bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Influence of Tiw Barrier Layer on Reliability of AlCu and AlSiCu Interconnects
Authors: Kordic S. , Wolters R.A.M. , Augur R.A. , Dirks A.G. 
Published: April 2011

AbstractThe influence of a TiW barrier layer on the stress-voiding behavior of AlCu and AlSiCu interconnects is investigated. The results are compared to the same alloys deposited on SiO2- In both cases, AlCu exhibits a notably better voiding behavior compared to AlSiCu. In the case in which the alloys are directly deposited on the TiW barrier without breaking vacuum between TiW and Al(Si)Cu depositions, a significant improvement of the voiding behavior of both alloys is observed. Compared to AlCu, AlSiCu shows worse voiding behavior due to the presence of Si precipitates, which introduce significant extra dislocations and defects in the Al grains. These dislocations and defects are diffusion paths which assist stress relaxation and void formation. In the presence of a TiW barrier part of the Si content of the AlSiCu is consumed during the anneal by the Al-TiW interface, which results in a decreased number of dislocations and defects within the Al grains, and an improved voiding behavior compared to AlSiCu on SiO2-Furthermore, W and Ti diffuse into the grain boundaries of both alloys. The presence of W and Ti in the grain boundaries reduces the amount of Cu depletion from within the grains, which makes both alloys more resistant to stress voiding. The above is supported by Auger and TEM results. The electromigration results of the alloys in question are presented. These show that also with respect to electromigration AlCu is the preferred alloy both on TiW and SiO2.
Metallization Systems on Cvd-Diamond Substrates for Application in Multichip Modules
Authors: Brown W. D. , Naseem H. A. , Malshe A. P. , Glezen J. H. , Hinshaw W. D. 
Published: April 2011

AbstractBecause of its high thermal conductivity, free-standing CVD-diamond is an extremely attractive material for application as the substrate in multichip modules (MCMs). However, this material does present some technological challenges, one being the development of reliable metallization systems. In this work, adherent metallization systems, such as Au/Ti, Au/Ti-W, Au/Ni-Cr, Au/Cr and Cu/Cr have been produced at low temperatures. Thin adhesion/seed metal layers were deposited using sputtering and evaporation techniques. Gold and copper metallization of several microns thickness was accomplished by electroplating over the thin metal layer. Post-deposition annealing of both the adhesion/seed layer and plated metallization systems were performed at temperatures up to 500°C in an effort to enhance adhesion and determine the impact of subsequent high temperature operations on reliability issues such as intermetallic diffusion, delamination, and the impact of surface microcavities. Extremely adherent Au/Cr and Cu/Cr metallization systems appropriate for use in MCM technology were developed.
Formation of Ultra-Thin Silicon Oxynitride Films by Low-Energy Nitrogen Implantation.
Authors: Diniz J. A. , Tatsch P. J. , Kretly L. C. , Queiroz J. E. C. , Godoy Fo J. 
Published: April 2011

AbstractOxynitrides (SiOxNy) have been used as gate insulators for submicron devices [1]. The present work reports the oxynitride formation at SiO2/Si structure by N2+ implantation at low energies. Si substrates were implanted with N2+ ion beams (energy = 5.6 keV and dose =1×10 ions/cm2), annealed at 950°C for 30 min in N2 ambient, oxidized at 950°C in O2 + 1% TCE environment and annealed at 950°C for 30 min in N2. After these process steps, the oxynitride formation was investigated by FTIR, SIMS and ellipsometric analysis. These physical characterizations revealed the presence of Si-0 and Si-N bonds. The film thicknesses and refractive indexes were 7 nm and 1.62, respectively. The dielectric constant = 4.39 and effective charge density = 7xl010 cm–2 were determined by C-V, indicating that the SiOxNy films formed are suitable gate insulators for MOS devices.
Persistent Photoconductivity Study on Ion Irradiated Carbon Films
Authors: Bhattacharyya Somnath , Kanjilal D. , Subramanyam S.V. 
Published: April 2011

AbstractConducting carbon films are irradiated by high energy ion beam and persistent photoconductivity has been found from the irradiated samples. A complex distribution of traps created mostly by random displacement of carbon atoms by energetic ion beam from its polymeric matrix showed a persistent photoconductivity at low temperatures down to 50K. From the photo decay constants and the magnitude of photocurrent the density of traps and the corresponding activation energies have been calculated.
Ion Beam Modification of PVDC and Pe Polymers
Authors: Evelyn A. L. , Ila D. , Fisher J. , Poker D. B. 
Published: April 2011

