bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Investigation of the Limit of Detection and the Scattering Dependence of the Optical Precipitate Profiler (OPP)
Authors: Mule'stagno L. , Hill D.E. , Standley R. , Olmo M. , Holzer J.C. , Falster R. , Fraundorf P. 
Published: April 2011

AbstractThe Optical Precipitate Profiler (OPP) and similar instruments are establishing themselves as routine techniques for measuring bulk micro-defect density (BMD) and denuded zone depths in semiconductor wafers. This task has traditionally been done by means of the cleave-and-etch technique in which defects are counted on a cleaved edge of an etched wafer using an optical microscope. The OPP makes this task faster, simpler and more accurate. In addition it can perform the measurement on a whole wafer.We have used the OPP to measure defect density and scattering intensities from a set of silicon wafers with different precipitate sizes. The wafers were all given the same nucleation heat treatment but the precipitates were then grown at 1000°C for 1, 2, 4, 8, 16 and 32 hours. The size distributions and densities of the precipitates in each wafer were determined by Transmission Electron Microscopy (TEM). In a second experiment wafers with precipitate densities varying over four orders of magnitude as determined by cleaveand-etch were also measured by the OPP.From these experiments we have estimated that the OPP can detect defects with an equivalent radius of 16 ± 8 nm and larger. We have also found that the scattering voltage (strength) depends on the precipitate radius, r3, as approximately r3 and that there is an upper number density limit above which the OPP is unable to measure the precipitate density accurately. For our setup this upper density limit was about 1.5 - 2.0 × 1010 defects/cm3 as measured by cleave-and-etch.
Compliant Substrates With an Embedded Twist Boundary
Authors: Lo Y. H. , Zhu Z. H. 
Published: April 2011

AbstractIn this article, we propose a new model to explain how heteroepitaxial layers grown on a twist-bonded thin layer may have a significantly reduced number of threading dislocations even if the strain in the epitaxial layers is relaxed. We first point out the deficiency in the existing compliant substrate theory by showing that all the synthesized “compliant substrates” fail to behave as “ideal” free-standing templates assumed by the current theory. Our new model is constructed on the base of stress field interactions between the heteroepitaxial layer and the embedded twist boundary. In the new model, the reduction in threading dislocation density originates from the extension of the dislocation half loops due to the effect of misfit dislocation pinning by the twist boundary. When the average size of the dislocation half loops increases substantially from micrometers to millimeters or even to the size of the wafer, the density of threading dislocations drops significantly. This model does not require any “macroscopic” motion between the bonded thin layer and the handle wafer as the current theory does, which makes it more agreeable with the experimental results
Experimental Characterization of Material Properties of 63Sn37Pb Flip Chip Solder Joints
Authors: Wiese S. , Feustel F. , Rzepka S. , Meusel E. 
Published: April 2011

ABSTRACTThe paper presents new material data of real flip chip solder joints. A testing apparatus was designed to perform reversible shear tests on flip chip joints. In contrast to previous test setups for similar purposes this tester provides an infinite stiffness, a very high precision force (1 mN resolution) and displacement (20 nm resolution) measurement. The experimental program included cyclic shear tests for elastic plastic material data as well as a newly developed reversal creep and relaxation test for time depended material properties. A subsequent FEM simulation was applied to evaluate experimental raw data and to determine the parameters of material models provided by ANSYSTM. A user defined creep model had been added to the source code, in order to receive a convenient solder model for FE-Analysis of SnPb37 flip chip solder joints under thermomechanical stresses in electronic packages. The results of this study shows that the material behavior of flip chip solder joints is much more like that of bulk samples with a comparable micro structure than it is commonly believed up to now, because of the previously published data.
Magnetic Order of Co0.1Pt0.9 in Proximity of CoPt3
Authors: Shapiro A.L. , Hellman F. , Fitzsimmons M.R. 
Published: April 2011

AbstractA polarized neutron reflectometry study of the magnetization density depth profile of a Co0.1Pt0.9-CoPt3 bilayer film found evidence for an induced moment in the Co0.1Pt0.9 overlayer in close proximity to the CoPt3 underlayer. If the moment of Co in these films is that of the bulk, then the μpt = 0.09(1)μB in the overlayer, and μpt = 0.04(1)μB, in the underlayer. In addition, ferromagnetic order of the Co0.1Pt0.9 overlayer was observed 8K above Tc for the material in the bulk.
Patterned Garnet Films on Substrates with Ion-Beam Bombarded Micropatterns
Authors: Okamura Yasuyuki , Yamamoto Sadahiko 
Published: April 2011

