bluuebunny/crossref_metadata_2025_split huggingface dataset:
Atomic Structure of 66° [110] Asymmetric Tilt Grain Boundary in Aluminum
Authors: Shamsuzzoha M. , Deymier P. A. , Smith David J. 
Published: April 2011

ABSTRACTA 66° [110] asymmetric tilt grain boundary in Al prepared by cold rolling and annealing has been studied by high-resolution electron microscopy. Due to a 4.5° deviation from the perfect Σ3 misorientation, the boundary is heavily faceted with straight segments running parallel to (111) and (112) planes. All atomic sites across the (111) facets appear to be coincident with the (111) planes at an angle of 66°. The line defects which accommodate the deviation from the perfect twin orientation result in grain boundary stepping. The observed structural features can be described in terms of secondary grain boundary dislocations with Burgers vectors of the type ⅓<111>, and ⅙<112> as well as their interactions.
Kinetic Investigations of the Initial Oxidation Stage of Copper by In-Situ UHV-TEM
Authors: Yang J. C. , Yeadon M. , Kolasa B. , Olynick D. , Gibson J. M. 
Published: April 2011

ABSTRACTWe have examined the nucleation and growth of copper oxides formed by in-situ oxidation of copper thin films inside a modified transmission electron microscope (TEM). Based on this data, we have developed a semi-quantitative model of the initial oxidation stage where the dominant mechanism for transport, nucleation and growth of oxide islands is oxygen diffusion on the surface. The copper oxide can be desorbed by annealing and introducing methanol vapor into the chamber. The clean copper film can be oxidized by introducing oxygen gas. Both the desorption and oxidation processes were observed by planar TEM techniques. The copper film was oxidized in-situ at a partial pressure of 5×104torr. Cu2O islands, which formed epitaxially to the copper film, nucleated and grew into the copper film.
Grain Boundaries In Diamond Films On Si(001)
Authors: Wittorf D. , Jia C. L. , Jäger W. , Grushko B. , Urban K. , Jiang X. , Paul M. , Klages C.-P. 
Published: April 2011

ABSTRACTGrain boundaries in [001]-oriented diamond films deposited on Si(001) by microwave-assisted chemical vapor deposition have been investigated in plan-view and cross-section samples using high-resolution electron microscopy. The poly-crystalline diamond films used in this study had large fractions of [001]-oriented grains with typical lateral dimensions of 2 μm at film thicknesses beyond 10 μm. Grains with growth orientations near (001) exhibit generally small-angle orientation deviations between their crystal lattices. Small-angle grain boundaries of symmetric and asymmetric geometry with misorientation angles below 15° are investigated in both [110]- and [001]-directions. It is found that the structures of such small-angle grain boundaries can be described by a dislocation model. These grain boundaries are on average parallel to the {110}-plane and contain in many cases micro-facets parallel to {lll}-planes. Large-angle grain boundaries with tilt angles up to 40° are also observed in interconnected films of smaller thickness. In all cases structural units with large open volumes and additional second phases are not found at the grain boundaries.
Metal-ZnO Interfaces Studied by High Resolution Transmission Electron Microscopy
Authors: De Hosson J.Th.M. , Vellinga W. P. , Groen H. B. , Kooi B. J. 
Published: April 2011

ABSTRACTThis paper reports on investigations of Ag-ZnO and Cu-ZnO interfaces, produced by internal oxidation. ZnO precipitates with the wurtzite structure were found showing mainly one orientation relationship (OR) with the matrix. However, closely related ORs were found, rotated by small angles from that orientation relation. The atomic structure of several interfaces surrounding these precipitates was studied and compared using high resolution transmission electron microscopy. This paper focuses on interfaces between low index facets of ZnO and vicinal planes of Ag. These interfaces clearly show relaxations. An interpretation of these relaxations in terms of dissociation of partial dislocations at the interface is put forward.
STM Study of Initial Growth of Titanium Silicide on Si(III)
Authors: Kuriyama H. , Ohara S. , Ezoe K. , Yamamoto T. , Tatsukawa S. , Umekawa M. , Matsumoto S. 
Published: April 2011

