bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of Laser Induced Backside Damage for Gettering Purposes
Authors: Eggermont G.E.J. , Allison D.F. , Gee S.A. , Ritz K.N. , Falster R.J. , Gibbons J.F. 
Published: March 2011

ABSTRACTA characterization of Q-switched Nd-YAG laser induced backside damage in various stages of a bipolar process is presented. TEM-analysis shows the occurence of microcracks, low angle boundaries and dislocations in as-irradiated wafers, of which the microcracks anneal out during an initial oxidation at 1050°C. The other damage is very stable and remains even after a heat treatment at 1200°C. This is quite in contrast with mechanically or Ar implantation induced backside damage, which anneal out completely at such high temperatures. Side effects of laser induced backside damage such as surface roughness and influence on wafer strength are found to be of no consequence within a limited range of laser pulse energy densities where the gettering efficiency is found to be very promising.
Pulsed Electron Beam Processing of Silicon
Authors: Greenwald Anton C. , Little Roger G. , Spitzer Mark B. , Wolfson Robert G. 
Published: March 2011

ABSTRACTContinued study [1] of pulsed electron beam annealing (PEBA) of thin silicon films deposited by LPCVD on silicon substrates has shown that a thin SiO2 interface remains intact during melt. PEBA of ion-implant damage in silicon has been shown to correlate dopant activation with melt depth. Also, PEBA was superior to thermal annealing of ion-implant damage in processing solar cells in some types of polycrystalline silicon material.
Calculations Pertaining to Raman Scattering During Laser Annealing of Ion-Implanted Silicon
Authors: Wood R. F. , Lowndes D. H. , Giles G. E. 
Published: March 2011

ABSTRACTCompaan and co-workers have reported the results of time-resolved optical experiments on ion-implanted silicon which they claim prove the melting model of pulsed laser annealing cannot be correct. These results concern the rapid onset of a Raman signal after a heating laser pulse, the simultaneous occurrence of a Raman signal and the high reflectivity phase characteristic of molten silicon, and the lattice temperature measured by the Raman Stokes/anti-Stokes intensity ratio. In this paper, we show by detailed numerical calculations with the melting model that there is, in fact, excellent agreement between the results of the calculations and the experimental results reported by Compaan and co-workers.
Studies of Laser Annealed GaAs (100), (110) and (111) Surfaces
Authors: Zehner D. M. , White C. W. , Appleton B. R. , Ownby G. W. 
Published: March 2011

ABSTRACTThe surface regions of (100), (110) and (111) oriented single crystals of GaAs have been investigated by the combine techniques of LEED, AES and RBS subsequent to their irradiation in UHV with the output of a Q–switched, ruby laser (0.15−0.8 J/cm2, 15 × 10−9 sec). Clean surfaces, as determined by AES, were obtained after Ar+ sputtering followed by laser irradiation. LEED observations indicate that the degree of disorder in the outermost surface layers remaining after irradiation depends on the crystal orientation. Although the relative intensities of Ga and As Auger transitions in spectra obtained from sputtered and laser annealed surfaces are similar, the differences in lineshape in these spectra of the M2,3M4,5M4,5 Ga Auger transition indicate that in the laser annealed case there are local regions which are nonstoichiometric. These observations are confirmed by RBS results, and this technique has been used to determine the stoichiometry and to characterize the damage in the subsurface region for all orientations.
Stability of Laser Annealed Contacts on Barium Titanate
Authors: Shukla V.N. , Narayan J. 
Published: March 2011

ABSTRACTLow resistance Ohmic contacts were produced by evaporating nickel and aluminum films on barium titanate substrates, and subsequently irradiating them with Q-switched ruby laser pulses (λ = 0.694 μm, τ = 15×10−9 s, pulse energy density 1.0 − 1.2 J cm−2). Stability and aging behavior of these contacts were comparable to those of conventional contacts, i.e. flame sprayed aluminum, In-Sn solder, fritted silver and electroless nickel under test conditions (ambient temperatures in air, in boiling water and organic liquids at 150°C, 100 psi).
Rapid Large Area Annealing of Ion-Implanted Si With Incoherent Light
Authors: Lischner D. J. , Celler G. K. 
Published: March 2011

