bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Atomistic Study of the Nickel-Alumina Interfacial Reactions
Authors: Zhong Q. , Ohuchi F. S. 
Published: March 2011

AbstractThe initial stage of formation of the Ni/A12O3 interface under different conditions was studied by various surface science techniques. Nickel was deposited in situ in a UHV system onto the basal plane of a sapphire substrate at various temperatures and oxygen partial pressures. The interfacial reaction processes were simultaneously monitored by XPS. When Ni was deposited at elevated temperatures and in the presence of sufficient oxygen, the NiAl204 spinel was formed epitaxially on the Al2O3 substrate, as confirmed by LEED. While under UHV conditions (<4×10−11 torr) and at elevated temperatures (<800°C), the Al2O3 was partially reduced by Ni, and the evidence of Ni-Al intermetallic alloy formation was observed. Further efforts include the construction of a UHV system capable of preparing interfaces suitable for interfacial structure and adhesion studies.
Interfacial Reactions in the Al/Si3N4/Si and Au/Si3N4/Si Systems
Authors: Edelman F. , Gutmanas E. , Brener R. 
Published: March 2011

AbstractThe interface chemistry and structure of thin Al and Au films deposited on Si3N4 have been studied. In the case of Al/Si3N4 system, an interfacial AIN like layer was observed in the as-deposited state. The thickness of this layer was found to increase with increasing the temperature up to 600°C. This thin AlN layer acts as a diffusion barrier which prevents Al to diffuse into Si3N4 Furthermore, Si released in the reaction between Al and Si3N4 appears to crystallize into small islands dispersed in the interfacial region. In contrast to Al, no reaction between Au and Si3N4 was observed in the as-deposited state. However, after heat treatment at temperatures higher than 400°C gold silicides (Au5Si2,Au2Si,Au3Si) with a very thin Si layer accumulated on the Au surface were observed.
Electrical and Material Characterization of the Stability of ALGaAs and GaAs Planar Doped Structures
Authors: Sadwick Larry P. , Streit Dwight C. 
Published: March 2011

AbstractIn this work we have studied the effects of silicon planar doping on the electrical and optical properties of GaAs, and the effects of rapid thermal annealing on AIGaAs planar-doped structures. MBE-grown GaAs epilayers with multiple planar-doped layers displayed a 1.2 eV photoluminescence peak, presumably due to gallium vacancy - donor complexes, for samples with nominal silicon sheet densities much greater than measured charge densities. The Hall mobilities of these samples were also reduced compared to both uniformly-doped and planar-doped structures whose silicon areal densities were more nearly equal to measured sheet charge densities, although X-Ray rocking curves were nearly identical in all cases. Planar-doped AIGaAs Schottky diodes had nearly ideal electrical characteristics. Rapid thermal annealing of the planar-doped structures before fabrication increased the diode ideality factor from n=1.06 to n=1.60, seriously degraded the saturation current and breakdown voltage, and increased the doping profile FWHM from 60Å to 170Å.
Photoluminescence Studies of Impurities and Defects in Mercuric Iodide
Authors: Bao X.J. , Schlesinger T.E. , James R.B. , Cheng A.Y. , Ortale C. 
Published: March 2011

AbstractWe have studied the effects of chemical etching in potassium iodide(KI) aqueous solution, vacuum exposure and bulk heating on the photoluminescence(PL) spectra of mercuric i0dide(HgI2). Different contact materials deposited onto HgI2 were also investigated, such as Pd, Cu, Al, Ni, Sn, In, Ag and Ta. These processing steps and the choice of a suitable electrode material are very important in the manufacturing of high-quality mercuric iodide nuclear detectors. Comparisons are made between the front surface photoluminescence and transmission photoluminescence spectra.
Electrical and Photoluminescence Properties of Mg+ and C+ Implanted Acceptors in InP.
Authors: Beye A.C. , Yamada A. , Shimizu A. , Shibata H. , Tanoue H. , Mayer K.M. , Sugiyama H. , Kamijoh K. , Oda T. , Arriga O. , Akiyama I. , Kutsuwada N. , Matsumori T. , Uekusa S. , Makita Y. 
Published: March 2011

AbstractImplantation of Mg+ and C+ ions is carried out in bulk InP substrates using single or several energies up to 400 keV. The net carrier concentration profile at 300K is measured by capacitance-voltage (C-V) method. The ground and excited states binding energies of Mg and C acceptors are determined by low-temperature selective excitation of photoluminescence (PL). Additional sharp exciton-Iike emissions are detected after annealing of the samples. Their intensity is found to decrease with increasing Mg+ or C+ dose. Annealing-induced activation and/or formation of complex defect are the likely candidate mechanisms for the involved defect.
Optically Detected Magnetic Resonance of Sulfur Doped Gallium Phosphide
Authors: Brower K. L. 
Published: March 2011