ABSTRACTThe nucleation and initial growth of titanium suicide on Si(111)7×7 surface has been studied using the scanning tunneling microscopy(STM) in ultrahigh vacuum. At room temperature Ti atoms react with Si atoms and preferentially adsorb on faulted half of the 7×7 surface. By annealing at 600°C, islandlike structures(amorphous titanium suicide) and striplike structures(crystalline titanium suicide) are formed. Annealing at 700°C drives the growth of striplike structures from islandlike structures. The striplike structures grow parallel to specific directions on the 7×7 surface.
Native Defects and their Interactions with Impurities in Silicon
Authors: Watkins G. D. 
Published: April 2011

ABSTRACTA review is given of what has been learned from EPR studies over the last ∼35 years concerning vacancies and interstitials in silicon. Lattice vacancies are well understood, their diffusional migration energies determined vs charge state and electronic excitation, and their interactions with most of the common impurities established. The isolated interstitial has not been observed by EPR but a great deal has been learned concerning it from studies of its interactions with impurities, and more recently from theory. The properties of these two intrinsic defects and their progeny will be analyzed to help clarify their role in both the normal thermally activated diffusion processes and the transient-enhanced ones, which are of particular current concern.
Fully Atomistic Analysis of Diffuse X-Ray Scattering Spectra of Silicon Defects
Authors: Nordlund K. , Partyka P. , Averback R. S. 
Published: April 2011

ABSTRACTDiffuse X-ray scattering is a useful method for studying defects in silicon and metals. Although the traditional approaches of analyzing experimental diffuse X-ray scattering data have given much information about the size of defects and defect clusters, they are not very well suited for determining the atomic configuration. We present a fully atomistic computational method to calculate the diffuse X-ray scattering line profile of an arbitrary atomic configuration, and compare line profiles of point defects and Frenkel pair configurations with experiment.
Effect of Implant Energy on Silicon Defect Evolution
Authors: Desroches J. , Krishnamoorthy V. , Jones K. S. , Jasper C. 
Published: April 2011

ABSTRACTRecent studies on the relationship between defect evolution and transient enhanced diffusion (TED) have lead to the discovery that, for sub-amorphous Si+ implants, atoms released by extended defects (i.e. {311}'s) are a primary source of interstitials for TED. In this paper, the effect of implant energy on the interstitials stored in {311} defects is reported. Silicon wafers were implanted with Si+ at fluences of 1×1014/cm2 and 2×1014/cm2 and energies of 30, 50 and 100 keV. Rapid thermal anneals (RTA) and furnace anneals were performed at times ranging from a few minutes to several hours, at temperatures of 700°, 750° and 800°C. Cross-sectional and plan-view TEM was used to obtain microstructural information. The extended defects observed upon annealing consisted of both {311} defects and dislocation loops. It was found that the ratio of the interstitials bound by extended defects and the implant dose was 0.3. Changing the implant energy did not change the total number of interstitials trapped in both types of defects combined. There was a noticeable variation in the type of defect that dominated each implant regime, despite the constant value of the trapped interstitial to dose ratio. For an RTA of 5 min. at 750°C, the ratio of {311} “rod-like” defects to dislocation loops in the 2×1014/cm2 sample unexpectedly increased as the energy increased from 30 to 50 keV.Longer furnace anneals were employed to determine the activation energy of {311} dissolution. Our data suggests a slightly higher activation energy for {311} dissolution of approximately 4.2 eV versus the previously reported 3.6 eV, however, this difference may be within experimental error.
Defects and Diffusion issues for the Manufacturing of Semiconductors in the 21st Century
Authors: Plummer J. D. 
Published: April 2011

ABSTRACTWithin the past decade, process simulation has become an essential part of new technology development in the silicon IC industry. The use of TCAD (technology computer aided design) tools has been driven by the enormous cost of purely experimental approaches to technology development. Yet the power of these tools and their predictive capability are still greatly limited by the models they use. TCAD models for doping processes are universally based today on point defects. These models have evolved considerably in the past decade to incorporate additional understanding. The state-of-the-art today includes concentration dependent diffusion through Fermi level effects on defect concentrations, full coupling between defects and dopants which allows prediction of non-local diffusion effects, basic models for the effects of ion implantation damage (the +1 model), surface and interface effects (through effective recombination velocities and segregation), and full 2D and 3D simulations.As devices continue to shrink, better models will certainly be required. Challenges for the future include more detailed information about damage resulting from ion implantation, better understanding of point defect properties (equilibrium populations, diffusivities, transient response to temperatures changes), better models for point defect behavior at interfaces, and finally, development of accurate methods to actually measure 2D and 3D dopant profiles. This paper will attempt to describe where we are and where we need to be in the future.
Enhanced Diffusion of Dopants in Vacancy Supersaturation Produced by MeV Implantation
Authors: Venezia V. C. , Haynes T. E. , Agarwal A. , Gossmann H. -J. , Eaglesham D. J. 
Published: April 2011