ABSTRACTWe report an extremely rapid and efficient method for annealing ion-implanted wafers by transient irradiation with tungsten halogen lamps. Several 3-inch wafers are held in an inert atmosphere, thermally isolated from the water cooled base and separated by a quartz plate from the air cooled lamps, which can deliver in excess of 100 kW of power. Heating of the wafers up to 1200°C, or even to the melting point of Si, occurs within seconds. The cooling process can be equally rapid. The temperature is continuously monitored with a pyrometer. The radiative flux in the chamber is uniform within 5% over at least 500 cm 2; however, at temperatures 1200 °C radiative losses at the wafer perimeter may cause crystalline slip if proper countermeasures are not taken.
Optimised Multi-Scan H-Beam Annealing Of Mos Devices
Authors: Pollard C J , Glaccum A E , Speight J D 
Published: March 2011

ABSTRACTThe optimum e-beam anneal conditions for damage free wafer annealing, implant activation uniformity across 3 inch wafers and low dose boron activation have been investigated with reference to the needs of MOS device processing. Some effects of e-beam annealing on MOS gate dielectrics are reported.
Glancing Angle X-Ray Analysis of Titanium Copper Compound Formations
Authors: Psaras P. A. , Gupta D. 
Published: March 2011

AbstractTitanium copper compound formations have been studied via Seeman Bohlin x-ray diffractometry and Rutherford backscattering spectrometry. The heat treatment temperature range was 350°C to 475°C and th heat treatment times ranged from 0 to 240 minutes. Tetragonal gamma TiCu formed first at ˜350°C and was sequentially followed by orthorhombic TiCu3 at ˜400°C. From Rutherford backscattering spectrometry analysis it was concluded that the second TiCu3 compound deviated from ideal stoichiometry to a nonstoichiometric Ti0.88Cu3.12 composition
Polymer-Polymer Interdiffusion
Authors: Kramer Edward J. 
Published: March 2011

AbstractInterdiffusion of polymer chains plays an important role in establishing good adhesion at polymer interfaces as well as in the kinetics of phase separation and mixing in polymer blends. Reptation, a process in which a given linear chain crawls along a primitive path defined by the topological constraints due to the surrounding chains, is thought to be the most important diffusion mechanism. A reptating chain of Volecular weight M should have a tracer diffusion coefficient given by D =DR =Do M−2, where D depends on the Rouse mobility of the chain and an entang ement molecular weight, Me. Because the topological constraints are assumed to be fixed, DR is independent of the molecular weight P of the polymer into which the M-chains are diffusing. In principle however if M is large enough and P is small enough the M-chain can diffuse by rearrangement of the P-chains surrounding it, a process called constraint release. The D for this process, DCR= αCRDoMe2/(MP3), where αCR is a constant approximately equal to 13, increases strongly with decreasing P. Recent experimental results, which give evidence for both reptation and constraint release, will be reviewed. These results have important implications for the diffusion of nonlinear polymer chains, e.g. stars and rings.
Surface Chemical Studies of Oxides and Nitrides
Authors: Pantano Carlo G. 
Published: March 2011

AbstractThe application of surface analysis techniques for the study of fundamental surface and thin film phenomena is described. The topics covered relate to the processing and fabrication of electronic packages and include: evaporation/condensation during the thermal processing of glasses, hydration of glass surfaces and thin films, nitridation of silica films, diffusion behavior in oxides at low temperature, and impurity segregation in thin films. A wide variety of surface analytical methods are exemplified including Auger electron spectroscopy (AES), ion-scattering spectroscopy (ISS), nuclear reaction analysis (NRA), secondary-ion mass spectroscopy (SIMS) and x-ray photoelectron spectroscopy (XPS).
Ceramic-Metal Interactions
Authors: Klomp J. T. 
Published: March 2011

AbstractCeramic-metal interactions are on the basis of a variety of technologies covering the fields of materials production as in ceramic-metal composites and the techniques of joining ceramic to metal. The physics and chemistry of interactions at ceramic-metal interfaces are still the subject of intensive studies not only from a scientific point of view but also for technological reasons because the emergence of new ceramic materials calls for insight into the interactions of these materials with metals. In this paper the mechanisms of ceramic-metal interactions are reviewed against the background of the technology and some extensions of existing interaction models are given.
Eutectic Bonding of Copper to Ceramics
Authors: Wittmer Marc 
Published: March 2011