AbstractAn isotropic optically detected magnetic resonance (ODMR) having a Lorentzian lineshape at g - 2.050 ± 0.003 and linewidth (FWHM) of 67.3 mT is observed in GaP doped with 6 - 9 × 1017 S/cm3. The ODMR at g - 2.050 is believed to arise from free electrons (or holes) in the conduction (valence) band. This ODMR is completely quenched due to non-radiative recombination in the vicinity of g - 1.99.
Infrared Absorption Study of Zinc-Doped Silicon.
Authors: Merk E. , Heyman J. , Haller E. E. 
Published: March 2011

AbstractWe report high resolution infrared absorption spectra associated with the deep zinc acceptor in silicon. The optical transitions between ground and bound excited “p-like” states of the neutral helium-like double acceptor Zn0 center have been observed for the first time. The absorption cross section for the hole transition is found to be very small, of the order of 10-17 cm2. Energy spacings of the P3/2 Rydberg series are very similar to the spacings of the group-III acceptors, suggesting that, in spite of the large ground state binding energy, effective mass approximation still applies to the bound excited states. This represents one more case where the strong central cell potential does not significantly disturb the neutral helium-like bound excited states. Similar observations have been made for the less deep neutral double acceptor Be, and for the chalcogens donors S, Se and Te.The optical ionization energy of Zn0/- has been determined to be 2575 cm-1 (319 meV).Two additional sets of absorption lines related to zinc have been observed at 2130 cm-1 and 2758 cm-1. Their origin will be discussed.
Correlation of the 0.8 eV Emission Band with the EL6 Center in GaAs
Authors: Alaya S. , Zaidi M. A. , Marrakchi G. , Maaref H. , Von Bardeleben H. J. , Bourgoin J. C. 
Published: March 2011

AbstractCombined photoluminescence and DLTS investigations of semi-insulating and n-type GaAs before and after a 15min, 850°C heat treatment under AsH3 reveal that the treatment which anneals the EL6 center leads also to a disappearence of the O.8eV PL band. The suggested correlation between EL6 and the O.8eV PL is confirmed by the determination of the electron capture barrier of EL6 and the Franck-Condon shift deduced from the temperature dependence of the PL band leading to a consistant Configuration Coordinate diagram of this defect.
The Electronic Structure of the “0.15 eV” Cu Acceptor Level in GaAs
Authors: Janzén E. , Linnarsson M. , Monemar B. , Kleverman M. 
Published: March 2011

AbstractCu diffused GaAs samples have been investigated using different kinds of FΠR techniques and photoluminescence. The results suggest that tne “0.15 eV” level originates from the ioruzation of a neutral, nearly substitutional Cu acceptor at a Ga site. Furthermore, the results indicate a distortion in the [100] direction. The ground state binding energy obtained from the effective-mass-like excited states is 157.8 meV at 6K.
The Deep 0.11eV Manganese Acceptor Level in GaAs
Authors: Kleverman M. , Janzén E. , Linnarsson M. , Monemar B. 
Published: March 2011

AbstractThe 0.11 eV Mn acceptor has been investigated using different kinds of FΠR techniques, Zeeman spectroscopy, and photoluminescence. The results clearly fits into the Зd5+ shallow hole model for Mn° and show that the 0.11 eV level originates from the io-nization of a neutral, substitutional Mn acceptor at a Ga-site. The ground state binding energy obtained from the effective-mass like excited states is 112.4 meV.
Optical Properties of Novel Vibronic Bands in Electron-Irradiated Tin Doped Silicon
Authors: Svensson J. H. , Monemar B. , Svensson B. G. 
Published: March 2011

AbstractThe optical absorption of two new electronic transitions in silicon doped with tin has been investigated. At low temperatures two no-phonon lines are observed at 2755.3 and 4112.2 cm-1, each with strong coupling to a single quasi-localized vibration in the excited electronic state. These vibrations have quantum energies of 69.6 and 70.2 cm-1, respectively. At higher temperatures coupling to thermally excited vibrational states in the ground electronic states is observed for both lines. The transition with the no-phonon line at 4112.2 cm-1 has been studied in detail and is found to be well described using the adiabatic and Condon approximations. The optical properties of the two transitions are found to be quite similar. Moreover the relative intensities of the two lines are found to be dependent on the optical excitation conditions.
A New Metastable Defect in Silicon, Optical Properties and an Investigation of the Mechanism Causing the Configurational Change
Authors: Svensson J. H. , Monemar B. 
Published: March 2011