AbstractWe report the selected-area epitaxy of rare-earth iron garnet crystalline and amorphous straight ridge patterns, from 4μm to 8μm in width, deposited on Gd3Ga5O12 single crystal substrates. These samples were fabricated via a sputter epitaxial method on substrates that were partially etched by ion-beam bombardment. The strip pattern direction has given the considerable influence on the crystal-graphic formation of the sidewall of the grown ridge. The ridge shapes were similar to results that have been reported for the dissolution forms of garnet crystals in phosphoric acid and the facet of garnet crystals grown from flux. Furthermore, we have successfully grown both an epitaxial garnet film onto an amorphous film and an amorphous straight ridge with a triangular shape surrounded by crystal.
Integrated Nonreciprocal Devices for Application in Optical Communication Systems
Authors: Shintaku T. , Sugimoto N. , Tate A. , Kubota E. , Kozawaguchi H. , Katoh Y. 
Published: April 2011

AbstractWe describe our recently developed integrated isolators. Their structure is simple, in that it consists solely of a single-mode channel magneto-optic waveguide. The operating principle is that a backward fundamental TM mode wave is converted to higher-order or radiation TE modes while a forward fundamental TM mode wave propagates with no mode conversion. These isolators are realized using a single-mode rib channel waveguide in Ce-substituted yttrium iron garnet which has a very large Faraday rotation. We obtain 13-27 dB isolation around a wavelength of 1.55 μm. We also review our recent study on a hybrid-integrated polarization-independent optical circulator based on a nonreciprocal Mach-Zehnder interferometer which does not need a polarization-beam splitter. We obtain 14.1-23.7 dB isolation at λ = 1.55 μm.
Recent Advances in Magnetostatic Waves-Based Integrated Magnetooptic Bragg Cell Modulators in Yig-Ggg Waveguides
Authors: Tsai Chen S. 
Published: April 2011

AbstractThe most recent advances in the integration architecture and diffraction efficiency of magnetostatic wave (MSW)-based guided-wave magnetooptic (MO) Bragg cell modulators in yttrium iron garnet-gadolinium gallium garnet (YIG-GGG) waveguides are reported. A curved ion-milled hybrid waveguide lens pair has been integrated with a MO Bragg cell modulator in a taper waveguide with dimensions of 6.0x16.0mm2 to facilitate the collimation and focusing functions. An enhancement in the Bragg diffraction efficiency by two-to six-fold has been accomplished using a non-uniform bias magnetic field. An oscillator-based MO Bragg cell modulator has also been constructed and has provided a Bragg diffraction efficiency which is higher by a factor of two to four than that of a conventional delayline-based modulator.
Colloidal Particles: Spherical Yttrium Iron Garnet
Authors: Godoi R.H.M. , Jafelicci M. , Marques R.F.C. , Varanda L.C. 
Published: April 2011

AbstractThe purpose of this work is to obtain spherical particles YIG from micrometric to nanometric scales. The spherical particles were obtained from cation hydrolysis in acid medium by adding urea or ammonia in order to carry out a homogeneous nucleation process up to 90°C. Different composition and morphology were achieved by changing reactant concentrations, precipitation agent and stabilizing agent. X-ray diffractometry, electrophoretic mobility, transmission and scanning electron microscopies were carried out on these particles to investigate the phase identification, mobility, morphology and particle size. Crystalline YIG, with spherical characteristics, was obtained. The surface potential presented different characteristics for different dispersion media.
Nonlinear Magneto-Optical Kerr Effect in Gd-Containing Langmuir-Blodgett Films
Authors: Didenko N.V. , Fedyanisn A.A. , Khomutov G.B. , Murzina T.V. , Aktsipetrov O.A. 
Published: April 2011

AbstractMagnetization induced second harmonic generation (MSHG) is observed in Gd-containing Langmuir-Blodgett (LB) films. The nonlinear optical studies reveal significant alterations in the second harmonic generation (SHG) intensity and in the polarization and phase of the second harmonic (SH) wave induced by application of DC magnetic field. The violation of polarization selection rules and the diffusenes of the MSHG intensity indicates the inhomogeneity of LB structure and the hyper-Rayleigh scattering mechanism of MSHG. The latter proofs the existence of 2D-islands of Gd ions in the structural unit of the LB films which is composed by monolayer of rare-earth ions compressed between two layers of stearic acid molecules.
Synthesis of nanostructured silica powders by a room temperature aerosol process
Authors: Hyeon-Lee Jingyu , Beaucage Gregory , Pratsinis Sotiris. E. 
Published: April 2011

