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Deposition and characterization of titanium dioxide and hafnium dioxide thin films for high dielectric applications /Yoon, Meeyoung. January 2001 (has links)
Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 152-158).
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Surface and interfacial chemistry of high-k dielectric and interconnect materials on siliconKirsch, Paul Daniel. January 2001 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references. Available also from UMI/Dissertation Abstracts International.
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Anisotropy of low dielectric constant materials and reliability of Cu/low-k interconnects /Cho, Taiheui, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 160-167). Available also in a digital version from Dissertation Abstracts.
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Process development, material analysis, and electrical characterization of ultra thin hafnium silicate films for alternative gate dielectric applicationGopalan, Sundararaman. January 2002 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.
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Phase-field modeling of piezoelectrics and instabilities in dielectric elastomer compositesLi, Wenyuan, 1982- 01 February 2012 (has links)
Ferroelectric ceramics are broadly used in applications including actuators, sensors and information storage. An understanding of the microstructual evolution and domain dynamics is vital for predicting the performance and reliability of such devices.
The underlying mechanism responsible for ferroelectric constitutive response is
ferroelectric domain wall motion, domain switching and the interactions of domain
walls with other material defects.
In this work, a combined theoretical and numerical modeling framework is
developed to investigate the nucleation and growth of domains in a single crystal of
ferroelectric material. The phase-field approach, applying the material electrical
polarization as the order parameter, is used as the theoretical modeling framework to
allow for a detailed accounting of the electromechanical processes. The finite element
method is used for the numerical solution technique. In order to obtain a better
understanding of the energetics of fracture within the phase-field setting, the J-integral is
modified to include the energies associated with the order parameter. Also, the J-
integral is applied to determine the crack-tip energy release rate for common sets of
electromechanical crack-face boundary conditions. The calculations confirm that only
true equilibrium states exhibit path-independence of J, and that domain structures near
crack tips may be responsible for allowing positive energy release rate during purely
electrical loading.
The small deformation assumption is prevalent in the phase-field modeling
approach, and is used in the previously described calculations. The analysis of large
deformations will introduce the concept of Maxwell stresses, which are assumed to be
higher order effects that can be neglected in the small deformation theory. However, in
order to investigate the material response of soft dielectric elastomers undergoing large
mechanical deformation and electric field, which are employed in electrically driven
actuator devices, manipulators and energy harvesters, a finite deformation theory is
incorporated in the phase-field model. To describe the material free energy,
compressible Neo-Hookean and Gent models are used. The Jaumann rate of the
polarization is used as the objective polarization rate to make the description of the dissipation frame indifferent. To illustrate the theory, electromechanical instabilities in composite materials with different inclusions will be studied using the finite element
methods. / text
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The effects of post-ash cleaning and chemical treatments on the dielectric properties and reliability of Cu/low-k interconnect structuresBorthakur, Swarnal 28 August 2008 (has links)
Not available / text
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Tribological, Thermal and Kinetic Characterization of Dielectric and Metal Chemical Mechanical Planarization ProcessesSorooshian, Jamshid January 2005 (has links)
This dissertation presents a series of studies that describe the impacts of, among other things, temperature and kinematics on inter-level dielectric (ILD) and metal chemical mechanical planarization (CMP) processes. The performance of CMP is often evaluated in terms of removal rate, uniformity, planarization length, step height, defects and resulting topography such as erosion and dishing. The assessment of these parameters is significantly dependent on the selection of tool and consumable set (polishing pad or slurry type), as well as the kinematics involved in the process. Variations in pressure, sliding velocity, temperature and slurry flow rate are just a few of the dynamic inputs that can affect polishing performance. The studies presented in this dissertation focus on some of these external parameters and how they influence the mechanisms involved with the CMP process and their overall outcome on performance.Studies presented in this dissertation include topics such as the effects wafer-ring configurations and wafer geometries on the applied wafer pressure distribution across a wafer surface. In addition to this, another study related to understanding applied wafer pressure investigated the estimation of the effective (envelop) pressure for patterned shallow trench isolation (STI) wafers during CMP. When considering the regularity of issues such as changing wafer geometries and wafer feature patterns, these two studies provided significant insight on the potential issues that could arise during CMP when dealing with such events, as well as potential solutions for controlling such events.Another study in this dissertation investigated the effects of polishing pad type on dielectric CMP performance. Polishing pads varied in thickness and grooving, and tests were done to characterize the tribological and thermal behavior of the pads under a wide range of p × V and slurry flow rate conditions. Of key importance in this study was observing any combined effects between changes in platen set point temperature and pad type on ILD removal rate.The greatest contribution to this dissertation involved studies related to the role of temperature in CMP. These studies implemented variable platen set point temperatures to further understand the thermal effects on parameters such as removal rate and coefficient of friction (COF). As a result of these studies, a new removal rate model based on flash heating was developed to describe observed non-linear trends in removal rate. The application of this model has shown great utility in removal rate prediction when compared to prior models.
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Dielectric heating for antimicrobial treatment of fresh meatsLacroix, Karine. January 2001 (has links)
The present study focussed its energy on the evaluation of a dielectric pasteurization for fresh meat. This research investigates ways to reduce the bacterial load on raw beef surfaces with microwave or RF energy in combination with different packaging methods and a natural antimicrobial combination. / Sterilized raw beef cores were inoculated with Escherichia coli biotype 1, Pseudomonas D17 and Carnobacterium "845" of a known inoculum. Treatments were imposed to the cores and packaged in either retail or vacuum packaging. The treatments for the full experiment were RF1 (600W-30s, 400W-30s, 200W-60s), RF2 (600W-30s, 400W-30s, 100W-60s), Nisin-lysozyme alone, Nisin-lysozyme/RF1 and Nisin-lysozyme/RF2. Positive and negative control treatments were added to facilitate the comparison. Microbial analysis, pH measurement, L*a*b* colour measurement and sensory evaluation were performed during the storage period to follow the evolution of the meat samples. / No significant reductions (P < 0.05) in bacterial numbers were observed in this study and none of the treatments showed positive results. Therefore the treatments used would not be considered as a good pasteurization treatment for keeping the quality of raw beef. (Abstract shortened by UMI.)
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A second order isoparametric finite element analysis of dielectric waveguides with curved boundaries /Welt, Daniel. January 1984 (has links)
No description available.
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Nanosecond pulse electroporation of biological cells: The effect of membrane dielectric relaxationSalimi, Elham 07 April 2011 (has links)
Nanosecond pulse electroporation of biological cells is gaining significant interest due to its ability to influence intracellular structures. In nanosecond pulse electroporation of biological cells nanosecond duration pulses with high frequency spectral content are applied to the cell. In this research we show that accurate modeling of the nanosecond pulse electroporation process requires considering the effect of the membrane dielectric relaxation on the electric potential across the membrane. We describe the dielectric relaxation of the membrane as dispersion in the time-domain and incorporate it into the nonlinear asymptotic model of electroporation. Our nonlinear dispersive model of a biological cell is solved using finite element method in 3-D space enabling arbitrary cell structures and internal organelles to be modeled. The simulation results demonstrate two essential differences between dispersive and non-dispersive membrane models: the process of electroporation occurs faster when the membrane dispersion is considered, and the minimum required electric field to electroporate the cell is significantly reduced for the dispersive model.
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