AbstractA new optical transition with a no-phonon energy of 0.615 eV discovered in electron-irradiated silicon grown by the Czochralski technique is investigated, revealing metastable properties of the related defect. The investigation is focused on the optical properties of the transition and its associated structure and on the mechanism governing the change of defect configuration. The transformation of the defect to the metastable state is suggested to be induced by excitonic Auger recombination. A pseudo-donor model is presented as an explanation of the optical spectrum.
Uniaxial Stress and Zeeman Measurements on the 943 meV Luminescence Band in Silicon
Authors: Carmo M.C. , Mcguigan K.G. , Henry M.O. , Davies G. , Lightowlers E.C. 
Published: March 2011

AbstractThe photoluminescence from silicon lightly doped with copper and rapidly quenched from ~ 1100° C is dominated by a vibronic band with zero--phonon lines (ZPL) in the region of 943 meV. We have studied the effect of external fields on the electronic properties of this band and the results are consistent with the luminescence occurring at a defect with Td symmetry. The Zeeman measurements indicate that the luminescence is due to the recombination of excitons in J = 1, J = 2 states with the normal ordering of these levels reversed. This reversal is explained by the different response of these states to hydrostatic strains, and it is also argued that strain at the defect provides the binding potential for the exciton.
Defect-Formation Dependence on Group V-Dopant Atoms in Electron-Irradiated Silicon
Authors: Awadelkarim O.O. , Henry A. , Monemar B. , Lindström J.L. 
Published: March 2011

AbstractThe defect states introduced in P-, As- and Sb-doped silicon upon room-temperature electron-irradiation are studied by deep-level transient spectroscopy (DLTS). Evidence is provided for the involvement of the P-atom and the vacancy in the defect complex giving rise to the prominent electron trap commonly observed at ≈ EC-0.4 eV (EC being the edge of the conduction band). This electron trap together with another at EC-0.30 eV, apparently phosphorus related, exhibit configurationally metastable behaviour. Other electron traps observed at EC-0.27 eV and Ec-0.51 eV in Sb-doped material and EC-0.34 eV in As-doped material are attributed to complexes involving Sb and As atoms, respectively.
Hydrogen in Crystalline and Amorphous Silicon
Authors: Chiarotti Guido L. , Buda F. , Car R. , Parrinello M. 
Published: March 2011

AbstractWe investigate static and dynamic properties of hydrogen in crystalline and amorphous silicon by means of ab initio molecular dynamics simulations. In the crystalline case we focus mainly on the diffusion process of an isolated positively charged hydrogen impurity at high temperature. In the amorphous case we analyze the local order and the dynamical properties corresponding to an atomic hydrogen concentration of ~ 11%, typical of a device quality material. In both crystalline and amorphous cases, our results are in good agreement with available experimental data and give unique insight into the microscopic details of hydrogen incorporation in silicon.
Dissociation Kinetics of Shallow-Acceptor-Hydrogen Pairs in Silicon
Authors: Zundel T. , Weber J. 
Published: March 2011

AbstractAnnealing of hydrogenated p-type silicon with a reverse bias applied to a Schottky diode allows us to precisely determine the dissociation frequency vA of shallow acceptor-hydrogen pairs (AH with A = B, Al, Ga, and In). The temperature dependent values of vA satisfy the relation vA = voAexp (-EA/kT), with voB = 2.8 . 1014 s-1, voAl = 3.1 . 1013 s-1, VoGa = 6.9 . 1013 s-1, and voIn = 8.4 · 1013 s-1. The dissociation energies EA depend only weakly on the acceptors: EB = (1.28±0.03)eV, EAl = (1.44±0.02) eV, EGa = (1.40±0.03) eV, and EIn = (1.42±0.05) eV. The dissociation frequency of BH pairs shifts to a lower value when H is replaced by the deuterium isotope.
Passivation of Zn-Acceptors in InGaAs During Rie with CHF3/H2 and CH4/H2
Authors: Möhrle Martin 
Published: March 2011

AbstractReactive ion etching of highly Zn-doped InGaAs with hydrogen-containing gases such as CHF3/H2, CH4/H2 and CH4/He leads to a drastical reduction of the concentration of electrically active acceptors in a near-surface layer. Ti/Pt/Au contacts applied on as-treated p++-InGaAs layers show non-ohmic I/V-characteristics due to this passivation effect. Annealing at moderate temperatures (330°C, 20 minutes) was found to restore full electrical activity.
Surface Protection during Plasma Hydrogenation for Acceptor Passivation in InP
Authors: Lopata J. , Dautremont-Smith W. C. , Pearton S. J. , Lee J. W. , Ha N. T. , Luftman H. S. 
Published: March 2011