ABSTRACTNano-sized porous silica powders are synthesized by a room temperature aerosol process. Reactant mixing configuration, reactant temperature, and drying temperature effects on the physical and morphological features of these powders are studied by nitrogen adsorption and small angle xray scattering techniques. These silica powders have high specific surface areas up to 600 m2/g, and show narrowly confined mesoporous characteristics. The powders display some structural change with temperature. The morphological features are modeled as mass fractals by small angle x-ray scattering. Measured fractal dimensions are around 2.8, indicating diffusion limited growth processes.
Schnell Gel: Rapid Formation of Low Density Gels from a Tetra(Fluoroalkoxy)Silane
Authors: Sharp Kenneth G. 
Published: April 2011

ABSTRACTA new family of simple precursors to silica gel has been developed. The gel precursors are tetra(polyfluoroalkoxy)silanes, the prototype being Si(OCH2CF3)4. Formation of transparent monolithic gels with no added catalyst can be six orders of magnitude faster than comparable reactions of Si(OCH2CH3)4[TEOS]. Extremely low density gels can be generated in minutes at concentrations at which TEOS does not gel at all. Pore sizes in the wet gels were estimated from hydrodynamic relaxation in a beam-bending experiment on cylindrical logs. In a gel at 1% solids, the pore size was approximately 100 nm. Monolithic gels can be created at concentrations at least as low as 0.1% solids and have higher moduli than predicted. NMR and GC/IR evidence indicates extremely facile hydrolysis and condensation pathways and very few silanol or cyclic intermediates in the sol. The chemistry can also be conducted in perfluorinated solvents, enabling synthesis of silica/fluoropolymer nanocomposites.
Drying of Nano-Size Materials
Authors: Maskara A. , Menon V. , Wallace S. , Smith D.M. 
Published: April 2011

ABSTRACTThe physics and chemistry of drying of nano-size materials (porous solids or particles with characteristic dimensions less than 100 nm) is considered. Approaches for reducing capillary pressure and surface passivation in an effort to avoid shrinkage are presented. In addition, the effect of key variables on drying costs (both capital and operating/energy) is presented.
Ultrasonic Treatment of Nanostructured Powders for the Production of Zirconia Ceramics
Authors: Khasanov O.L. , Pokholkov Yu.P. , Sokolov V.M. , Dvilis E.S. , Strutz V.K. , Ivanov Yu.F. , Dedov N.V. 
Published: April 2011

ABSTRACTThe structure and mechanical properties of Y-TZP nanoceramics produced by ultrasonic (US) action on nanostructured ZrO2 – 5.4wt% Y2O3 powder have been analyzed. The influence of powder US-treatment on elastic aftereffect of a compact, uniformity of ceramics volumetric shrinkage, on ceramic nanostructure forming and as a result on its density, hardness, impact strength was shown. The optimum of power level of US-action was defined.
Microstructures and Photoluminescence in Nanocrystalline Barium Titanate
Authors: Zhang M. S. , Yu J. , Zhang W. F. , Yin Z. , Chen W. C. 
Published: April 2011

ABSTRACTBarium titanate ultrafine particles are prepared by hydrothermal method at low temperature. Their phase structures and photoluminescence (PL) properties are examined by X-ray diffraction and Raman spectroscopy. The critical size of the cubic-tetragonal phase transition is about 48 nm and the lattice parameter ratio c/a equals 1.003. Strong photoluminescence is observed with central frequency located at 695 nm. The spectral behaviors at different annealing times and temperatures are studied. We attribute them to the semiconducting hexagonal phase embeded in the nanophase cubic BaTiO3to form trap centers and cause PL process.
Crystal Growth Studies During Aerosol Synthesis of Nanostructured Fullerene Particles
Authors: Joutsensaari J. , Kauppinen E.I. , Bernaerts D. , Van Tendeloo G. 
Published: April 2011

