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Since the CALUX (Chemically Activated LUciferase gene eXpression) bioassay is a fast and inexpensive tool for the throughput analysis of dioxin-like compounds in a large number of samples and requires only small sample volumes, the use of this technique in human biomonitoring programs provides a good alternative to GC-HRMS. In this study, a method for the separate analysis of PCDD/Fs and dioxin-like PCBs (dl-PCBs) in human serum with the new sensitive H1L7.5c1 mouse hepatoma cell line was optimized. Sample dilution factors of 5 and 2.4 were selected for routine analysis of respectively the PCDD/Fs and dl-PCBs. The validation studies showed that repeatability and within-lab reproducibility for the quality control (QC) standard were within the in-house criteria. A long-term within-lab reproducibility of 25% for the PCDD/F fraction and 41% for the dl-PCB fraction for the analysis of pooled serum samples, expressed as pg BEQ/g fat, was determined. CALUX recoveries of the spiked procedural blanks were within the acceptable in-house limits of 80-120% for both fractions and the LOQ was 30.3 pg BEQ/g fat for the PCDD/Fs and 14.5 pg BEQ/g fat for the dl-PCBs. The GC-HRMS recovery of a C13-spiked pooled serum sample was between 60 and 90% for all PCDD/F congeners and between 67 and 82% for the non-ortho PCBs. An adequate separation between both fractions was found. The CALUX/GC-HRMS ratio for a pooled serum sample was respectively 2.0 and 1.4 for the PCDD/Fs and the dl-PCBs, indicating the presence of additional AhR active compounds. As expected, a correlation was found between human serum samples analyzed with both the new H1L7.5c1 cell line and the more established H1L6.1c3 cell line. The geometric mean CALUX-BEQ values, reported for the adolescents of the second Flemish Environment and Health Study (FLEHS II) recruited in 2009-2010, were 108 (95% CI: 101-114) pg CALUX-BEQ/g fat for the PCDD/Fs and 32.1 (30.1-34.2) pg CALUX-BEQ/g fat for the dioxin-like PCBs.

Metallization options to fill 30nm ½ pitch trenches have been explored and their Time-Dependent-Dielectric-Breakdown (TDDB) and electromigration (EM) performance have been benchmarked to the conventional PVD TaNTa / PVD Cu seed based metallization. CVD Co as seed enhancement layer shows no deterioration in TDDB performance and improved EM performance, but the activation energy for EM was 0.68±0.20eV, which is at the lower end of the expected value of 0.85–0.95eV for this parameter. PVD RuTa barriers with 90%Ru and 10%Ta show degraded barrier performance and significant lowering of activation energy for EM (0.59±0.05eV). Finally, it is shown that, using an optimized PVD Cu seed, standard PVD TaNTa-barriers give excellent TDDB performance and that typical EM lifetime specs can be met with this metallization scheme down to 30nm ½ pitch.

Using a dedicated test vehicle (low-k planar capacitor) for studying the intrinsic properties of low-k materials and using standard single damascene 50 and 90nm ½pitch test vehicles, differences in reliability behavior between intrinsic and integrated SiOCH porous low-k materials were investigated. The studied parameters were leakage current, breakdown field, distributional shape of failure times and TDDB lifetimes. Compared to the intrinsic material, the integrated properties significantly deteriorated and these differences were quantified. The low-k planar capacitor test vehicle was also used to study the intrinsic breakdown behavior at low fields. Using statistical simulations, we found that the proper choice of high field conditions is crucial to be able to discriminate between different lifetime models at low fields and recommendations are given on how to choose these high field conditions. Based on tests of several months, the E- and 1/E-model can be excluded (all test material had a standard TaNTa barrier between copper and dielectric). The √E-model and the power law are statistically not different, but a strong tendency towards the power law is observed. As a corollary, we compared the benefit of choosing less conservative lifetime models for extrapolations to lower fields to the loss that occurs when predicting median failure times to lower percentiles. We show that process optimizations leading to a lower spread in the failure times are more important than choosing less conservative lifetime models.