ABSTRACTThe diffusion of Sb and B markers has been studied in vacancy supersaturations produced by MeV Si implantation in float zone (FZ) silicon and bonded etch-back silicon-on-insulator (BESOI) substrates. MeV Si implantation produces a vacancy supersaturated near-surface region and an interstitial-rich region at the projected ion range. Transient enhanced diffusion (TED) of Sb in the near surface layer was observed as a result of a 2 MeV Si+, 1×1016/cm2, implant. A 4× larger TED of Sb was observed in BESOI than in FZ silicon, demonstrating that the vacancy supersaturation persists longer in BESOI than in FZ. B markers in samples with MeV Si implant showed a factor of 10× smaller diffusion relative to markers without the MeV Si+ implant. This data demonstrates that a 2 MeV Si+ implant injects vacancies into the near surface region.
Influence of dynamic annealing on the depth distribution of germanium implanted in (100) silicon at elevated temperatures
Authors: Nejim A , Jeynes C , Webb R P , Cowern Neb , Patel C J 
Published: April 2011

Abstract(100) silicon wafers were implanted at elevated temperatures up to 600°C with l×lO15-5×1015 Ge+/cm2 using 120 keV. The wafers were tilted by 5–7° and rotated by 5–15°. The implanted germanium profile was monitored as a function of implant temperature using RBS-channelling. Considerable profile broadening was seen together with apparent mass germanium migration away from the surface in samples implanted at 300°C and above. Control implants into hot and cold samples simultaneously rule out excess loss of germanium from the heated wafers. Channelling data indicate that while room temperature implants lead to amorphisation, with hot implants good quality layers are obtained in which the germanium atoms occupy substitutional sites. Hot implants into a sample previously implanted with germanium at room temperature does not lead to any redistribution in the original germanium profile. This result indicates that the apparent enhanced indiffusion of germanium is not a radiation assisted phenomenon and could be explained by a considerable channelling of the implanted germaniumatoms along the <100> direction.
Lattice Sites and Damage Annealing of Implanted Tm and Er IN Si
Authors: Wahl U. , Correia J. G. , De Wachter J. , Langouche G. , Marques J. G. , Moons R. , Vantomme A. ,   ISOLDE collaboration
Published: April 2011

ABSTRACTWe have studied the lattice sites of Er in CZ Si single crystals by using conversion electron emission channeling from the isotope 167mEr (2.27 s) which is the decay product of radioactive Tm 167m(9.25 d). Following 60 keV implantation of 167Tm at a dose of 4×1013 cm−2 and annealing at 600°C, more than 90% of 167mEr is found close to tetrahedral insterstitial(T) sites. The tetra-hedral fraction of 167mEr decreases considerably after 10min annealing at 800°C and above. We attribute this to the onset of diffusion of the parent 167Tm and its trapping at other defects, presumably oxygen atoms or clusters of Tm/Er.
Internal Friction in Ion-Implanted Silicon
Authors: Liu Xiao , Pohl R. O. , Crandall Richard S. , Jones K. M. 
Published: April 2011

ABSTRACTUsing a double-paddle oscillator, we have studied the internal friction of thin Si layers which have been disordered by ion implantation. We have identified the temperature-independent internal friction common to all amorphous solids below 10K, and also a narrow relaxation peak at ∼ 48K. This peak has been shown to be caused by divacancies in the damaged crystalline region underneath the amorphous layer. Thermal, rapid thermal, and laser-flash annealing have been compared. The minimum disorder is left after rapid thermal annealing.
Tem Observations of AG-TI Bilayers After Thermal Aging Treatment in a Reducing Ambient
Authors: Amali Adam I. , Mayer J.W. , Zeng Yuxiao , Zou Y.L. , Alford T.L. , Deng F. , Lau S.S. 
Published: April 2011