ABSTRACTWe have studied crystal growth during aerosol synthesis of nanostructured C60, C70 and mixed fullerene particles. Fullerene particles have been produced by aerosol droplet drying and crystallization as well as via vapor condensation starting from solutions of fullerenes in toluene. Morphology, crystallinity and crystal structure of fullerene particles produced in various processing temperatures were studied by scanning and transmission electron microscopy. The results show that both highly disordered and single crystal particles with a size of about 100 nm are formed at reactor operating temperatures of 500 °C and above. The ultrafine particles formed via vapor condensation are mostly polycrystalline. Many of crystalline particles have perfectly faceted morphology, i.e., hexagonal plate-like, decahedral and icosahedral shapes. The plate-like particles are lamellar-twinned and the decahedral and icosahedral particles are multiply twinned. Crystallite formation and growth mechanisms of the particles are discussed. In addition, electron diffraction results show that fullerene alloys with fcc structure can be produced via aerosol synthesis methods.
The Effect of Oxide Layers on Gas-Generating Hydride Particles During Production of Aluminium Foams
Authors: Gergely V. , Clyne T. W. 
Published: April 2011

ABSTRACTMelt routes to metallic foam production offer attractions of low cost and the potential for good microstructural control. In situ gas generation may be preferable to external gas injection in terms of the important objective of generating a fine and uniform cell structure. The main difficulty with this approach has been that of ensuring that the gas-generating powder is suitably dispersed throughout the melt before the gas is released and the cells are formed.In the present paper, procedures are outlined for preparation of powders for use in aluminium melts, where gas will be released only after a suitable delay, allowing the powders to first become well-dispersed in the melt and solidification to start. Pre-treatment of the foaming agent also facilitates a flexible production of castings with various porosity at the same processing conditions simply by varying the thickness of a diffusion barrier layer on the gas-releasing agent. The role of the melt viscosity history, as a function of a heat extraction rate from the solidifying melt and an alloy composition, on the final porosity of the castings is also briefly discussed.
Lvophilic Liouid Porosimetry and a New Liouid Autoporosimeter
Authors: Tyomkin I. 
Published: April 2011

ABSTRACTLyophilic liquid porosimetry determines the volumes of different size pores by measuring the amount of liquid in these pores, thus, providing pore volume distribution (PVD) data for porous structures. Any liquid that wets the sample may be used. This opens unique opportunities for porous structure evaluation. It provides realistic PVD analysis when the liquid of interest changes the porous structure. It determines uptake/drainage hysteresis of real liquids. It allows direct measurements of uptake and retention capillary pressures with different amounts of liquid in a sample. Lyophilic liquid porosimetry determines liquid/solid contact angles of different size pores within the sample. It can also be used for PVD analysis of both soft, brittle materials and porous metal materials.
Process Modeling of Ti-6Al-4V SPM Materials
Authors: Ahmed S. S. , Huang G. , Gegel H. , Barker D. 
Published: April 2011

ABSTRACTStructural Porous Metals (SPM) was specifically designed to offer large weight reductions in structural applications. The pores of gas are incorporated into the SPM during hot isostatic pressing. Since the gas in the pores are at high pressure and are closed isolated pores, SPM can be processed by standard methods such as rolling or forging without collapsing the gas pores. The objective of this paper is to show that the combination of computer simulation and intrinsic workability modeling provide a rapid and cost-effective way, for understanding the process and selecting the process parameters. This paper explains how SPM material data and developed material density updating scheme can be used in conjunction with the existing theory and FEM model.
Compressive Deformation and Yielding Mechanisms in Cellular Al Alloys Determined Using X-ray Tomography and Surface Strain Mapping
Authors: Bart-Smith H. , Bastawros A.-F. , Mumm D. R. , Evans A. G. , Sypeck D. J. , Wadley H. N. G. 
Published: April 2011

ABSTRACTThe mechanisms of compressive deformation that occur in closed cell Al alloys have been established. This has been achieved by using x-ray computed tomography (CT) and surface strain mapping to determine the deformation modes and the cell morphologies that control the onset of yielding. The deformation is found to localize in narrow bands having width of order of a cell diameter. Outside the bands, the material remains elastic. The cells within the bands that experience large permanent strains are primarily elliptical. A group of cells work collectively to allow large localized deformation. Size does not appear to be the initiator of the deformation bands. Equiaxed cells remain elastic. The implications for manufacturing materials with superior mechanical properties are discussed. Visualization of internal deformation of a closed cell Al alloy core, as part of a sandwich panel construction, is also possible using x-ray tomography. Preliminary results for a punch indentation test are presented.
Model Based Temperature Control in RTP Yielding ±0.1 °C accuracy on A 1000 °C, 2 second, 100 °C/s Spike Anneal
Authors: Vandenabeele Peter , Renken Wayne 
Published: April 2011