AbstractEutectic bonding of copper to ceramics makes use of a liquid eutectic between copper and oxygen at 1065°C which wets oxide ceramics very well. Upon solidification of the eutectic melt a very strong bond is established which has a strength of about 5×107N/m2. The excellent bond strength gives this technique important applications in electronic packaging and mechanical engineering.
Directly Bonded Copper Metallization of AℓN Substrates for Power Hybrids
Authors: Kluge-Weiss Petra , Gobrecht Jens 
Published: March 2011

AbstractAluminum nitride (AℓN) ceramic is emerging as an attractive substrate material for high performance heat sinking in hybrid circuits be -cause of its high thermal conductivity. We report on the application of the direct bonding technique for Cu on AℓN substrates. For successful bonds, the surface of the AℓN has to be oxidized. Oxidation rates are reported and the oxide morphology is analyzed. The peel strength of the Cu sheet depends on oxide thickness, growth method and Cu-type used. Under optimum conditions the peel strength exceeds 50 N/cm. A detailed analysis using optical microscopy as well as SEM, STEM, EDX, and electron diffraction techniques of the AℓN/Aℓ2O3/Cu interface is carried out.
Casting Ceramic-Polymer Sheets
Authors: Shanefield Daniel J. 
Published: March 2011

AbstractThin ceramic structures can be efficiently formed by the tape casting process, using a doctor blade for thickness control. A concentrated suspension of the ceramic precursor powder is made in a solvent system, with a polymeric binder, a dispersing agent, and other additives. For high performance ceramic applications, a non-aqueous solvent is generally preferred. The physical chemistry background leading to this choice is discussed, particularly in regard to the competing adsorptions of solvent, dispersant, and binder. Glyceryl trioleate is shown to be a useful dispersant for such systems, allowing dense compacts to be achieved, even with submicron particle sizes. Thus a refractory powder can be fired to nearly theoretical density at practical temperatures.
A Raman Scattering Study of the Temperature Dependence of Boroxol Ring Clusters in B2 O3-GeO2 and B2 O3-GeO2-SiO2 Glasses.
Authors: Chakraborty I. N. , Condrate R. A. 
Published: March 2011

AbstractThis Raman study indicates that the boroxol ring concentrations for glasses in the B2 O3-GeO2 and B2 O3-GeO2-SiO2 systems are dependent upon temperature and composition. Ring breakage and formation occur well below Tg. An Arrhenius plot of intensity data for borogermanate g glass indicates that the heat of ring rupture is ca. 7.7 Kcal/mole. The boroxol ring concentrations in various glasses were also investigated at room temperature after various heat treatments. The structural interpretation from Raman scattering data was compared with that from IR data.
Recent Advances in Huang Diffuse Scattering
Authors: Ehrhart P. 
Published: March 2011

AbstractMeasurements of the diffuse X-ray (or neutron) scattering allow the detailed investigation of point defects in crystalline solids. The method can be applied for defect sizes ranging from isolated point defects up to large dislocation loops. The diffuse scattering intensity close to the Bragg reflections, Huang Diffuse Scattering and Asymptotic Diffuse Scattering, is of special interest as the intensities from lattice distorting defects are high and the scattering theory is most straightforward for this region of the reciprocal lattice. After a short introduction to the theoretical background and to the experimental techniques the capabilities and limitations of the method will be demonstrated with examples of experimental results. i) The structure of interstitial atoms has been investigated for low temperature irradiated crystals and for metals with interstitially dissolved solute atoms. ii) The mobility and growth of interstitial agglomerates during annealing stage II of irradiated metals is discussed. The influence of impurities on the cluster growth is demonstrated for the example of Nibase alloys. iii) Defect clusters and defect distributions within cascades as observed after different types of irradiations are discussed.
The Effect of Adsorbeb Oxygen Ions on the Inelastic Scattering of Photo-Electrons at the Metal-Vacuum Interface
Authors: Pong W. , Brandt D. , He Z. X. , Imaino W. 
Published: March 2011