A test structure that allows the study of void formation kinetics during electromigration is proposed and characterized. Compared to a standard single-via electromigration test structure voltage-senses are placed near the via. This allows monitoring resistance changes before final void formation, while the void formation process is not affected. Part of the samples show single void formation, while for other samples, multiple voids are formed. For the single void case, a model is proposed to calculate void-depth as a function of time. Initially, voids grow faster and this growth slows down towards the end of the void formation process. Estimated velocities during void formation are in the same order of magnitude compared to literature results of drift velocities during void growth. Cases where multiple voids are formed show that voids which initially form further away from the via stop growing upon formation of a void closer to the via.

Renormalization group recursions based on mean-field approximations [J. O. Indekeu, A. Maritan, and A. L. Stella, J. Phys.A15, L291 (1982)], commonly referred to as mean-field renormalization group methods (MFRG), have proven to be efficient and easily applicable for computing non-classical critical properties of lattice models. We give a fairly complete bibliography of applications to date, and extend previous test calculations of bulk, surface, and corner critical exponents in the two-dimensional Ising model to larger cluster sizes on triangular, square (including crossing bonds), and honeycomb lattices. Without much effort the exact value of the critical exponent ratioyH/yT is reproduced systematically with a precision of 2%. This ratio turns out to be the most accurate probe of non-classical critical behaviour that is available in the MFRG method.

Extremely low field time dependent dielectric breakdown measurements were performed on single damascene structures with 90 and 50nm ½pitch integrated in a porous low-k material (k=2.5). We found with statistical significance that the E-model and the √E-model were too conservative to extrapolate our high field data to these low fields. Also, while soft breakdown does not occur at higher fields and wider spacings, we demonstrate that the time difference between soft and hard breakdown becomes significant in the 50nm ½pitch structures at normal operating fields. Besides this, we detected a change in distributional shape at these low fields and we argue that an extrinsic failure mode could be driving these failures or that the role of spacing variations across the wafer becomes more significant at lower fields.

A review of existing work on the integration of a rotating mechanical Cu sensor is given and the measurement system shown as an alternative technique to those which require advanced facilities. As analytical models are unable to fully describe the structure, a model based on the large strain finite element method was used to describe the operation of structure. Excellent agreement between simulations and experimental data is shown over a large data set. Furthermore, the extracted stress is comparable to measurements performed using high intensity x‐ray diffraction on similar samples. Finally, it is shown the sensor can be used to study the impact of Cu post plating anneals on stress evolution in the scaled structure. This work demonstrates the rotating sensor as a viable tool for future characterization of interconnect structures.

The influence of residual vacancy concentrations and stress gradients on electromigration both in the metal layer below and above copper via's with a diameter of 90nm integrated in low-k materials has been investigated. Variations in stress gradients and vacancy concentrations were created by applying different post-plating anneal conditions. The impact of these variations was quantified based on high temperature storage tests both at the optimum stress-induced-voiding temperature and around the copper stress free temperature. By linking the results from these high temperature storage tests to electromigration data, we observe residual vacancy concentrations contribute more to upstream electromigration, while downstream electromigration is more vulnerable to residual stress gradients.

New technologies for manufacturing 3D Stacked ICs offer numerous opportunities for the design of complex and effcient embedded systems. But these technologies also introduce many design options at system/chip design level, hard to grasp during the complete design cycle. Because of the sequential nature of current design practices, designers are often forced to introduce design margins to meet required specications, resulting in sub-optimal designs. In this paper we introduce new design methodology and practical tool chain, called PathFinding Flow, that can help designers to easily trade-off between different system level design choices, physical design and/or technology options and understand their impact on typical design parameters such as cost, performance and power. Proposed methodology and the tool chain will be demonstrated on a practical case study, involving fairly complex Multi-Processor System-on-Chip using Network-on-Chip for communication medium. With this example we will show how High-Level Synthesis can be used to quickly move from high-level to RTL models, necessary for accurate physical prototyping for both computation and communication. We will also show how the possibility of design iteration, through the mechanism of feedback based on physical information from physical prototyping, can improve design performance. Finally, we will show how we can move in no time from traditional 2D to 3D design and how we can measure benets of such design choice.

