Ultra low-k dielectric films are expected to widely replace SiO2 as the interlayer dielectric for the next-generation microelectronic devices. A challenge facing the integration of these dielectrics in manufacturing is their interactions with gaseous contaminants, such as moisture and isopropanol, and the resulting change in their properties. Moisture retained in the film not only has detrimental effect on the k value of the film but also causes reliability and adhesion problems due to gradual outgassing. The physical and chemical interactions of moisture with porous spin-on and chemical vapor deposited (CVD) dielectrics are investigated using temperature- and concentration-programmed exposure and purge sequence together with trace moisture analysis, using atmospheric pressure ionization mass spectrometry.The model compounds in this study are porous Methylsilsesquioxane and Black Diamond II films, deposited and treated under typical manufacturing conditions. Transmission Electron Microscope (TEM) studies showed that etching and ashing processes resulted in the formation of two layers, a damaged layer and non-damaged layer, which significantly changed moisture interaction properties.Moisture sorption and desorption studies showed that as compared to SiO2 these films not only have a higher uptake capacity but also a slower and more activated moisture removal process. This could be a significant problem in successful integration of these films in IC manufacturing process.A process model was developed that provided information on the mechanism and kinetics of moisture uptake and release in thin porous films. The model elucidated the effect of film properties on the contamination uptake as well as outgassing. The model is a valuable tool for designing an optimum process for contamination control and removal in porous films.Another concern in IC manufacturing is the outgassing of impurities of electropolished stainless steel (EPSS) surfaces used in UHP gas distribution system. Moisture interaction with EPSS surface is studied in sub ppb range. A fundamental model was developed to study the mechanism and kinetics of moisture uptake and release from EPSS. The model developed would be a valuable tool for designing an optimum process for contamination control and to predict the moisture dry down performance of large-scale, systems.

No description available.

The techniques of x-ray diffraction of liquids are employed to study the salt TlCo(CO)4 in two solvents, tetrahydrofuran and dimethylsulfoxide. Radial distribution functions calculated from scattering data are analyzed in terms of the structure of these solutions, and the results are compared to those of other studies of the same and similar solutions investigated by infrared techniques. In tetrahydrofuran, a solvent of low dielectric constant, the evidence indicates close association of anion and cation, and contact ion pair and covalent models are presented and discussed. In dimethylsulfoxide, a solvent of high dielectric constant, the evidence indicates relatively loose association or no association of anion and cation, and solvent-separated ion pair and free ion models are presented and discussed.

