bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of Submicron, Narrow Size Distribution Spherical Zincite
Authors: Heistand Robert H. , Chia Yee-Ho 
Published: March 2011

ABSTRACTZincite has been produced by the controlled hydrolysis of an alkylzinc alkoxide (ethylzinc-t-butoxide) resulting in ∼0.2 μm spherical particles with a narrow size distribution consisting of 150 Å crystallites. The surface area is 30 m2/g. Variation of the concentration of the water drastically affects the particle and crystallite sizes. The results of a systematic study of the hydrolysis parameters are reported here.
Preparation of Ceramic Powders From Emulsions
Authors: Akinc Mufit , Richardson Kerry 
Published: March 2011

ABSTRACTYttrium oxide powders were prepared from water-in-oil type emulsions by loading the yttrium ions into the aqueous phase. Emulsions were characterized with respect to droplet size and distribution, emulsion type, and time and temperature stability. Precursor powders were obtained from the emulsions by evaporation of the aqueous phase in a hot oil bath. Powder characteristics, such as size, shape, composition, and sinterability as a function of procedural variables, were determined. The new technique appears to be practical and may be economically feasible.
Solid Phase Superheating During Picosecond Laser Melting of Gallium Arsenide
Authors: Von Der Linde D. , Fabricius N. , Danielzik B. , Bonkhofer T. 
Published: March 2011

AbstractThe velocity distributions of atoms evaporated from the surface of GaAs during laser heating with nanosecond and picosecond pulses are measured. The atomic velocities provide information about the surface temperature. For picosecond heating we observe a continuous transition of the temperature across the melting point, whereas for nanosecond heating the melting point is marked by a distinct plateau of the temperature curve. From these observations we conclude that the solid is strongly superheated during picosecond irradiation. A detailed analysis suggests superheating of typically a few hundred degrees above the melting point.
Transition-State Model for Entropy-Limited Freezing
Authors: Tsao J. Y. , Aziz M. J. , Peercy P. S. , Thompson M. O. 
Published: March 2011

AbstractA brief review is given of transition-state theory, both for the case of unimolecular reactions in the gas phase, and for reactions in condensed phases. An argument is made that, within the context of this theory, heterogeneous freezing in Si is limited to rates much lower than collision rates by the difference between the entropies of the solid and the liquid.
Time-Resolved and Post-Irradiation Studies of the Interaction of High-Power Pulsed Microwave Radiation with Silicon
Authors: James R. B. , Bolton P. R. , Alvarez R. A. , Valiga R. E. , Christie W. H. 
Published: March 2011

AbstractWe have measured the microwave-induced damage to the near-surface region of silicon for 1.9-μs pulses at a frequency of 2.856 GHz and a pulse power of up to 7.2 MW. Rectangular samples were irradiated in a test section of WR-284 waveguide that was filled with freon to a pressure of 30 psig. Incident, transmitted and reflected powers were monitored with directional couplers and fast diodes. The results of the time-resolved optical measurements show that the onset of surface damage is accompanied by a large increase in the reflected power. Examination of the irradiated surfaces shows that the degree of damage is greatest near the edges of the samples. Using secondary ion mass spectrometry to profile the implanted As, we find that the microwave pulses can melt the near-surface region of the material for pulse powers exceeding a threshold value.
Ion Emission During Low Fluence KrF Laser-Metal Interaction
Authors: Ying Q. Y. , Kwok H. S. 
Published: March 2011

AbstractA KrF laser was used to produce ions from an aluminum surface. The threshold energy fluence was found to be ∼30 mJ/cm2 which was lower than similar studies on the ablation of metals. The measured threshold however, was of the same order of magnitude for atomic desorption from semiconductor surfaces. This process can be used to perform surface analysis without ablation damage.
The Effect of Cooling Rate During Rapid Solidification on the Structure and Texture of NiTi
Authors: Pedraza A. J. , Godbole M. J. , Kenik E. A. , Pedraza D. F. , Lowndes D. H. 
Published: March 2011