AbstractMeasurements of uv photoemission from evaporated aluminum films were made at photon energies 7.7–11 eV as a function of time after film deposition. Evidence of the initial stage of chemisorption of oxygen can be seen in the uv photoelectron spectra. The spectra taken immediately after film deposition showed a smooth energy distribution characteristic of clean aluminum. Structure in the spectra was found to appear at approximately 60 minutes after deposition at 10−9 Torr. Three noticeable features were observed at 1.0, 1.3, and 2.5 eV above the vacuum level. They appeared stationary with increasing photon energy. The structure can be attributed to inelastic scattering of photoelectrons into resonant states associated with oxygen ions on the metal surface. The energy levels of the calculated resonant states of a helium-like system are compared with the energy of the observed structure. The agreement suggests that there are adsorbed 0− ions to which photoelectrons can be scattered at the metal-vacuum interface.
X-Ray Diffraction Applied to the Study of Defects in Surfaces
Authors: Robinson I. K. , D'amico K. L. 
Published: March 2011

AbstractThe role of x-ray diffraction in characterising defects in crystals is reviewed briefly. It is most sensitive to the presence of plane defects which destroy the long-range order. The same argument is shown to apply to line defects in surface structures. Two recent glancing incidence x-ray diffraction experiments provide contrasting examples: randomly distributed steps are found in the Au(110) reconstructed surface, while regular arrays of domain walls modify certain phases of krypton monolayers physisorbed on graphite substrates.
Characterization of Surface Defect Structure by Low Energy Electron Diffraction
Authors: Wendelken J. F. , Wang G. -C. , Pimbley J. M. , Lu T. -M. 
Published: March 2011

AbstractLow energy electron diffraction is a surface sensitive tool which is most widely used for the determination of surface symmetries and equilibrium atomic positions. Experimental and theoretical advances made in the past five years make it possible now to use LEED also for the characterization of a wide variety of surface defect structures. In this paper a variety of experimental results involving analysis of diffracted electron beam shapes as a function of primary electron beam energy, adsorbate coverage, crystal tem-perature and ordering time are presented. These experimental results coupled with kinematic theory, allow the determination of step density, size and shape of reconstruction domains and overlayer islands, island size distribution in an overlayer during growth, and the mode of growth.
An HVEM Investigation of In-Situ, Self-Ion Damage in Iron at 40 and 300 K
Authors: Kirk M. A. , Robertson I. M. , King Wayne E. , Ryan E. A. , Philippides A. 
Published: March 2011

AbstractBombardments of iron (commercially pure) with self-ions having energies of 50 and 100 keV were performed in–situ in a High–Voltage Electron Microscope at temperatures of 40 and 300 K. The resulting damage microstructures were examined at the irradiation temperature in the HVEM using 200, 300, 500 and 1000 keV electrons (damage threshold in Fe is ˜330 keV). Dislocation loop densities were measured as functions of ion dose, ion energy, irradiation temperature, electron dose (500 keV), and step annealing to room temperature. Loop geometries, size distributions, and nature (interstitial or vacancy) were also determined.
Factors Affecting Spatial Resolution for Compositional Analysis in Stem
Authors: Sande John B. Vander , Garratt-Reed Anthony J. 
Published: March 2011

AbstractThis paper discusses the application of the scanning transmission electron microscope (STEM) to the detection of segregation at interfaces via the monitoring of X-rays generated when the incident electrons interact with the segregant. Issues of spatial resolution and minimum detectable concentration are discussed. Specific examples, emphasizing the importance of probe size, sample thickness, and sample orientation, are presented.
VUV Synchrotron Light as a Technique for Studying the Interface Quality and Properties of Thin Overlayers
Authors: Ruckman M. W. , Murgai V. , Strongin Myron 
Published: March 2011

AbstractThe measurements presented here show the value of synchrotron light for determining both the electronic structure of overlayers, and the physical nature of the overlayer-substrate interface. A comparison is given between deposited layers and thermally stabilized layers. Estimates are also made of the bonding energy between the overlayer and substrate.
Comparison of Performance of an Analytical Electron Microscope at 300 and 100 kV
Authors: Bentley J. , Kenik E. A. , Angelini P. , Fisher A. T. , Sklad P. S. , Lehman G. L. , Horton J. A. 
Published: March 2011