ABSTRACTTransmission electron microscopy (TEM) in both cross sectional and plan view is used to study the effect of annealing Ag-Ti bilayers deposited on SiO2/Si substrates in an NH3 ambient. The resulting structure, texture and grain size are investigated. Comparisons are made between films annealed at 400, 500 and 600 °C. Silver films show increasingly strong <111> texture with annealing temperature while exhibiting a bamboo-like grain structure at 600 °C. Considerable grain growth with lateral grain sizes of up to 5 times the thickness of the Ag film is observed at 600 °C. The grains typically extend through the Ag film thickness. The Ti/SiO2 interface uniformity and the absence of voids at the substrate surface are positive indicators of the role of titanium as a good adhesion promoter. At 600 °C, a uniform TiN encapsulation layer is observed on the Ag surface.
Change From Polycrystalline to Amorphous Growth in Sputtered CoZr/Cu Multilayers
Authors: Langer J. , Mattheis R. , Schmidt S. , Senz St. , Hesse D. , Schuhrke Th. , Fischer R. , Zweck J. 
Published: April 2011

ABSTRACTWe present an investigation of structural changes occurring in bilayer stacks with crystalline columnar growth when one of the layers is substituted by layers known to grow amorphous. In Co/Cu multilayers the Co layers were substituted by CoZr layers of varying Zr content and layer thickness. Structural characterisation was performed by transmission electron microscopy (TEM). We show that the amorphisation of the CoZr layers leading to a destruction of the columnar growth depends both on the Zr content and on the thickness of the CoZr layers. Additionally a change to textured growth with a <111> normal to the substrate occurs with increasing Zr content. We explain our observations by a simple picture based on the hard sphere model.
Morphology and Texture of Chemical-Vapour-Deposited TiN Films
Authors: Yoshikawa Noboru , Taniguchi Shoji , Kikuchi Atsushi 
Published: April 2011

ABSTRACTTiN films were obtained by Chemical Vapour Depositon (CVD) under different deposition conditions. Their grain structure, morphology and preferred crystal orientation were investigated. It was observed that well-defined columnar grams developed under conditions of atmospheric thermal CVD, giving rise to strong preferred orientations. In this study, grain structures of CVD-TiN films were classified with respect to the substrate temperature. Films of zone I structure were obtained at 1173K (0.35Tm), and those of zone II were obtained at 1223K (0.38Tm). Crystal shape of the zone II columnar grains was influenced by the partial pressure of TiCl4 (PTiCl4), and the crystal orientation of films was related to the crystal shapes. Columnar grains increased their thickness during deposition process under conditions of low PTiC14 and high temperature (>1250K). The increase rate of grain size had a similar time dependence to that of normal grain growth. The “quadrangular-shaped” and “star-shaped” columnar crystals were formed. They consisted of several crystals and contained twins. Their microstructures were observed in relation to their crystallographic features.
Stress Control in Sputtered Silicon Nitride Films
Authors: Mescher M. J. , Reed M. L. , Schlesinger T. E. 
Published: April 2011

ABSTRACTWe show that stress in sputter-deposited silicon nitride films can be controlled, making either compressive or tensile stress films achievable. These films were deposited via reactive rf magnetron sputtering using an elemental Si target and N2 as a reactive gas in an Ar ambient. Variation of stress as a function of deposition pressure and N2/Ar gas mixture ratio was examined over a wider range of these two parameters than in previous work. More importantly, this parameter space includes conditions which produce near-stoichiometric Si3N4 films over a wide range of deposition pressures. We demonstrated that both low compressive stress and even tensile stress can be achieved at the proper deposition conditions. The film stresses as a function of deposition pressure or N2/Ar gas flow ratio are explained in the context of previously developed peening models.
Heteroepitaxial Growth of Cubic Boron Nitride Single Crystal on Diamond Seed Under High Pressure
Authors: Taniguchi T. , Yamaoka S. 
Published: April 2011