AbstractA study has been conducted on the effects of increasing cooling rate during rapid solidification of NiTi upon the phases that are produced. The hammer and anvil rapid solidification technique and laser melting with a nanosecond excimer laser were used, which allow the cooling rate to be varied by three to four orders of magnitude. Although 1/3 {110} superlattice reflections are seen in the selected area diffraction (SAD) patterns of the splat quenched (SQ) specimens, x-ray diffraction analyses show the presence of only B2 phase and martensite. On the other hand, laser treatment (LT) of the specimens produces a layer that has a L10 structure with a slight monoclinic distortion. This phase can be envisaged as a small distortion of a B2 unit cell with a volume per atom ~3.3% lower than the equilibrium B2 phase. Also martensite is present in the layer. SQ alloys exhibit a marked {200} texture due to columnar growth opposite to the direction of heat extraction, while LT produces epitaxial regrowth of the melted layer. No substantial disordering is obtained in NiTi rapidly solidified alloys.
Crystallization of Amorphous 55wt%Cr-45wt%Ni Films Induced by 60 ns (0.694 μm) Single Laser Pulse
Authors: Ursu I. , Bîrjega M. I. , Constantin C. A. , Dinescu M. , Mihailescu I. N. , Pogrion N. Popescu , Ketskemety I. , Szill E. 
Published: March 2011

AbstractAmorphous 55wt%Cr-45wt%Ni films (60 nm thick) supported on EM copper grids were irradiated in air at normal incidence with a ruby laser (λ∼, 0.694 μm) through a ≈ 1.5 mm diameter diaphragm using one single laser pulse of 60 ns (FWHM) with fluences ranging from 120 to 540 J.m−2. The structure of the irradiated films is studied by TEM and TED. As a rule due to the appearance of thermal gradients between the centre and the mesh edge of the EM grid, the crystallization took place under various conditions of reaction from liquid phase, liquid melted layers , activated diffusion in solid state, to under threshold conditions for the development of the crystalline nuclei in the amorphous matrix. Periodic resonant and unreso-nant structures also developed in the liquid melted layers.
Laser Interactions with Optical Recording Materials
Authors: Marinero Ernesto E. 
Published: March 2011

AbstractLaser-material interactions are pivotal to optical storage technology. Laser quenching and thermomagnetic processes form the memory basis for approaches based on “phase-change” materials and magneto-optical alloys respectively. Recent progress in phase-change materials indicates that compound semiconductors as well as single element materials are characterized by fast crystallization times. In this work we review, utilizing time-resolved optical and conductivity probes, the melt-kinetics and glass formation processes in Te thin films and the laser-induced crystallization of amorphous GeTe. The latter studies are complemented by x-ray diffraction and TEM analysis. Results are also presented on time-resolved Kerr rotation studies to investigate the magnetic domain formation kinetics in thermo-magnetic recording. Material research problems facing laser interactions with optical recording materials will be discussed.
Nanosecond Dynamics of Excimer Laser Induced Thermal Decompositon of Thin Polymer Films
Authors: Wu X. D. , Dijkkamp D. , Gozdz A. S. , Venkatesan T. 
Published: March 2011

AbstractA novel method to study the effect of rapid heating on polymers is presented. Nanosecond time resolved reflectivity measurements of thermal decomposition of poly(3-butenyltrimethylsilane sulfone) (PBTMSS) and polymethylmetacrylate (PMMA) films spun on silicon wafers and irradiated by a pulsed excimer laser at 248 nm are reported. It was found that there exists a critical temperature for effective decomposition. The time scale for thermal decomposition is comparable with the time scales determined for photo-ablation processes. The results indicate that thermal effects are very important in the interaction between polymers and pulsed UV-lasers.
Nonequilibrium Interface Kinetics During Rapid Solidification
Authors: Aziz Michael J. 
Published: March 2011

AbstractThe deviations from local equilibrium at a rapidly moving solid-liquid interface are well documented. The fraction of solute atoms in the liquid at the interface that joins the crystal during rapid solidification approaches unity and the interface temperature drops. Experimental and theoretical work on impurity incorporation and interfacial undercooling is reviewed. Past and future experiments to test the theories are discussed.
Diffusion, Solubility and Segregation of Implanted Cu, Ag and Au in Amorphous Si
Authors: Jacobson D. C. , Elliman R. G. , Gibson J. M. , Olson G. L. , Poate J. M. , Williams J. S. 
Published: March 2011

AbstractThe diffusion of Cu, Ag and Au has been measured in implanted, amorphous Si, over the range 150–600° C. The diffusion coefficients are characterized by Arrhenius relationships with activation energies for Cu, Ag and Au of 1.25, 1.6 and 1.4 eV respectively. The solubility of Au in amorphous Si was measured to be 6 orders of magnitude greater than crystalline Si at a temperature of 515°C. The Cu, Ag and Au are segregated ahead of the moving amorphous-crystalline interface. The presence of Au can increase the velocity of the interface.
Formation Of Stable Point Defects in Ion-Implanted Si
Authors: Culbertson R. J. , Pennycook S. J. 
Published: March 2011