AbstractPreliminary results on the performance of an analytical electron microscope (AEM) operating at 300 kV have been obtained and compared with the performance at 100 kV. Some features of the anticipated improvements for transmission electron microscopy (TEM) imaging, convergent beam electron diffraction (CBED), energy dispersive X-ray spectroscopy (EDS), and electron energy loss spectroscopy (EELS) have been studied from the aspect of materials science applications. The electron microscope used was a Philips EM430T operated with a LaB6 cathode and equipped with EDAX 9100/70 EDS and Gatan 607 EELS systems.
The Effect of Temperature on Defect Production in Copper Doped with Beryllium
Authors: Baily A. C. , King Wayne E. , Mrkle K. L. , Meshii M. 
Published: March 2011

AbstractThe effect of temperature on radiation-induced defect production was investigated in Cu single crystal films doped with ∼ 100 ppm Be. Frenkel pair production was determined at 55K and 190K as a function of electron energy and incident beam direction using in situ electrical resistivity measurements in the high voltage electron microscope. The crystallographic anisotropy of defect production was found to be considerably greater for irradiations at 55K than for irradiations below 10K. This difference is related largely to an observed anisotropy in the stage I defect recovery. It was found in isochronal annealing experiments after irradiation nearthreshold that the resistivity remaining after stage I was nearly twice as large for recoils along <110> as compared to <100>.
Characterization of Atomic Defects and Their Aggregates Using Positron Annihilation Spectroscopy
Authors: Siegel R. W. , Fluss M. J. , Smedskjaer L. C. 
Published: March 2011

AbstractPositrons localize in trapped states at a variety of defect sites in solids, from which they subsequently annihilate with unique observable characteristics. As such, the positron is a valuable probe for the study of these defects. Positron annihilation spectroscopy (PAS) has made significant contributions in recent years to the determination of atomic defect properties in metals and alloys, and in molecular solids as well. It has also been used extensively in the monitoring and characterization of vacancy-like microstructure development, as occurs during post-irradiation annealing. The characterization of defects using PAS is selectively reviewed and some possibilities for using the positron as a localized probe of the atomic and electronic structure of atomic defects and their aggregates are discussed.
On the Properties of Ultra High Strength Concrete With Particular Reference to Heat of Hydration
Authors: Aarsleff Leif , Bredal-Jorgensen Jorn , Poulsen Ervin 
Published: March 2011

AbstractIt has been observed that the heat of hydration for concrete under practical conditions not only depends on the type of cement and the content of cement and silica fume in the concrete but also depends on the w/c-ratio of the concrete. On.microscopic examination of concrete having low w/c-ratio it has been observed that the cement compounds are left partly unhydrated. However, the unhydrated cement compounds exist for all values of the w/c-ratio, but appear to increase with decreasing value of the w/c-ratio, particularly when w/c < 0.35.This fact wIll influence the present way of estimating the heat of hydration when a thermal stress analysis is to be carried out for an ultra high strength concrete in order to prevent the concrete from crackling due to temperature differences across a massive cross-section.The tests are carried out with concrete having a compression strength greater than 100 MPa (∼ 14,000 psi). In order to obtain samples drilled from the same casting for compression tests, microscopic investigatlon, penetration tests and freezing/thawing-investigation rather large specimens are used. A very effective insulation of the concrete is provided, and the temperature of the concrete is recorded by thermo-couples.The structure of the cement paste is studied using petrographical examination of thin-sections and polished samples. The tests on penetration and freezing/thawing are not dealt with in this paper.
Microstructure as A Tool for Proportioning High-Strength Concrete Mixes
Authors: Hester Weston T. 
Published: March 2011

AbstractUntil relatively recently, concrete mix materials were selected and proportioned on the basis of certain general principles established through empirical tests, past experience with similar materials, and published tables. Increasingly, however, wc. need to produce high-strength concretes with what has been considered sub-optimal or even marginal quality materials. And, whereas in the past we could afford to achieve high strengths at age 28 or 56 days, there is much greater emphasis now on achieving strengths in excess of 8,000 psi in 24 hours or less.In response to these new demands for high-strength concretes, the concrete industry is setting aside many of the traditional methods for selecting and proportioning materials. Now, mix materials are selected deliberately for the characterisitics of their microstructure (e.g., the mineralogy and particularly crystal structure of the aggregates), and are proportioned to optimize the microstructure of the concrete.In this paper the author illustrates how the characteristics of a material's microstructure are used as tools in selecting and proportioning mix materials. The significance of the microstructure of the aggregate particles, mortar-aggregate interface, and mortar are discussed in detail.