AbstractThe electronic and nuclear stopping effects produced by MeV ion bombardment in polyvinylidine chloride (PVDC) and polyethylene (PE) are separated by stacking thin films of the polymers. The resulting multi-layer laminates of each polymer were bombarded with 3.5 MeV alpha particles. The energy of the incident ions was selected, using TRIM, such that the first layers experienced most of the effects of the electronic energy deposited and the last layers received most of the effects of the nuclear stopping power. The changes in the conductance and the chemical structure of each layer were measured by direct resistivity measurements and Raman microprobe analysis.
Mev Ion Beam Induced Index of Refraction Changes in Layered GaAs/AlGaAs Waveguides
Authors: Taylor T. , Ila D. , Zimmerman R. L. , Ashley P. R. , Poker D. B. 
Published: April 2011

AbstractPreviously, we showed that localized optical modifications could be produced without subsequent post thermal annealing in selectively masked planar GaAs/Al 4Ga6As waveguide structures using 10 MeV oxygen ions. In our present investigation, irradiation experiments were performed on masked GaAs/Al 4Ga6As waveguide samples at 298 K using 10 MeV oxygen and 8 MeV carbon ions. The two ion incident energies were chosen to yield the maximum electronic stopping power near the interface septing the top cladding layer and the guiding layer. This localized modification process emphasizes the crucial role that the electronic energy transfer plays on the degree to which the refractive index of the guiding layer is altered. Propagation loss measurements on the fabricated channel waveguides were performed by end fire coupling a laser diode source at a wavelength of 1.3 μm. Observation of the extracted propagation loss values reveal that further optimization of the ion beam pmeters are required before practical applications can be achieved. The relative efficiency of the various ions to induce optically altered regions which serve as lateral confinement barriers of laser light shows that this fabrication process is sensitive to the ion beam current.
Vibrational and Electronic Transition in InAs Quantum Dots Formed by Sequential Implantation of in and as in a-SiO2
Authors: Ueda A. , Henderson D.O. , Mu R. , Tung Y.-S. , Hall C. , Zhu Jane G. , White C.W. , Zuhr R.A. 
Published: April 2011

AbstractThe optical, structural, and thermodynamic properties of materials can be changed by reducing their dimensions. We sequentially implanted In and As into fused silica windows in order to investigate the formation and properties of InAs nano-particles. The UV/VIS/NIR, FTIR in mid-IR, and far-IR spectroscopy were mainly used to study the change in electronic transitions and in vibrational modes (phonons) of the nanoparticle InAs. The phonons can be confined to the surface of nanoparticles and have frequencies falling between the transverse and longitudinal optical modes of the bulk material. Thermal annealing developed the formation of InAs quantum dots from as-implanted In+As system. At a certain annealing temperature, we observed a change in UV/VIS transmission spectra and IR reflectance spectra indicating the formation of InAs quantum dots. This is particularly evident from the absorption in the IR, and surface phonon bands are observed confirming the presence of quantum confined InAs.
Crystalline Structure and Composition of Tin Oxide Film Grown by Reactive Ion Assisted Deposition as a Function of Average Diradiating Energy
Authors: Choi W.K. , Song S.K. , Cho J.S. , Jung H.-J. , Koh S.K. 
Published: April 2011

AbstractTin oxide films with highly preferred orientation along <101 axis were grown on Si(100) substrate by using reactive ion assisted deposition method. The impinging average ion energy per depositing Sn atom was changed from 10 to 100 eV/atom. Oxygen content in the deposited tin oxide films increased as average impinging ion energy were raised. The maximum XRD peak intensity appeared when the average energy of about 50 eV/atom was applied. From quantitative Auger electron spectroscopy, characteristic transitional Auger peaks of Sn MNN were shifted to lower kinetic energies as much as 4 ∼ 6±1.0 eV as the Sn4+ component became dominant in the deposited tin oxide films. On the basis of a tin 3d core level spectra analysis by XPS, it was determined that a sizable chemical shift of 1.0±0.02 eV occurred between stannous tin(Sn2+:SnO) and stannic tin(Sn4+:SnO2). The optical transmittance was also measured in the wavelength range from 200 to 800 nm for tin oxide films deposited on BK7 glass substrate.
Carbon, Nitrogen, and Oxygen Ion Implantation of Stainless Steel
Authors: Rej D.J. , Gavrilov N.V. , Emlin D. , Henins I. , Kern K. , Kurennykh T. , Mizgulin V.N. , Munson C.P. , Nastasi M. , Scheuer J.T. , Vykhodets V. , Walter K. C. 
Published: April 2011