AbstractVarious dielectric and metallic films were examined as H-permeable surface protection layers on InP during H2 or D2 plasma exposure for passivation of acceptors in the InP. Plasma deposited SiNx, SiO2, and a-Si(H) films ranging in thickness from 85 to 225 Å were used to protect p-InP during D2 plasma exposure at 250°C. Optimum protective layer thicknesses were determined by a trade-off between the effectiveness of the layer to prevent P loss from the wafer surface and the ability to diffuse atomic H or D at a rate greater than or equal to that in the underlying InP. SIMS and capacitance-voltage depth profiling were used to determine the extent of D in-diffusion and acceptor passivation respectively. Sputter deposited W and e-beam evaporated Ti films ~100 Å thick were also evaluated. The W coated sample yielded similar results to those with dielectric films in that acceptors in p-InP were passivated to a similar depth for the same plasma exposure. The 100 Å Ti film, however, did not allow the D to diffuse into the InP substrate. It is surmised that the Ti film trapped the D, thus preventing diffusion into the substrate.
Determination of Diffusion Parameters for Arsenic
Authors: Heinrich Michael , Budil Matthias , Pötzl Hans W. 
Published: March 2011

AbstractThis paper deals with an analysis of the oxynitridation and direct nitridation experiments of Fahey et al.(1984[1]). The inconsistencies in the evaluation of the fiactional component of diffusion for aisenic are discussed. Using a recently developed diffusion model an explanation for the diffusion data for arsenic is given. The standard equation for analyzing diffusion under nonequilibrium conditions is shown to lead to erroneous results. A consistent treatment must account for the concentrations of arsenic, point defects and arsenic point defect pairs. Pair formation kinetics must be included. Values are presented for the diffusion constants DIAs, DVAS, and the reaction constants kIAs, kVAs depending on the fractional interstitial component of diffusion .
Measurements of Enhanced Oxygen Diffusion in Silicon During Thermal Donor Formation: New Evidence for Possible Mechanisms
Authors: Brown A.R. , Murray R. , Newman R.C. , Tucker J.H. 
Published: March 2011

AbstractCzochralski silicon has been heated in a H-plasma at temperatures in the range 300-450°C, and compared with furnace annealed material. Plasma treatments produce enhanced rates of oxygen diffusion jumps, loss of oxygen from solution and formation of thermal donor centres. The available evidence indicates that atomic hydrogen catalyses the enhancements via the oxygen diffusion rate. Donor concentrations greater than 1017cm-3 have been observed in samples heated in a plasma at 350°C. Doubts have been raised about dimer formation being the primary mechanism for oxygen loss in furnace anneals at 350°C, but invoking enhanced diffusion leads to a conflict with stress dichroism data.
Anomalous Transient Tail Diffusion of Boron in Silicon: Kinetic Modeling of Diffusion and Cluster Formation
Authors: Cowern N.E.B. , Jos H.F.F. , Janssen K.T.F. , Wachters A.J.H. 
Published: March 2011

AbstractA kinetic modeling approach is used together with experimental studies to gain insight into the processes taking place during anomalous transient diffusion. A physical process analogous to B clustering is found to play an important role, even at B concentrations well below the solid solubility limit.
Failure of the “Kick-Out” Model for the Diffusion of Au into Si when Tested by Monte Carlo Simulation
Authors: Schmid U. , Van Vechtent J. A. , Myers N. C. , Koch U. 
Published: March 2011

AbstractWe have performed large scale computer simulations on the controversial issue of Au diffusion into Si at T = 1095° C. Using a Monte Carlo algorithm and a conveniently parametrized set of parameters, our computer program is capable of working out the macroscopic consequences of a variety of models, i.e. atom level assumptions, in an unbiased way and without the approximations introduced in analytic calculations.When applied to the “kick-out” hypothesis, our results are dramatically at odds with the properties claimed by its proponents. Neither the profile of the Au substitutionals, nor the Au-interstitial profiles are in agreement with the analytically obtained results. The discrepancy becomes most pronounced when comparing the variation with time of the Au concentration in the center of the sample, which we find to be linear at all times, in contrast to the alleged t1/2 behavior. Moreover, the Au profile of a one-sided diffusion never becomes U-shaped, as experimentally observed.
Diffusion of Au in Amorphous Si Measured by the Artificial Multilayer Technique
Authors: Nygren E. , Park B. , Goldman L.M. , Wu D.T. , Wagner A.V. , Spaepen F. 
Published: March 2011