The time and temperature dependence of Stress-Induced-Voiding below and in copper VIA's with a diameter of 80nm integrated in a k=2.5 material was studied. The focus was on the early phase of the voiding process. To accelerate the degradation, test structures with big metal plates below and/or above the VIA were used. We found two degradation mechanisms in which one dominated below and the other dominated above a certain temperature. The first mechanism has an activation energy of 0.9eV and is the result of interface-diffusion driven by a stress-gradient. This mechanism was more pronounced below the VIA, but was significant in the VIA as well. The second mechanism has an activation energy of 1.2eV, which is argued to be driven by grain boundary diffusion due to a vacancy gradient in and above the VIA. To explain both mechanisms, an addition to the traditional stress-creep model is proposed and fits our data well. Additionally, it is discussed that VIA's connected to the center of big metal plates above and below the VIA are less susceptible to SIV compared to VIA's connected to line ends either below or on top of the VIA. We support our argumentation and analytical modeling with Finite Element Modeling.

As dielectric spacing between adjacent copper wires scales below 50nm, back-end-of-line dielectric reliability is becoming an increasingly important challenge both for advanced logic and memory devices. It is crucial to understand which physical mechanisms are relevant, because this has an impact on modeling and prediction. In this contribution test methods, test structures and physical mechanisms are discussed.

The degradation and breakdown mechanisms of a SiOCH low-k material with k = 2.3 (25% porosity) and thicknesses ranging from 90 nm to 20 nm were investigated. By combining the time dependent dielectric breakdown data at positive/negative bias stress with the thickness scaling results, dielectric failure is proven to be intrinsic and not influenced by copper drift or metal barrier deposition induced dielectric damage. It is shown that stress induced leakage current (SILC) can be used as a measure of dielectric degradation. Therefore, low field lifetimes can be safely estimated using SILC extrapolation. Based on our results, both the impact damage model and the power law model have a good accuracy for low field lifetime prediction. Recovery and anneal experiments are used to study the physical nature causing the observed negative flatband voltage shifts in our metal-insulator-semiconductor planar capacitor structures, where hydrogen induced unstable fast and slow donor type interface states are hypothesized to be the root cause of the observed shifts. We suggest that atomic hydrogen is released from the dielectric during electron injection and migrates to the interfacial region. Our model is further supported by an observed irreversible SILC change during the recovery and anneal studies. The degradation mechanism proposed in this work, supported by the low field lifetime data, provides a feasible explanation for intrinsic low-k dielectric failure.

Until recently, only a compiler and a high-level simulator of the reconfigurable architecture ADRES existed. This paper focuses on the problems that needed to be solved when moving from a software-only view on the architecture to a real hardware implementation, as well as on the verification process of all involved tools.

Eleven cyanopropyl ("cyano") columns were characterized by means of a relationship developed originally for alkyl-silica columns. Compared to type-B alkyl-silica columns (i.e., made from pure silica), cyano columns are much less hydrophobic (smaller H), less sterically restricted (smaller S*), and have lower hydrogen-bond acidity (smaller A). Because sample retention is generally much weaker on cyano versus other columns (e.g., C8, C18), a change to a cyano column usually requires a significantly weaker mobile phase in order to maintain comparable values of k for both columns. For this reason, practical comparisons of selectivity between cyano and other columns (i.e., involving different mobile phases for each column) must take into account possible changes in separation due to the change in mobile phase, as well as change in the column.

As reported previously, five solute-column interactions (hydrophobicity, steric resistance, hydrogen-bond acidity and basicity, ionic interaction) quantitatively describe column selectivity for 163 alkyl-silica, polar-group and cyano columns. In the present study, solute retention and column selectivity for 11 phenyl and 5 fluoro-substituted columns were compared with alkyl-silica columns of similar ligand length. It is concluded that two additional solute-column interactions may be significant in affecting retention and selectivity for the latter columns: (a) dispersion interactions of varying strength as a result of significant differences in bonded-phase polarizability or refractive index and (b) pi-pi interactions in the case of phenyl columns and aromatic solutes. These 16 phenyl and fluoro columns were also characterized in terms of hydrophobicity, steric resistance, hydrogen-bond acidity and basicity, and ionic interaction.

