ni-Cu-P deposits on silicon in a basic hypophosphite-type bath

Eleetroless Ni-Cu-P deposits were deposited on the Si substrate in a basic hypophosphite-type plating bath.The effects ofpH value and the metal source composition, Ni and Cu, in the plating bath on the kinetics of the Ni-Cu-P deposition were studied.The electroless Ni-Cu-P deposits were characterized by a scanning electron microscope, a transmission electron microscope, an en-ergy dispersive X-ray spectroscope, and an X-ray diffractometer.The results showed that the pH value of the plating bath had no ob- vious effect on the morphology and composition of electroless Ni-Cu-P deposits.However, the composition of the metal source, Ni and Cu, in the plating bath had great effect on the kinetics of electroless Ni-Cu-P deposition.     

Antagonistic responses between magnetoconductance and magnetoelectroluminescence in polymer light-emitting diodes

Antagonistic responses between magnetoconductance (MC) and magnetoelectroluminescence (MEL) in the polymer light-emitting diodes with an interfacial layer between Al cathode and active layer are simultaneously measured. As the interfacial layer (tetraoctylammonium bromide) is used, the significant increase in the number of injected negative polarons and the blocking of positive polarons promote the triplets-(free polaron) reaction and provide a good explanation for the reason that electroluminescence (EL) efficiency is maximal in the trap free space charge limited current regime at high bias. By fitting of MC and MEL curves using Lorentzian and non-Lorentzian empirical equations, three magnetic field dependent mechanisms, which are the intersystem crossing between singlet/triplet polaron pairs, the triplets-(free polaron) reaction, and the triplets-(trapped polaron) reaction are elucidated. The distribution of the three components is tunable by varying the applied electric field, which primarily modulates the triplets-(free polaron) reaction rate. The results pave a new route toward understanding the mechanism of organic spintronics for developing of multifunctional devices.     

Deposition and Clearance Models of Ni Compounds in the Mouse Lung and Comparisons with the Rat Models

Experimental data from inhalation studies in mice were used to develop mathematical models of deposition, clearance, and retention kinetics in the respiratory tract for inhaled Ni compounds (high temperature (green) NiO,Ni₃S₂, and NiSO₄.6H₂O) in the mouse lung. For deposition, a new model was developed using the experimental data on nasal deposition and lung morphometry by Phalen (1991). Three major mechanisms of airway deposition, including impaction, sedimentation, and diffusion, were considered in the deposition model. Because of the differences in physiological and ventilation conditions, it was found that mice have a lower alveolar deposition fraction than rats when exposed to the same Ni compounds. In the development of a clearance model, a single compartment model in the lung was used and a general assumption was made that the clearance of the insoluble and moderately soluble Ni compounds (high temperature (green) NiO and Ni₃S₂, respectively) depends highly on the volume of retained particles in the lungs. As for the highly soluble Ni compound (NiSO₄.6H₂O), the clearance rate coefficient was assumed to depend on the retained particle mass and total alveolar surface. The retention half time, however, was found to increase with the lung burden for high temperature (green) NiO and NiSO₄.6H₂O particles, but to decrease with the lung burden for Ni₃S₂ particles. The retention half times for high temperature (green) NiO and Ni₃S₂ particles in mice are shorter than in rats, whereas the retention half time for NiSO₄.6H₂O particles is the same for both species.     

Improvement in oxide thickness uniformity by repeated spikeoxidation

A new repeated spike oxidation (RSO) method used in a rapid thermal processing system was proposed in this work. Simulation results predict the temperature distribution on the wafer would be improved by this RSO method. We proposed that the improvement in wafer temperature uniformity is mainly caused by self-compensation in radiation heat absorption rate. Experimental data pointed out that the new method can produce more uniform oxide thickness than the conventional one under an intentionally created nonuniform heating environment     

Improving the efficiency of Monte Carlo power estimation [VLSI]

In this paper, we propose two efficient statistical sampling techniques for estimating the total power consumption of large hierarchical circuits. We first show that, due to the characteristic of the sampling efficiency in Monte Carlo simulation, granularity of samples is an important issue in achieving high overall efficiency. The proposed techniques perform sampling both temporally (across different clock cycles) and spatially (across different modules) so that a smaller sample granularity can be achieved while maintaining the normality of samples. The first proposed technique, which is referred to as the module-based approach, samples each module independently when forming a power sample. The second technique, which is referred to as the cluster-based approach, lumps the modules of a hierarchical circuit into a number of clusters on which sampling is then performed. Both techniques adapt stratification to further improve the efficiency. Experimental results show that these techniques provide a reduction of 23× in simulation run time compared to existing Monte-Carlo simulation techniques     

A study of liquefaction related damages on shield tunnels

Studies of liquefaction-related damages on underground structures are limited and sometimes controversial. Liquefaction potential analysis is essential in tunnel design in liquefiable soils. A Taipei Rapid Transit System (TRTS) tunnel site in Taipei County was selected to study the risk under liquefaction-related damage. The liquefaction risk index was applied for assessment of the overall liquefaction risks and liquefaction-induced settlement at the interest site. The anti-liquefaction measure for shield tunneling by using secondary injection grouting was discussed to eliminate the flow of liquefied soils and reduce the liquefaction-induced settlement.     

Is Educational Intervention Research on the Decline?

The authors examined intervention studies that appeared in 4 educational psychology journals (Cognition & Instruction, Contemporary Educational Psychology, Journal of Educational Psychology, Journal of Experimental Education) and the American Educational Research Journal (AERJ) in 1983 and from 1995 to 2004. The majority of studies included adults (age 18 and older) as participants, administered brief (less than 1 day) interventions, assessed intervention effects immediately following the intervention, and did not report treatment integrity. Most studies included multiple outcome measures and exhibited an increase in effect-size reporting from 4% in 1995 to 61% in 2004. The percentage of total articles based on randomized experiments decreased over the 21-year period in both the educational psychology journals (from 40% in 1983 to 34% in 1995 to 26% in 2004) and AERJ (from 33% to 17% to 4%). Limitations of the study and future research issues are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Three-dimensional artifact induced by projection weighting andmisalignment

In recent years, the use of computer graphic techniques to produce three-dimensional (3-D) and reformatted images from a set of axial computed tomography (CT) images has gained significant interest. In most cases, the CT images are generated with the projection data set weighted prior to reconstruction, to combat motion artifacts, data inconsistency, or redundant data samples. In this paper, we investigate the potential bias introduced to the reconstruction as a result of the interaction of the projection weights and the isocenter misalignment (ISM). We demonstrate that when the weights applied to the conjugate rays are significantly different, bias will result which favors the sample with a higher weight. Although the error is not easily detected in axial CT images, it can be quite visible in 3-D or multiplanar reformatted (MPR) images. In this paper, we first present a theoretical framework to analyze and predict the bias. The theoretical prediction is validated by both computer simulations and phantom experiments. Several schemes to combat this artifact are subsequently presented; and their effectiveness is demonstrated.