AbstractIon implantation experiments of C, N and O into stainless steel have been performed with beam-line and plasma source ion implantation methods. Acceleration voltages are varied between 27 and 50 kV, with pulsed ion current densities between 1 and 10 mA/cm2. Implanted doses range from 0.5 to 3×1018cm-2, while workpiece temperatures are maintained between 25 and 800°C. The implant concentration profiles, microstructure and surface mechanical properties of the implanted materials are reported.
Effect of Coherency Stresses on the Stability of Lamellar (α2+γ) Titanium Aluminides
Authors: Appel F. , Christoph U. , Lorenz U. , Wagner D R. 
Published: April 2011

AbstractTwo phase titanium aluminides with a lamellar microstructure of the intermetallic phases α2(Ti3Al) and γ (TiAl) are being developed for high temperature structural applications. Due to differences in lattice parameters and crystal structure, coherency stresses and mismatch structures occur at various types of semicoherent interfaces present in the material. The implications of these structural features on the stability of lamellar microstructures were studied by TEM in situ heating experiments. The investigations revealed that the lamellar interfaces serve as sources for perfect and twinning dislocations. The results will be discussed with respect to the observed degradation of the strength properties of the two phase alloys in the intended service temperature range of 900- 1000 K.
Effects of Strain on the Electronic and Vibrational Properties of Semiconductors and Semiconductor Microstructures
Authors: Pollak Fred H. 
Published: April 2011

AbstractThis paper will review the effects of strain on the electronic and vibrational properties of semiconductors and semiconductor microstructures. Topics to be discussed include deformation potential theory for electronic states () and vibrational modes () of bulk material, polarization effects, the influence of strain (internal and external) on quantum states (band alignments, light-and heavy-hole splittings, polarization effects), piezoelectric effect, strain relaxation, etc. Also various measurement techniques will be mentioned. Selected examples of various phenomenon will be given, including some new and novel device applications.
Influence Of Growth Parameters On Interface Broadening In Mbe-Grown Interfaces: A Non Destructive Study By Magneto-Optics
Authors: Grieshaber W. , Haury A. , Cibert J. , d'Aubigné Y. Merle , Wasiela A. 
Published: April 2011

AbstractWe present a detailed study of the influence of growth parameters on the broadening of CdTe-CdMnTe interfaces using a new magneto-optical technique [1,2] in MBE-grown quantum wells and superlattices. For growth temperatures up to about 300°C the Mn content decreases exponentially at the CdTe on CdMnTe interface and conversely the Cd one decreases exponentially at the CdMnTe on CdTe interface. At temperatures exceeding 300°C an additional broadening takes place which acts equally on both interfaces. Growth interruptions and modified flux stoechiometry do not exhibit significant influence on the broadening.
Fourier Transform Analysis of Franz-Keldysh Oscillations Observed in Electromodulation Spectra
Authors: Holm R. T. , Glembocki O. J. , Tuchman J. A. 
Published: April 2011

AbstractDiscrete Fourier transform (DFr) techniques have been applied to the analysis of the Franz-Keldysh oscillations used in determining electric fields. It is shown that the DFT can be applied to a wide range of EM line shapes and that it can yield accurate results for the electric fields in the case where one field is present in the sample. For cases where there are contributions to the EM spectrum from either two electric fields or two degenerate transitions, such as excitations originating from light- and heavy-hole valence bands, care must be applied in extracting the field from the lower intensity DF” peak. The window used to obtain the DFT influences the peak position of lower intensity DFT peak and thus can lead to spurious shifts of the line.
Experimental Study of the Liquid-Glass Transition in an Inorganic Polymer Li0.5Na0.5PO3
Authors: Rufflé B. , Beaufils S. , Délugeard Y. , Coddens G. , Etrillard J. , Toudic B. , Bertault M. , Even J. , Gallier J. , Écolivet C. 
Published: April 2011

ABSTRACTNew experimental results obtained with various techniques on a less-studied glass-forming system are presented. At low frequency, a secondary βslow-process, decoupled from the viscous flow, is observed by 3 1P NMR. Raman scattering spectra and coherent neutron scattering spectra has been obtained in wide frequency and temperature ranges showing the same qualitative features for the Boson peak while the quasielastic contribution seems to differ markedly.
Formation of Colloidal Copper Hydroxides and Oxides Biopolymeric Interfaces
Authors: Hinze U. , Thies M. , Paradies H. H. 
Published: April 2011