In the field of high temperature electronics some doubts have been expressed about the validity of the Arrhenius relation. In this paper the in-situ electrical measurement technique is presented to investigate the temperature dependence of failure mechanisms and conduction mechanisms of several material systems in a broad temperature region. Measurement results will be presented showing single-activation energy and multiple-activation energy behaviour of a.o. electrical conduction, degradation of resistances, electromigration and time dependent dielectric breakdown at high temperature conditions.

We report a case of a woman hospitalized after chloroquine overdose whose whole blood concentration on admission was 7.87 micrograms/ml. High blood concentrations of chloroquine induce cardiotoxicity and have been associated with death when they exceed 3.0 micrograms/ml. Early administration of massive doses of diazepam has been described to reduce the mortality due to chloroquine toxicity, but the protective mechanism has remained unknown. This patient was treated with diazepam (2.0 mg/kg over 30 min followed by a dosage of 1.0 to 2.0 mg/kg over 24 h), yet she remained awake despite the high plasma concentrations of diazepam and nordiazepam which would normally be associated with sedation. This suggests an antagonistic effect of chloroquine on the benzodiazepine-induced sedation due to an interaction between these drugs at their site of action.

In-situ electromigration tests have been performed inside a scanning electron microscope on 30 nm wide single damascene interconnects without vias, where a good resolution was obtained and drift velocities during void growth could be measured at 300 °C. These tests showed direct evidence that the cathode end of the line, where a polycrystalline grain cluster encounters a bigger grain, can act as a flux divergent point of Cu diffusion. Moreover, it was found that a thicker barrier suppresses barrier/interface diffusivity of Cu atoms, thereby slowing down electromigration-induced void growth. It was also demonstrated that Cobalt based metal caps are beneficial to electromigration for advanced interconnects where thinner barriers are required.

Since the invention of the integrated circuit (IC) in 1959, there has been an enormous growth in performance and complexity of electronic systems by drastically reducing the basic building blocks and increasing the circuit density. Due to this ongoing miniaturization of microelectronics, new physical mechanisms can be triggered or known physical mechanisms can be enhanced inducing ageing and failure of the electronic material systems. The time evolution of these ageing mechanisms has to be understood in order to guarantee the lifetime of several years required for products such as personal computers, automobiles, home appliances etc. The study of failure mechanisms in electronic components requires a combination of advanced electrical, analytical and statistical tools.

Synthetic 3-methyl-branched chain fatty acids were used to decipher the breakdown of phytanic acid. Based on results obtained in intact or permeabilized rat hepatocytes, rat liver homogenates or subcellular fractions, a revised alpha-oxidation pathway is proposed which appears to be functioning in man as well. In a first step, the 3-methyl-branched chain fatty acid is activated by an acyl-CoA synthetase. This reaction requires CoA, ATP and Mg2+. Subsequently, the acyl-CoA ester is hydroxylated at position 2 by a peroxisomal dioxygenase. This step is dependent on alpha-oxoglutarate, ascorbate (or glutathione), Fe2+ and O2. The 2-hydroxy-3-methylacyl-CoA intermediate is cleaved by a peroxisomal lyase to formyl-CoA and a 2-methyl-branched fatty aldehyde. Formyl-CoA is (partly enzymically) hydrolyzed to formate, which is then converted, most likely in the cytosol, to CO2. In the presence of NAD+, the aldehyde is dehydrogenated to a 2-methyl-branched fatty acid, presumably by a peroxisomal aldehyde dehydrogenase. This acid can--after activation--be degraded via a D-specific peroxisomal beta-oxidation system.