AbstractDouble doping of Si by ion implantation of both group V and group III dopants was studied. For the case of Sb as the group V dopant, both Sb and B could be maintained in solution after high temperature heat treatment at concentrations greatly exceeding their solubility limits. With Sb implantation alone, Sb diffusion takes place with a highly enhanced transient diffusion, followed by nucleation of self interstitials into loops at the projected range. In certain double-doped samples this projected range damage was eliminated. In the under-compensated B-Sb case, evidence of stable Sb-B pairs was obtained.
Neutralization Rates for Low-Energy Ions Scattered From Solid Surfaces
Authors: Eklund Elliott A. , Daley Richard S. , huang Judy H. , Williams R. Stanley 
Published: March 2011

AbstractCalculations of the angular distributions of scattered ions were used to simulate impact collision ion scattering spectrometry (ICISS) experiments. The calculations were performed first for 2–keV Na+ ions incident on the Pt(111) surface in the <112> azimuth. The fitting of these calculations to the experimental data provided information about the surface structure of the sample and the trajectories of the incident ions. The inclusion of a first-order decay model for Auger neutralization with the calculations for Na+ allowed the simulation of 2-keV Ne+ ions in the ICISS mode on the same Pt surface. From these simulations it was possible to extract the Auger neutralization halflife for Ne+, found to be 1.30 ± 0.10 femtoseconds.
Temperature Dependence of Amorphization above 10K in the CuTi Intermetallic Compound Under Electron Irradiation
Authors: Koike J. , Oluzzi D. E. , Meshii M. , Okamoto P. R. 
Published: March 2011

AbstractThe critical dose required to amorphize the crystalline compound CuTi during irradiation with 1 MeV electrons has been investigated from 10 to 288 K. The results show that above a critical temperature (Tc) of about 185 K, CuTi remains crystalline and only defect clusters are formed. Below Tc, amorphization occurs with no observable cluster formation. The critical dose for amorphization was found to be temperature dependent below Tc: as the irradiation temperature increases, a higher dose is required to induce amorphization. This observation supports the concept that Tc corresponds to the vacancy migration temperature. Below Tc, interstitial migration may contribute to the observed reduction in the amorphization rate with increasing temperature.
Smooth Silicide Formation by Ion Beam Mixing of Ti/Si-Layers
Authors: Kohlhof K. , Mantl S. , Stritzker B. 
Published: March 2011

AbstractIon beam mixing experiments of Ti-Si layers have been performed with Kr ions of 250 keV energy and doses ranging from 7 1015 to 7 1016 cm-2 at temperatures between liquid nitrogen temperature and 450°C. At substrate temperatures below 120°C no silicide formation could be detected. Only weak mixing at the Ti-Si interface is observed. At temperatures above 120°C the formation of TiSi2 could be verified by Rutherford backscattering and X-ray diffractometry. Layers of TiSi2 produced by ion beam mixing show smooth surfaces in contrast to those prepared by conventional furnace annealing. Those display rough surfaces and interfaces.
Ion Beam Induced Amorphization and Crystallization Processes in Silicon and GaAs
Authors: Elliman R. G. , Williams J. S. , Johnson S. T. , Nygren E. 
Published: March 2011

AbstractThin amorphous layers in crystalline Si and GaAs substates have been irradiated at selected temperatures with 1.5 MeV Ne+ ions to induce either epitaxial crystallization or amorphization. In Si, such irradiation can induce complete epitaxial crystallization of a 1000 A surface amorphous layer for temperatures typically >200°C whereas, at significantly lower temperatures, layer-by-layer amorphization results. Although epitaxial crystallization can also be stimulated in GaAs by ion irradiation at temperatures >65°C, the process is non-linear with ion dose and results in poor quality crystal growth for amorphous layers greater than a few hundred Angstroms in thickness. Layer-by-layer amorphization has not been observed in GaAs.
The Effect of Self-Implantation on the Interdiffusion in Amorphous Si/Ge Multilayers
Authors: Park B. , Spaepen F. , Poate J. M. , Jacobson D. C. 
Published: March 2011

AbstractArtificial amorphous Si/Ge multilayers of equiatomic average composition with a repeat length around 60 Å have been prepared by ion beam sputtering. Implantation with 29Si led to a decrease in the intensity of the X-ray diffraction peaks arising from the composition modulation, which could be used for an accurate measurement of the implantation-induced mixing distance. Subsequent annealing showed no difference between the interdiffusivity in an implanted and unimplanted sample.
Radiation Damage Induced Transient Enhanced Diffusion of Dopants in Silicon
Authors: Angelucci R. , Gabilli E. , Lotti R. , Negrini P. , Servidori M. , Solmi S. , Anderle M. 
Published: March 2011