ABSTRACTLight sensitive colloidal particles of copper hydrous oxides were prepared at interfaces of exopolymeric materials. Dislike copper oxide or hydroxide nanoclusters were obtained which might be useful as p-type semiconductors. The colloidal Cu2O xH2O and Cu(OH)2 particles reveal fractal dimensions of D = 2.15 ±0.05 for Cu(OH)2 and D= 1.75 ±0.07 for Cu2O xH20.
Zirconia Solubility in Boroaluminosilicate Glass
Authors: Raman S. V. , Bopp R. , Batcheller T. A. , Yan Q. 
Published: April 2011

AbstractIn the Idaho Chemical Processing Plant (ICPP) waste streams, zirconia is often the waste load limiting species. It modifies the glass network, enhances durability, increases viscosity and induces crystallization. The limits of its dissolution in boroaluminosilicate glass, with magnesia and soda additions were experimentally determined. A ternary compositional surface is evolved to present the isothermal regimes of liquid, liquid+zircon, liquid+forsterite, and liquid phase sintered ceramic. The potential of partitioning the transuranics, transition elements and solutes in these regimes is discussed. The visible Raman spectroscopic results are presented to elucidate the dependence among glass composition, structure and chemical durability.
Electrochemical Treatment of Mixed and Hazardous Waste
Authors: Dziewinski J. , Marczak S. , Nuttall E. , Smith W. 
Published: April 2011

AbstractLos Alamos National Laboratory (LANL) and The University of New Mexico are jointly developing an electrochemical process for treating hazardous and radioactive wastes. The wastes treatable by the process include toxic metal solutions, cyanide solutions, and various organic wastes that may contain chlorinated organic compounds. The main component of the process is a stack of electrolytic cells with peripheral equipment such as a rectifier, feed system, tanks with feed and treated solutions, and a gas-venting system. During the treatment, toxic metals are deposited on the cathode, cyanides are oxidized on the anode, and organic compounds are anodically oxidized by direct or mediated electrooxidation, depending on their type. Bench scale experimental studies have confirmed the feasibility of applying electrochemical systems to processing of a great variety of hazardous and mixed wastes. The operating parameters have been defined for different waste compositions using surrogate wastes. Mixed wastes are currently treated at bench scale as part of the treatability study.
Ultra-High-Tg Chromophoric Polyimides and Polyureas as High-Performance Nonlinear Optical Materials
Authors: Geng Lifeng , Wang Jiafu , Marks Tobin J. , Lin Weiping , Zhou Haitian , Lunquist Paul M. , Wong George K. 
Published: April 2011

ABSTRACTThree approaches to the construction of high-Tg polyimides and polyureas as second-order NLO materials are discussed. In the first approach, copolymerization of bismaleimides with o,o‚-diallylbisphenol-A followed by functionalization with high-β NLO chromophores using a Mitsunobu procedure yields, after poling and curing, a series of heavily crosslinked chromophoric polyimides with Tg values as high as 320°C and partially resonant χ(2) responses as high as 1.0×10-7 esu (42 pm/V at 1064 nm, 1.17 eV). In the second two approaches, copolymerization of the chromophore 4,5-bis(4‚-aminophenyl)-2-(4„- nitrophenyl)imidazole with bismaleimides or diisocyanates yields polyimides and polyureas with Tg values as high as 292°C and partially resonant χ(2)values as high as 0.62× 10-7 esu(25 pm/V at 1064 nm). It is found that careful attention to the details of curing and crosslinking during poling results in NLO- active matrices exhibiting negligible decay in ( on aging in air at 100°C for periods of 1,000-4,000 h. The imidazole based materials exhibit only about 10% χ(2) decay on aging for 100 h at 200°C under N2.
Optical Characterization of Binuclear Phthalocyanines
Authors: Sokoloff Jason P. , Yanagi Shuichi , McGinnis Brian P. , Tian Minquan , Wada Tatsuo , Sasabc Hiroyuki 
Published: April 2011

ABSTRACTWe report the synthesis, and optical characterization of the planar binuclcar phthalocyanines metal free (-1)( H2Pc)2(t-bu)6 and (-l)(VOPc)2(t-bu)6. Several of their optical properties, including linear absorption, concentration dependence, electroabsorption, and transient optical response were measured.
Magnetic Properties Of Tdae-C60: Remanence and Relaxation
Authors: Tokumoto M. , Song Y. S. , Tanaka K. , Sato T. , Yamabe T. 
Published: April 2011