The stereochemistry of the alpha-oxidation of 3-methyl-branched fatty acids was studied in rat liver. R- and S-3-methylhexadecanoic acid were equally well alpha-oxidized in intact hepatocytes and homogenates. Subcellular fractionation studies showed that alpha-oxidation of both isomers is confined to peroxisomes. Dehydrogenation of 2-methylpentadecanal, the end-product of the peroxisomal alpha-oxidation of 3-methylhexadecanoic acid, to 2-methylpentadecanoic acid, followed by derivatization with R-1-phenylethylamine and subsequent separation of the stereoisomers by gas chromatography, revealed that the configuration of the methyl-branch is preserved throughout the whole alpha-oxidation process. Metabolism and formation of the 2-hydroxy-3-methylhexadecanoyl-CoA intermediate were also investigated. Separation of the methyl esters of the four isomers of 2-hydroxy-3-methylhexadecanoic acid was achieved by gas chromatography after derivatization of the hydroxy group with R-2-methoxy-2-trifluoromethylphenylacetic acid chloride and the absolute configuration of the four isomers was determined. Although purified peroxisomes are capable of metabolizing all four isomers of 2-hydroxy-3-methylhexadecanoyl-CoA, they can only form the (2S,3R) and the (2R,3S) isomers. Our experiments exclude the racemization of the 3-methyl branch during the alpha-oxidation process. The configuration of the 3-methyl branch does not influence the rate of alpha-oxidation, but determines the side of the 2-hydroxylation, hence the configuration of the 2-hydroxy-3-methylacyl-CoA intermediates formed during the process.

Matisse is a design flow intended for developing embedded systems characterize dby tight inter action b etwe encontrol and data-flow behavior, intensive data storage and tr ansfer, dynamic creation of data, and stringent real-time requirements. Matisse bridges the gap from a system specification, using a cocurr ent obje ct-oriented language, to an optimize d embedded single-chip HW/SW implementation. Matisse supp orts stepwise system-level exploration and refinement, memory architecture exploration, and gradualincorporation of timing constr aints b efore going to tr aditional tools for HW synthesis, SW compilation, and HW/SW interprocessor communication synthesis. Application of Matisse on telecom protocol processing systems shows significant improvements in area usage and power c onsumption.

The electrical conduction of a SiCOH based ultralow-k (k = 2.0) dielectric is investigated over an electric field range from 1.0 MV/cm to breakdown. Below 4.0 MV/cm, space-charge-limited current dominates the leakage. Above 5.0 MV/cm, a transition is found from trap-assisted Fowler-Nordheim (F-N) tunneling to F-N tunneling. It is hypothesized that under F-N tunneling stress, intrinsic material degradation causes positively charged defects generated in the dielectric. Moreover, this change of the dominant conduction path has a significant impact on the time dependent dielectric breakdown lifetime behavior. © 2013 AIP Publishing LLC. ispartof: Applied Physics Letters vol:103 issue:3 status: published

A simple high-performance liquid chromatographic assay for the measurement of quinine, hydroxychloroquine, chloroquine, and desethylchloroquine in small volumes (50-200 microL) of serum, whole blood, or filter paper-adsorbed dry blood was developed. The analytes are isolated by liquid-liquid extraction and chromatographed on a sulfophenylpropyl-modified silica column under isocratic conditions. The column effluent is monitored by fluorimetry (excitation wavelength, 215 nm; no emission filter). The limit of quantitation is 0.005-0.01 mg/L for chloroquine and hydroxychloroquine and 0.05 mg/L for quinine. No interference from other antimalarial drugs or other compounds commonly used has been observed. Quantitative results can be obtained within 1 hour of receipt of the sample.

An HPLC method for the quantitation of paraquat in urine was applied to serum. Sample preparation consisted of ion-pair extraction on disposable cartridges of end-capped octadecyl silica. The paraquat thus extracted, was quantitated by HPLC using 1,1'-diethyl-4,4'-dipyridyl dichloride as an internal standard. Relatively small sample volumes (1 mL serum) were required. Within- and between-assay coefficients of variation for the HPLC technique were 2.9% and 4.0%, respectively, at low paraquat serum concentration (0.4 microgram/mL), and 2.4% and 3.2% at high paraquat serum concentration (4.0 micrograms/mL). The between-assay coefficient of variation for the total procedure, including the extraction, was 5.6% at low concentration (0.4 microgram/mL). Serum concentration levels down to 0.025 microgram/mL could be quantitated. The technique was checked for interference from muscle relaxants (pancuronium bromide and vecuronium bromide) and from anticoagulants (heparin and K2EDTA). No interference was observed.