AbstractThe diffusivity of Au in amorphous Si (a-Si) has been determined in the temperature range 200-260°C using and Ar-ion sputter deposited artificial multilayered films of a-Si and a-Si(0.7at%Au) with repeat lengths between 44 and 48 Å. Diffusion on lengths scales of the order of interatomic spacings have been investigated. The Au diffusivity exhibits an Arrhenius temperature dependence with an activation enthalpy of 1.2eV and shows good agreement with extrapolations of higher temperature Au diffusion data obtained by Rutherford backscattering spectrometry (RBS) in ion-implanted, CVD, and sputter deposited a-Si. The measured Au diffusivity also shows a significant time dependence.
Photoluminescence Excitation Spectroscopy of MOCVD-Grown: GaAs:V
Authors: Kao Y.J. , Haegel N.M. , Hobson W.S. 
Published: March 2011

AbstractPhotoluminescence excitation spectra have been obtained at 4.2 K for the characteristic V3+ intra-center emission (0.65 – 0.75 eV) of MOCVD-grown GaAs:V. Oscillatory structure of the PLE spectrum with above-band-edge excitation has been observed in GaAs:V for the first time. The oscillatory period is found to be 41.3 ± 0.5 meV, corresponding to , and is due to energy relaxation of conduction band electrons through LO phonon emission. Our results suggest capture by a shallow donor as an intermediate step in the luminescence from the V center.
Atomic Layer Epitaxy of GaAs on Ge Substrates
Authors: Ramdani J. , Mcdermott B.T. , Bedair S.M. 
Published: March 2011

AbstractWe report on the low temperature growth of GaAs on Ge substrates using Atomic Layer Epitaxy. Low temperature deposition has resulted in substantial reduction of the outdiffusion of Ge into the GaAs epilayer as being indicated from SIMS. The I-V characteristics of the GaAs/Ge heterojunction were thyristor like or near abrupt depending on the growth temperature. We also report on the use of the Atomic Layer Epitaxy self-limiting adsorption process of TMGa to control the diffusion of Ga into Ge substrates at the monolayer level.
An Examination of the Mechanisms of Si Diffusion in GaAs
Authors: Yu Shaofeng , Gosele Ulrich M. , Tan Teh Y. 
Published: March 2011

AbstractAn examination of the three available quantitative models of Si diffusion in GaAs has led to the conclusion that the Fermi-level effect mechanism plays the most essential role. In some experimental results a point defect concentration transient is involved which should be incoorporated in future models.
Mechanism for the Diffusion of Zinc in Gallium Arsenide
Authors: KAHEN K. B. 
Published: March 2011

AbstractThe anomalous shape of the Zn diffusion profile in GaAs has been quantitatively explained. The interchange between interstitial Zn and substitutional Zn is assumed to occur via the Ga vacancies. These vacancies are proposed to be either neutral or singly ionized, depending on the position of the Fermi level. In addition, two physical phenomena are proposed. Substitutional Zn thermally generates interstitial Zn-Ga vacancy pairs and there is pairing between the donor, interstitial Zn and the acceptor, substitutional Zn. This pairing leads to the interstitial Zn diffusivity being a decreasing function of the substitutional Zn concentration. The model is found to be in good agreement with the experimental data.
Diffusion of Ion-Implanted Tin in Gallium Arsenide
Authors: Allen E.L. , Deal M.D. , Plummer J.D. 
Published: March 2011

AbstractThe diffusion of ion-implanted tin in gallium arsenide was investigated as a function of temperature, dose and background doping. The chemical depth profiles were determined using SIMS and the carrier profiles were determined by CV Etch Profiling. The data was fit using a numerical process simulator, SUPREM 3.5. Sn diffusivity was found to depend on the square of the electron concentration. Sn and Ge were found to have relatively high diffusivities when implanted, while Si diffused very little.
Impurity-Induced Layer Disordering: Current Understanding and Areas for Future Investigation
Authors: Guido L.J. , Holonyak Nick 
Published: March 2011

AbstractThe purpose of this work is to give an overview of the current phenomenological understanding of impurity-induced layer disordering (IILD). First, we identify key experimental findings such as the influence of the crystal surface-ambient interaction, the Fermi-level effect, and the impurity concentration on Al-Ga interdiffusion. Second, we review the strengths and weaknesses of existing IILD models in consideration of the above mentioned experimental data. Finally, we discuss the pitfalls involved in generalizing the results of individual Al-Ga interdiffusion experiments in order to explain a broader collection of IILD data.