ABSTRACTPrecise measurements of low-field magnetization of TDAE-C60 (TDAE; tetrakis(dimethylamino)ethylene) by SQUID magnetometer revealed a clear “remanence” or “irreversibility”, i.e. difference in the temperature dependence between zero-field cooled (ZFC) and field cooled (FC) conditions below the freezing temperature Tf around 10 K. Also, an extremely slow relaxation phenomena of magnetization was observed. These “glassy” characteristics are reminiscent of a “spin-glass” with Tf at about 10 K as the nature of the magnetic ground state of TDAE-C60.
Electrochromic and Redox Electroactive Polymers Based on Ethylenedioxythiophene Derivatives
Authors: Reynolds John R. , Sankaran Balasubramanian , sotzing Gregory A. , Irvin David J. , Irvin Jennifer A. , Reddinger Jerry L. , Sapp Shawn A. 
Published: April 2011

ABSTRACTA family of electrically conductive polymers based on 3,4-ethylenedioxythiophene (EDOT) and its derivatives will be discussed as electrochromic and redox electroactive materials. Poly(alkylethylenedioxythiophenes), derivatized with octyl and tetradecyl pendant chains, exhibit significantly faster redox switching characteristics than the unsubstituted parent polymer. Bis(2-(3,4-ethylenedioxy)thienyl)arylene (BEDOT-Ar) and vinylene monomers electropolymerize at low potentials avoiding degradative side reactions. We outline the properties of EDOT polymers which exhibit low band gaps allowing for the formation of conductive complexes with a high degree of visible light transmission and show their electrochromic properties. The BEDOT-vinylene polymer, for example, has a band gap of 1.4 eV. A relatively high degree of electrochromic contrast is found at 600 nm as the polymers switch between insulating deep purple absorptive and conductive light blue states. Solid-state dual polymer electrochromic devices have been constructed using a combination of complementary anodically and cathodically coloring polymers based on the EDOT core.
Characterization of the Viscoelastic Behavior of Polyaniline Solutions for Fiber Spinning
Authors: Chacko A. P. , Hardaker S. S. , Huang B. , Gregory R. V. 
Published: April 2011

ABSTRACTSolutions of emeraldine base(EB) in DMPU have been successfully spun into fibers and characterized according to their morphology, mechanical and electrical properties. This study presents results for as-spun (undrawn) fibers. The viscoelastic behavior of EB spin solutions have been investigated with dynamic measurements of the complex moduli, first normal stress coefficient, and complex viscosity. A knowledge of the viscoelastic behavior of emeraldine base solutions is crucial for effective processing into fibers and films.
The Molecular Conformation of Non-Doped Polyaniline and its Effect on the Properties of Doped Polyaniline
Authors: Zheng W. , Min Y. , Lee S-J. , Macdiarmid A. G. , Angelopoulos M. , Liao Y-H. , Epstein A. J. 
Published: April 2011

ABSTRACTWhen thin films of polyaniline (emeraldine base, EB) are deposited on glass substrates from aqueous solutions of polymerizing aniline (“in-situ” EB-I film), they exhibit a Vis/UV spectrum in which the exciton peak has an absorption maximum at ∼600 nm; exposure to NMP vapor results in a shift of this peak to ∼650 nm (EB-II film). Doping of EBI film by aq. HCl gives the characteristic Vis/UV spectrum of “tight coil” doped polyaniline with a localized polaron peak at ∼820 nm. Treatment of EB-II film with HCl in a similar manner gives the characteristic spectrum of “expanded coil” doped polyaniline in which the ∼820 nm peak has disappeared and is replaced by a free carrier tail. It is concluded that EB-I and EB-II exist in “tight coil” and “expanded coil” molecular conformations respectively which do not change on doping in aqueous HCl.
White and Unsaturated Color Organic Light Emitting Diodes
Authors: Dodabalapur A. , Strukelj M. , Jordan R. H. , Rothberg L. J. , Miller T. M. 
Published: April 2011

ABSTRACTWe describe the principles of operation and device characteristics of novel organic light emitting diodes in which the emission originates in a number of optically active layers. The effective emission color can be controlled by adjusting the thicknesses of the individual layers, and in this manner white and other unsaturated color LEDs with external quantum efficiency > 0.5% have been fabricated. The maximum luminance that has been achieved is ∼4,700 Cd/m2.