CAMELEON is a symbolic layout system, suited for industrial designs, that delivers layouts that can be compared with (orthogonal) manual layouts. This is obtained by: (1) a technology description language (TDL) describing layout primitives and design rules, which allows the customization of the system to any technology; (2) the ability to handle complex primitives, like S- or L-shaped transistors, allowing dense packing of diffusion blocks; and (3) considering compaction as a basic operation in the creation of stick diagrams. The designer can control compaction and is provided with adequate feedback. The conditions to obtain automatic technology conversions are discussed. The compaction method is explained extensively, in particular the partitioning and the covering method, used to increase time performance. A fast circuit-extraction module makes the link to simulation and verification tools. Some basic electrical rules are also checked. >

Summary. Six hundred new samples are added to those we previously reported from the Shungura and Usno Formations of southwestern Ethiopia, and the entire data set is reviewed. Limited mineralogical study of sands indicates maghemite and hematite as carriers of remanence. After AF cleaning the remanent directions are well polarized into normal and reversed groups, with greater scatter in reversed directions. The time-averaged magnetization axis corresponds to a ‘far-sided right-hand’ virtual pole, a pattern previously found by Wilson. Intrasite dispersion is commonly large but better for the new samples, which we attribute to field technique. Polarity zonation is accomplished by statistical smoothing on stratigraphic plots of angle from dipole axis. Magnetozones are correlated with the standard polarity-chronologic intervals using K-A dates at nine stratigraphic levels. The main change from our previous interpretation is that the reversed zone in the Basal Member of the Shungura Formation is correlated with the top of the Gilbert Epoch rather than with the Mammoth event of the Gauss Epoch. Thus the Basal Member and Member A are somewhat older than we previously believed, but age assignments for major fossil localities are unaffected. The inferred age ranges for the Shungura and Usno Formations are 3.5 to 0.8 Myr and 3.7 to 2.8 Myr respectively. The present analysis yields five zones of normal polarity in the lower Matuyama Reversed Epoch, that is, between the Matuyama/Gauss transition and the base of the Olduvai. All were found both in the previous data and in the new samples taken at different locations. For three of the five zones an unbroken series of normal samples extends over several lithologies, so a geomagnetic event is indicated.

Paleomagnetic measurements are reported for 500 sites in the lower Omo basin of southwestern Ethiopia, an important region for mammalian and hominid fossils. Magnetozones are defined with varying degrees of reliability for more than 700 m of measured stratigraphic section. In a half dozen sedimentary cycles of lower Member G at the locality sampled, we found the concreted basal sand to be normally magnetized and the upper silt to be reversely magnetized. We hypothesize a reversed primary magnetization of all these beds and a hard secondary magnetization of the permeable beds by groundwater. A chronological interpretation is proposed consistent with K/Ar dates on interbedded tuffs, faunal correlation with Bed I at Olduvai Gorge, and the detailed stratigraphy of J. De Heinzelin and P. Haesaerts. The exposed section is found to span the age range 3.2-0.9 m.y. For the lower Matuyama epoch the following suggestions are made about the fine structure of the geomagnetic polarity scale: (1) there are at least two and possibly three Reunion events near 2.0 m.y., (2) the “X” anomaly of J.R. Heirtzler et al. (1968) does represent a normal event near 2.3 m.y., (3) the Gilsa and Olduvai events are the same.

An approach to module generation that does not require the construction of parametrized software procedures is presented. It is a design-by-example method that is based on the following concept: an example module (e.g., a 16-b multiplier) realizes a function between the set of input combinations and the set of output combinations. In many applications, only a subset of input combinations (e.g., 8-b instead of 16-b inputs) is used. The restriction of the module's function to this subset can be realized by a simpler module. REDUSA constructs this module automatically by a reduction of the example module. This approach offers important advantages in both the construction and verification aspected of module generators. >

Limburgs Univ Ctr, Inst Mat Res, B-3590 Diepenbeek, Belgium. XPEQT, B-3980 Tessenderlo, Belgium. IMEC, B-3001 Heverlee, Belgium. Chartered Semicond Mfg Ltd, Singapore 738406, Singapore.Andries, E, Limburgs Univ Ctr, Inst Mat Res, Wetenschapspk 1, B-3590 Diepenbeek, Belgium.

Reliability analysis on Electro-Absorption Modulators reveals two degradation parts, trap generation and filling of pre-existing defects on Ge/Si and Ge/Ox interface. After stress, electro-optical extracted parameters indicate no impact of temperature, bias or stress time.