AbstractTransient enhanced diffusion is observed for P, As and Sb as a consequence of the recovery of the damage created by a silicon dose below the amorphization threshold. The phenomenon results more pronounced for low temperature furnace heating than after rapid thermal annealing and for those elements having a larger component of interstitialcy diffusion mechanism.A close correlation was found between the trends of the anomalous dopant diffusion and the implant damage evolution analyzed by X-ray diffraction. This evolution takes place via interstitial cluster dissolution.
Dendritic Growth During Phase Transformation in Ni-Mo System Induced by Ion Beam
Authors: Liu B. X. , Huang L. J. , Shang C. H. 
Published: March 2011

AbstractMultilayered Ni-Mo films were irradiated by 200keV Xe ions at room temperature to various doses. The beam current density was confined to be less than lμA/cm2 to avoid overheating. The experimental evidences from X-ray diffraction, electrical resistivity, as well 4 as Rutherford Backscattering, indicate that a dose of 7 × 1014/cm2 was the critical one for uniform mixing of the layers and amorphous phase formation in Ni65 Mo35 films. Under this critical dose, various dendritic patterns were formed as revealed by bright field transmission electron microscopy. The microscopic mechanisms of the ion induced dendritic growth are attributed to the cluster formation and the aggregation of the formed clusters.
Radiation Defect-Induced Lattice Contraction of InP
Authors: Wie C. R. , Jones T. , Tombrello T. A. , Vreeland T. , Xiong F. , Zhu Z. , Burns G. , Dacol F. H. 
Published: March 2011

AbstractWe studied the lattice strain induced in the MeV ion bombarded InP crystals and the annealing behaviors of lattice strain, Raman line shift, and linewidth. The lattice spacing for the planes parallel to the surface decreases as a result of irradiation, and amounts to a strain of −0.061% for (100) face, −0.056% for (110) face, and −0.050% for (111) face for 15 MeV Cl bombarded samples to a dose of 1.25E15 ions/cm2. The negative lattice strain, Raman line shift, and line width completely recover at 450°C, and show a major recovery stage at 250°C – 350°C.
Study of Ion Implanted Copper Laser Mirrors by Spectroscopic Ellipsometry
Authors: Snyder P. G. , Massengale A. , Memarzadeh K. , Woollam J. A. , Ingram D. C. , Pronko P. P. 
Published: March 2011

AbstractImplantation with 400 keV Ag or Cu ions improves the near-surface microstructural quality and reflectance of diamond turned and mechanically polished flat copper laser mirrors. Spectroscopic ellipsometry is sensitive to changes in either the microscopic surface roughness, or in the nearsurface substrate void fraction, and both parameters are observed to change upon implantation. Substrate density as a function of ion fluence peaks at about 5 × 10 15cm-2. Low energy (300 eV) Ar ion implantation can cause either a reduction or increase in microscopic surface roughness, depending on fluence.
Growth -Front Modulation in Lamp Zone Melting of Si on SiO2
Authors: Dutartre D. , Bensahel D. , Haond M. 
Published: March 2011

AbstractWe present 3 techniques of defect localization we have studied in order to produce Silicon On Insulator films obtained by Lamp Zone Melting. They consist in a periodical variation of the thickness of either the oxide cap, or the polysilicon film, or the underlying oxide layer. We compare the crystallographic quality of the resulting films and in-situ observations of the solidification front for each structure.
Microstructural Characterization of High Dose Oxygen Implanted Silicon
Authors: Batstone J. L. , White Alice E. , Short K. T. , Gibson J. M. , Jacobson D. C. 
Published: March 2011

AbstractThe microstructure of oxygen implanted silicon for use in silicon-on- insulator technology has been examined by transmission electron microscopy. A variety of buried oxide layers prepared using oxygen doses below and above that required for stoichiometric SiO2formation have been studied. High resolution imaging in crosssection has revealed exceptionally flat Si-SiO2interfaces, comparable to the best thermally grown Si-SiO2interfaces. Examination of as-implanted material shows a complex interwoven crystalline/amorphous structure which evolves during high temperature (1350–1400° C) annealing into a buried oxide layer.
New DSPEG Approach to Improvement of SOS Using Low Dose Self-Implantations
Authors: Richmond Eliezer Dovid , Knudson Alvin R. , Kawayoshi H. 
Published: March 2011