ABSTRACTA Model Based Control method is presented for accurate control of RTP systems. The model uses 4 states: lamp filament temperature, wafer temperature, quartz temperature and TC temperature. A set of 4 first order, nonlinear differential equations describes the model. Feedback is achieved by updating the model, based on a comparison between actual (measured) system response and modeled system response.
Partial Transparency Effects of Silicon During Rapid Thermal Processing
Authors: Abramson A. R. , Tadal H. , Nieva P. , Zavracky P. , Miaoulis I. N. , Wong P. Y. 
Published: April 2011

ABSTRACTThe radiative properties of a silicon wafer undergoing Rapid Thermal Processing (RTP) are contingent upon the doping level of the silicon substrate and film structure on the wafer, and fluctuate drastically with temperature and wavelength. For a lightly doped substrate, partial transparency effects must be considered that significantly affect absorption characteristics. Band gap, free carrier, and lattice absorption are the dominant absorption mechanisms and either individually or in concert have considerable effect on the overall absorption coefficient of the silicon wafer. At high doping levels, partial transparency effects dissipate, and the substrate may be considered optically thick. A numerical model has been developed to examine partial transparency effects, and to compare lightly doped (partially transparent) and heavily doped (opaque) silicon wafers with a multilayer film structure during RTP.
Evaluation Of 2.0 nm Grown and Deposited Dielectrics in 0.1 μm PMOSFETs
Authors: Srivastava A. , Heinisch H. H. , Vogel E. , Parker C. , Osburn C. M. , Masnari N. A. , Wortman J. J. , Hauser J. R. 
Published: April 2011

ABSTRACTThe quality and composition of ultra-thin 2.0 nm gate dielectrics advocated for the 0.1 μm technology regime is expected to significantly impact gate tunneling currents, P+-gate dopant depletion effects and boron penetration into the substrate in PMOSFETs. This paper presents a comparative assessment of alternative grown and deposited gate dielectrics in sub-micron fabricated devices. High quality rapid-thermal CVD oxides and oxynitrides are examined as alternatives to conventional furnace grown gate oxides. An alternative gate process using in-situ boron doped and RTCVD deposited poly-Si is explored. PMOSFETs with Leff down to 0.06 μm were fabricated using a 0.1 μm technology. Electrical characterization of fabricated devices revealed excellent control of gate-boron depletion with the in-situ gate deposition process in all devices. Boron penetration of 2.0 nm gate oxides was effectively controlled by the use of a lower temperature RTA process. The direct tunneling leakage, although significant at these thicknesses, was less than 1 mA/cm2 at Vd = −1.2 V for all dielectrics. MOSFETs with comparable drive currents and excellent junction and off-state leakages were obtained with each dielectric.
The Effects of Small Concentrations of Oxygen in RTP Annealing of Low Energy Boron, BF2 and Arsenic Ion Implants
Authors: Downey Daniel F. , Chow Judy W. , Lerch Wilfried , Niess Juergen , Marcus Steven D. 
Published: April 2011

ABSTRACTIon implants of 1.0 keV 11B+, 5 keV BF 2+, and 2.0 keV As+ at a dose of IeI5/cm2 were rapid thermal annealed (RTA) in a STEAG AST-2800µ with varying percents of oxygen in N2, ranging from 0-lppm to 50,000 ppm to investigate the effects of low concentrations of oxygen during anneal. Sheet resistance (Rs), ellipsometry, SIMS, Tapered Groove Profilometry (TGP), and Scanning Force Microscopy (SFM) were employed to characterize these layers. For each of these implant cases, an optimal RTA condition is established which maximizes retained dose while still producing shallow junctions. As a function of O2 content, anneal temperature and implant condition, three regimes are observed that affect after anneal retained dose. These regimes are: dopant loss to the ambient resulting from etching of Si, dopant loss by out-diffusion from evaporation/chemical reactions, a capping regime that minimizes out-diffusion. In this later regime the dopant loss results from consumption into the RTA grown oxide. In addition, this paper also discusses oxidation enhanced diffusion (OED) and identifies its extent as a function of temperature and O2 content of the anneal for the three implant conditions investigated. For example, a 1.0 keV 11B+wafer annealed at 1050°C lOs in a controlled 33 ppm of O2 in N2 yields a SIMS junction depth 320 Å shallower than previously reported by others.