A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy. Johannesburg, May 23, 2014. / A systematic experimental investigation was performed of the phenomenon of fine structure, with emphasis on the region of the Isoscalar Giant Quadrupole Resonance (ISGQR), in nuclei across stable even-even neodymium isotopes. The 200 MeV proton beams were delivered by the Separated Sector Cyclotron (SSC) facility of iThemba Laboratory for Accelerator Based Sciences (iThemba LABS). Measurements were made using the state-of-the-art K = 600 magnetic spectrometer, where unique high energy-resolution ( E ≈ 42 − 48 keV FWHM) proton inelastic scattering results were obtained on 142Nd, 144Nd, 146Nd, 148Nd and 150Nd targets. All measurements were taken at θLab = 8◦, where the cross-section of the ISGQR is at a maximum. An additional measurement was also made for the 142Nd at θLab = 7◦. Nuclei with mass number A ≈ 150 and neutron number N ≈ 90 are of special interest since they occupy that region of the nuclide chart wherein the onset of permanent prolate deformation occurs. The stable neodymium (Z = 60) isotopes have been chosen in the present study in order to investigate the effects accompanying the onset of deformation on the excitation energy spectra in the ISGQR region (9 ≤ Ex ≤ 15 MeV). The neodymium isotopes extend from the semi-magic N = 82 nucleus (142Nd) to the permanently deformed N = 90 (150Nd) nucleus. In order to emphasize the ISGQR in the measured excitation energy spectra, a Discrete Wavelet Transform (DWT) background subtraction was carried out. This model independent method for background determination decomposes the spectrum into various approximations and details through the application of high pass and low pass filters. A comparison of the resonance widths extracted shows a systematic broadening of the ISGQR (􀀀 = 3.220 MeV to 5.100 MeV), moving from spherical 142Nd to highly deformed 150Nd nuclei as has already been observed for the Isovector Giant Dipole Resonance (IVGDR) excited by γ-capture. Even though it is known that the IVGDR spectacularly splits and shows a double bump for the deformed 150Nd, no obvious splitting of the ISGQR was observed. In order to investigate the fine structure of the ISGQR, a theoretical microscopic calculation termed the Quasiparticle-Phonon Model (QPM) was applied to predict excitation energy spectra for 142−146Nd targets. These calculations were based on the one- plus two-phonon configuration. Characteristic energy scales were extracted for the resonance region using the Continuous Wavelet Transform (CWT) technique, on both experimental data and theoretical predictions. Comparison of the resulting characteristic energy scales suggests the coupling to low-lying collective vibrations as the dominant contributor to the ISGQR decay width. Level densities of 2+ states were extracted through the application of a fluctuation analysis technique, for full spectra from the ground state upwards in all five Nd targets. Comparisons are made with theoretical predictions from the Back Shifted Fermi Gas, Hartree-Fock-BCS and Hartree-Fock-Bogoluibov models. While there is generally an excellent agreement between experimental level densities and theoretical predictions from the ground state up to less than 10 MeV excitation, there is a marked disagreement beyond 10 MeV in all target nuclei. Comparison of the experimental results for the Nd isotope chain shows a clear systematic trend in which the onset of this disagreement occurs at lower and lower excitation energies, moving from low to high mass. For the spherical 142Nd nucleus the deviation occurs at about 9 MeV while in the case of the deformed 150Nd this occurs much earlier at about 4 MeV, all limited to a maximum of 103 MeV−1 by the energy resolution of the present experiment. Additionally, measurements of elastic scattering and inelastic excitation of lowlying collective states in 144−150Nd has also been possible. Excitation energy spectra in all targets predominantly exhibited various 2+ states, owing to the “spin-filter” effects. A single strong 3− 1 state, together with a weak 4+ 1 state were observed in each target nucleus. Angular distributions were obtained for the various ground and excited states by applying the optical model of elastic scattering and Distorted Wave Born Approximation (DWBA) of inelastic scattering. Deformation lengths δL were obtained for most of the states and these were in good agreement with previously obtained results from the literature.

The main goal in biopharmaceutical production is achieving high volumetric productivity while maintaining product quality (i.e. glycosylation). The objectives of this project were to explore the use of dielectric analysis in the early detection of cell demise and to analyze the impact of nucleotide / nucleotide sugar precursor feedings in biopharmaceutical production and glycosylation. Measurements of changes in the polarizability of individual cells can be performed in a dielectrophoretic (DEP) cytometer designed at the University of Manitoba. In this instrument the trajectory of individual cells was tracked according to their polarizability and recorded as a force index (FI). The identified sub-populations from a batch bioreactor and apoptosis-induced cultures were correlated with the fluorescent markers of apoptosis analyzed in a flow cytometer. Discrete cell sub-populations were identified as cells passed through the various stages of apoptosis. In the batch and the starvation culture the early changes in the measured FI of cells correlated with the Annexin V fluorescent assay associated with early phase apoptosis. For the oligomycin and staurosporine cultures changes in the FI could be correlated to modifications in the mitochondrial metabolism linked with early apoptosis for both inducers. In fed-batch experiments 10 mM galactose alone or 20 mM galactose in combination with 1 mM uridine or 1 mM uridine + 8 μM MnCl2 was added to the basal and feed medium for two CHO cell lines to determine their impact on the biopharmaceutical production and the glycosylation process. The results showed that the addition of all three precursors combined increased UDP-Gal, which increased and maintained the galactosylation index during the bioprocess for CHO-EG2 and CHO-DP12 cultures by 25.4% and 37.9%, respectively, compared to the non-supplemented fed-batch culture. In both cell lines saturation was reached when a further increase in the UDP-Gal concentration did not increase the galactosylation. A negative impact on cell growth was observed with the uridine addition in the CHO-EG2 culture, which was linked to the CHO-EG2 cell line being DHFR-/-. This work presents a dielectric detection method to monitor early changes in the cell metabolism and information for shifting and maintaining galactosylation during biopharmaceutical production. / February 2016