AbstractA new approach is proposed for the material improvement of silicon-on-sapphire (SOS). This approach utilizes the phenomena that the defect elimination throughout the silicon layer depends on both the deep and shallow self-implantations of the double solid phase epitaxial growth (DSPEG) technique for SOS material improvement. The new aspects of this approach are that the deep implantation does not form an amorphous layer, and therefore the ion damage to the substrate is minimized eliminating Al autodoping of the silicon layer.
The Effect of Channel-Protect Oxide on Laser Recrystallized Silicon-on-insulator MOS devices.
Authors: Sritharan S. , Collins G. J. , Fukumoto J. , Szluk N. , Jones K. M. , Al-Jassim M. M. 
Published: March 2011

AbstractLatchup free lateral CMOS transistors with PMOS devices in the laser recrystallized silicon and the NMOS devices in the bulk silicon were fabricated. One micron thick field oxide isolates the PMOS devices in the recrystallized silicon from the NMOS devices in the bulk wafer. The seed area for recrystallization was used for the fabrication of the NMOS devices. An oxide layer of 0.1um thickness was used to protect the channel region of the NMOS devices during the laser recrystallization. The effect of this channel protect-oxide is discussed and the characteristics of the NMOS devices with and without the channel protect oxide are compared.
Defect States Induced by Rapid Thermal Annealing in Virgin or Implanted Czochralski-Grown Silicon
Authors: Remram M. , Barbier D. , Joly J.-F. , Laugier A. 
Published: March 2011

AbstractDefect state generation in either virgin or implanted CZ silicon has been investigated by means of capacitance transient spectroscopy (DLTS) after rapid thermal annealing (RTA), using an incoherent light furnace and variable cycle parameters. No electron traps were dectected with gold Schottky contacts made on virgin phosporous-doped silicon annealed for 5 sec at any temperature. On the otherhand 3 hole trap levels H1(0.45 eV), H2(0.29 eV) and H3(0.31 eV) have been observed in boron-doped silicon (Al Schottky contacts) after a 5 sec temperature plateau between 850 and 1050°C. Peak concentrations ranging from 1013 to 1014 cm−3 were measured after annealing at 1000°C for the three hole traps. By increasing the plateau duration up to 20 sec hole traps were no longer detected in boron-doped silicon. Furthermore in As+ or PF5+-implanted and rapidly annealed N+/P junctions the H3(0.31 eV) level was replaced by another hole trap H4(0.4 eV), which appeared within specific conditions (RTA parameters, implant dose and species). Moreover an electron trap E(0.55 eV) was only detected in the high dose As+-implanted junctions after annealing for 10 sec at 1100°C. The probable metallic origin of the observed defect states and the RTA parameter dependence of the hole trap concentrations suggest gettering and trapping in interstitial sites as possible mechanisms involved in RTA.
Laser-Induced Deposition of Gold
Authors: Baum Thomas H. 
Published: March 2011

AbstractThe laser-induced, vapor-phase deposition of gold metal from dimethyl-(2,4-pentanedionato) gold (III) and two fluorinated derivatives was examined by both photopyrolytic (LCVD) and photochemical modes of decomposition. High purity gold deposits are formed by LCVD with the rates of deposition being extremely vapor pressure dependent and thus, gold complex dependent. Photochemical deposition of gold patterns with 2 μm resolution can be achieved by irradiation of these complexes in the UV, but the deposited material is contaminated with carbon impurities.
Photo-CVD of Dielectric Films by a Microwave-Excited VUV Lamp
Authors: Tamagawa Kouichi , Hayashi Toshio , Komiya Souji 
Published: March 2011

AbstractSilicon nitride and oxide films have been formed using a photo-CVD apparatus with a microwave-excited VUV lamp. The lamp used was a D2 lamp or a rare gas resonance line lamp such as Xe and Kr. For the nitride film deposited at 320 °C, the BHF etching rate of the film, 40–70Å/min, is lower by less than one-tenth than that deposited using a conventional low-pressure Hg lamp, indicating formation of a high density film. The deposition rate has been enhanced dramatically from 13Å/min to 100Å/min by incorporating the photo-ionization assisted effect, which is brought about by an ionization of a substrate surface and by ions formed by collisions of reactant gases with photoelectrons and photo-ionized ions. The BHF etching rate of the oxide film is considerably lower than those formed using a Hg lamp and excimer lasers, and is similar to that using conventional PE-CVD. Conformal step coverage has been obtained for both the silicon nitride and oxide films.