Lee Wai Ming. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 177-181). / List of Figures and Tables --- p.iii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Photonic Band Gap materials --- p.1 / Chapter 1.2 --- Theoretical Calculation on PBG materials --- p.5 / Chapter 2 --- Plane Wave Expansion --- p.13 / Chapter 2.1 --- Plane Wave Expansion within Scalar Wave Approximation --- p.14 / Chapter 2.2 --- Plane Wave Expansion to Scalar I and II Equations --- p.21 / Chapter 3 --- Formalism of Photonic k.p Theory --- p.33 / Chapter 3.1 --- Vectorial k.p formulation --- p.33 / Chapter 3.2 --- Scalar k. p formulations --- p.36 / Chapter 4 --- Implementation and k.p Band Structures --- p.38 / Chapter 4.1 --- Evaluation of Integrals plj and qlj --- p.38 / Chapter 4.2 --- k.p Band Models --- p.47 / Chapter 5 --- Dependence of k .p Parameters on Dielectric Contrast and Fill- ing Ratio --- p.57 / Chapter 5.1 --- Accuracy of Integrals plj and qlj --- p.57 / Chapter 5.2 --- Sensitivity of k.p Parameters to System Parameters --- p.71 / Chapter 6 --- Empirical Tight-binding Scheme --- p.99 / Chapter 6.1 --- Electronic Tight Binding Approximation --- p.99 / Chapter 6.2 --- Empirical Tight-binding Scheme --- p.101 / Chapter 7 --- Summary --- p.137 / Chapter A --- Preprint of Ref. [36] --- p.144 / Chapter B --- The Coefficients in Eq. (2.22) --- p.161 / Chapter C --- Formalism of Photonic k.p Theory --- p.163 / Chapter D --- The Coefficients in Eq. (5.2) --- p.166 / Chapter E --- The Coefficients in Eq. (5.3) --- p.168 / Chapter F --- The Coefficients in Eq. (6.15) --- p.170

Ng Sheung Wah = 米氏散射--以形態關聯共振分析之 / 伍尚華. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves [112]-114). / Text in English; abstracts in English and Chinese. / Ng Sheung Wah = Mi shi san she--yi xing tai guan lian gong zhen fen xi zhi / Wu Shanghua. / Abstract --- p.i / Acknowledgements --- p.iii / Contents --- p.iv / List of Figures --- p.vii / List of Tables --- p.xii / Chapter Chapter 1. --- Introduction --- p.1 / Chapter Chapter 2. --- MDR Expansion of Scattering Matrix --- p.7 / Chapter 2.1 --- Introduction --- p.7 / Chapter 2.2 --- Definition of Scattering Matrix --- p.8 / Chapter 2.3 --- Expansion of St with MDR's --- p.9 / Chapter 2.4 --- The Scattering Matrix in Mie's Theory for Uniform Dielectric Spheres --- p.12 / Chapter 2.5 --- Convergence of the Series --- p.15 / Chapter 2.6 --- Contributions of Different MDR's in Cross Section --- p.19 / Chapter Chapter 3. --- Numerical Method for MDR's --- p.27 / Chapter 3.1 --- Multipole Expansion --- p.27 / Chapter 3.2 --- Green's Theorem --- p.29 / Chapter 3.3 --- Translational Matrix --- p.31 / Chapter 3.4 --- Rotational Matrix --- p.36 / Chapter 3.5 --- Transfer Matrix to the Outside --- p.39 / Chapter 3.6 --- Diagonalization --- p.40 / Chapter Chapter 4. --- Degenerate Perturbation for MDR --- p.44 / Chapter 4.1 --- Introduction --- p.44 / Chapter 4.2 --- Perturbation Theory for Degenerate Systems --- p.44 / Chapter Chapter 5. --- Microdroplets with multiple inclusions: Experiments --- p.52 / Chapter 5.1 --- Introduction --- p.52 / Chapter 5.2 --- Method --- p.52 / Chapter Chapter 6. --- Formalism for Scattering from Inhomogeneous Spheres --- p.61 / Chapter 6.1 --- The Green's Function Formalism --- p.61 / Chapter 6.2 --- MDR Expansion of Dyadic Green's Function --- p.62 / Chapter 6.3 --- Cross Section Calculation --- p.64 / Chapter Chapter 7. --- Simulation of the Multiple Scattering Experiment --- p.66 / Chapter 7.1 --- Introduction --- p.66 / Chapter 7.2 --- Method --- p.67 / Chapter Chapter 8. --- Numerical Results of Multiple Scattering --- p.69 / Chapter 8.1 --- Introduction --- p.69 / Chapter 8.2 --- Comparisons of the Experimental and Simulation Result --- p.69 / Chapter 8.2.1 --- General Trend --- p.69 / Chapter 8.2.2 --- Position of the Resonance --- p.70 / Chapter 8.2.3 --- Width of the Resonance --- p.71 / Chapter Chapter 9. --- Scaling Behaviours of the Perturbation in MDR's --- p.83 / Chapter 9.1 --- Introduction --- p.83 / Chapter 9.2 --- Scaling Behaviours of MDR's shifts --- p.84 / Chapter 9.3 --- Analytical Approach to the Scaling Behaviours --- p.84 / Chapter 9.3.1 --- Average Shifts --- p.85 / Chapter 9.3.2 --- """slope"" of the Shifts" --- p.87 / Chapter 9.3.3 --- Spreading of the shifts --- p.87 / Chapter Chapter 10. --- Conclusion --- p.96 / Appendix A. Transverse Dyadic Green's Function Expansion --- p.98 / Appendix B. Calculation of the Self-Energy Matrix to First Order --- p.101 / Appendix C. Computer Code for Diagonalization of Δmm --- p.103 / Bibliography --- p.112

This work introduces formulae of Fresnel type related to reflection and transmission of a plane electromagnetic wave from a moving boundary separating two isotropic dielectrics. The dielectrics themselves remain immovable, so, the ensuing material formation represents an example of an activated dynamic material assembled from the LC-arrays serving as the discrete versions of each dielectric.

Lead-based and lead-free ferroelectric ceramic materials were prepared at low sintering temperatures with particular regard to their applications in thick film piezoelectric components. This project is focused on the development of processing methods and novel compositions to be used for thick film production by electrophoretic deposition (EPD) on heat-resistant alloys. Lead-based glasses and an oxide mixture (LiCO3, Bi2O3 and CuO), denoted LBCu, with low melting points were used as sintering aids for lanthanum-doped lead zirconate titanate (PLZT) ceramics. The required temperature to achieve dense ceramics was reduced from 1250 to 950 °C. It was found that the highest ferroelectric properties were obtained by the use of LBCu in comparison with those incorporating glass additives due to the shielding effect of the glass phase between the ferroelectric grains. However, the results of thick film preparation shown that the samples with glass additives were much smoother and relatively free of cracks up to 1000 ÂoC. In terms of lead-free ceramics, novel compositions were prepared, based on (Ba,Ca)(Zr,Ti)O3-(K0.5Bi0.5)TiO3 (BCZT-KBT) solid solutions having various Ca and Zr contents. The new solid solutions exhibited interesting features comprising core-shell type microstructures and relaxor ferroelectric behaviour in addition to reduced sintering temperatures and higher Curie point compared with BCZT ceramics. The required sintering temperature reduced to 1125 °C at 65% KBT, in comparison with 1500 °C for pure BCZT. The results showed that the compositional heterogeneity in the shell regions was reduced by air quenching, relative to that of the slow-cooled state, due to the retention of the more chemically-homogeneous high temperature state by the quenching process. The improvements were evident in increased polarisation, piezoelectric coefficient and depolarisation temperature values. However, the slow-cooled samples exhibited high reversible strain levels due to the presence of polar nanoregions (PNRs) in the ergodic state within the shell regions. Comparing the results obtained for two BCZT compositions, it was demonstrated that the stability of the ferroelectric tetragonal phase in slow-cooled BCZT-KBT samples was improved for the ceramic with lower Ca and Zr concentrations, denoted x=0.06, in comparison with that for higher levels, denoted x=0.15. Moreover, the electric field-induced ferroelectric state in the quenched ceramic with x=0.06 was found to be more stable during heating, giving rise to an enhanced depolarisation temperature.

Yam Chi Tong = 懸浮顆粒之介電反應 / 任智堂. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 76-79). / Text in English; abstracts in English and Chinese. / Yam Chi Tong = xuan fu ke li zhi jie dian fan ying / Ren Zhitang. / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Spectral Representation of a Pair of Polydisperse Cylinders --- p.3 / Chapter 2.1 --- Introduction --- p.3 / Chapter 2.2 --- Multiple Image Method --- p.4 / Chapter 2.2.1 --- Polydispersity in Size --- p.6 / Chapter 2.2.2 --- Polydispersity in Permittivity --- p.7 / Chapter 2.3 --- Spectral Representation --- p.9 / Chapter 2.3.1 --- Polydisperse Size Cylinders --- p.10 / Chapter 2.3.2 --- Polydisperse Permittivity Cylinders --- p.12 / Chapter 2.4 --- Numerical Results --- p.13 / Chapter 2.4.1 --- Polydispersity in Size --- p.14 / Chapter 2.4.2 --- Polydispersity in Permittivity --- p.17 / Chapter 2.5 --- Conclusion --- p.22 / Chapter 3 --- Dielectric Behaviors of Polydisperse Colloidal Suspensions --- p.24 / Chapter 3.1 --- Introduction --- p.24 / Chapter 3.2 --- Dielectric Dispersion Spectral Representation --- p.26 / Chapter 3.3 --- Polydisperse Colloidal Suspensions --- p.28 / Chapter 3.4 --- Numerical Results --- p.30 / Chapter 3.4.1 --- Monodisperse Limit --- p.31 / Chapter 3.4.2 --- Influence of the Medium Conductivities --- p.32 / Chapter 3.4.3 --- Effect of Conductivity Contrasts --- p.34 / Chapter 3.4.4 --- Effect of Varying the Volume Fractions --- p.37 / Chapter 3.5 --- Conclusion --- p.41 / Chapter 4 --- Dielectric Behaviors of Shelled Cell Suspensions --- p.43 / Chapter 4.1 --- Introduction --- p.43 / Chapter 4.2 --- Shelled Spherical Particle Model --- p.46 / Chapter 4.2.1 --- Intrinsic Dispersions --- p.47 / Chapter 4.3 --- Numerical Results --- p.49 / Chapter 4.3.1 --- One Type of Shelled Cells --- p.51 / Chapter 4.3.2 --- Mixture of Two Types of Shelled Cells --- p.60 / Chapter 4.4 --- Conclusion --- p.62 / Chapter 5 --- Dielectric Behaviors of Compositionally Graded Films --- p.64 / Chapter 5.1 --- Introduction --- p.64 / Chapter 5.2 --- Discrete Layer Model --- p.65 / Chapter 5.2.1 --- Linear Profiles --- p.67 / Chapter 5.2.2 --- Gaussian Profiles --- p.67 / Chapter 5.3 --- Continuously Graded Model --- p.68 / Chapter 5.3.1 --- Linear Profiles --- p.68 / Chapter 5.3.2 --- Gaussian Profiles --- p.69 / Chapter 5.4 --- Conclusion --- p.72 / Chapter 6 --- Summary --- p.74 / Bibliography --- p.76 / Chapter A --- The Maxwell-Garnett Approximation --- p.80 / Chapter B --- The Bergman-Milton Spectral Representation --- p.82