ABSTRACTSingle crystal cubic boron nitride(cBN) was heteroepitaxially grown on a seed crystal of diamond under static high pressure and high temperature of 5.5GPa and 1600–1700°C, respectively, for 10–100 hour. A temperature gradient method was employed for the crystal growth by using lithium boron nitride as a solvent. Initial growth feature of cBN crystal was found on the diamond seed surface after the growing time of 10 minutes. The nucleation sites of the crystals seem to be near the etch pits on the diamond surface which were introduced by the surface dissolution by the solvent for cBN growth. Two types of growth features, island and step growth were typically shown on the surface. It can be seen that grown crystal appearing as a (111) nitrogen face was exhibited with the step growth feature, while the (11n) face exhibited the island growth feature. Considering the growth process under constant P-T growing condition, growth rate of cBN crystal was significantly small as compared to that of diamond.
Practical considerations in Megasonic Wafer
Cleaning
Authors: Hall R. Mark , Jarvis Taura , Parry Thad 
Published: April 2011

ABSTRACTIn this study, critical hardware and process parameters are evaluated for
their effect on performance in megasonic cleaning applications. Experimental
data is presented which shows the impact of transducer design, bath
temperature, process time, SC1 chemistry, and wafer gap spacing on particle
removal and surface roughness. The ability to remove particles smaller than
0.1 um in size is also demonstrated.
A Novel Surface Preparation and Post-Etch Removal Technique for
InGaAs Sidewalls
Authors: Tabatabaei S. A. , Porkolab G. A. , Agarwala S. , Johnson F. G. , Merritt S. A. , King O. , Dagenais M. , Chen Y. J. , Stone D. R. 
Published: April 2011

ABSTRACTThis paper describes in detail a surface preparation, and post-etch removal
technique developed for InGaAs sidewalls. It illustrates the results
demonstrating the effect of sidewall post-etch, surface preparation, and
surface passivation on the performance of high speed InGaAs detectors. Dark
current density for circular diodes with a diameter size varying between 10
and 100 μm was measured at a reverse bias voltage of −5 V. The effectiveness
of various surface preparation techniques was studied by measuring the
immediate improvement in dark current density, as well as its long-term
stability. The benefits of this new technique compared to other techniques
we have investigated include improved device characteristics, long-term
stability, as well as a much less critical process to achieve optimum
surface properties.
Valence Band Discontinuity at and Near The
SiO2/Si(111) Interface
Authors: Nohira Hiroshi , Hattori Takeo 
Published: April 2011

ABSTRACTThe changes in X-ray excited valence band of silicon oxide during
progressive oxidation of Si(111) surface in 1 Torr dry oxygen at 600–850°C
were studied. Following results are obtained: 1) energy level of top of
valence band within 0.9 nm from the SiO2/Si interface is
different from that of bulk silicon oxide by about 0.2 eV, 2) valence band
discontinuity at the interface changes periodically with the interface
structures.
A Model for the Etching of Ti and Tin in SC-1
Solutions
Authors: Verhaverbeke Steven , Parker Jennifer W. 
Published: April 2011

ABSTRACTThe Standard Clean 1 (SC-1), developed by W. Kern and D. Puotinen in 1965
and disclosed in 1970 [1], consists of a mixture of ammonium-hydroxide,
hydrogen-peroxide, and water. (SC-1 is also called the Airfmonium-Hydroxide
Peroxide Mixture or APM). Originally, this chemical mixture was developed
for cleaning silicon wafers and it has proven to be the most efficient
particle removing agent found to date. SC-1 can, however, also be used for
etching. SC-1 will etch the following materials: SiO2,
Si3N4, Si, Ti and TiN. On top of this, SC-1 will
grow an oxide on several materials (i.e., bare silicon).In this paper, a quantitative model for the SC-1 solution is presented. The
etching of Ti and TiN is shown to be fundamentally different from the
etching of SiO2. The mixture of Ammonium-hydroxide and Hydrogen
Peroxide must be optimized differently for Ti and TiN etching than for the
particle removal from Silicon wafers.
The Enhancement of Thermoelectric Power and Scattering of Carriers in Bi2−xSnxTe3 Single Crystals
Authors: Kulbachinskii V.A. , Negishi H. , Sasaki M. , Giman Y. , Inoue M. 
Published: April 2011

AbstractThermoelectric power, electrical resistivity, and Hall effect of p-type Bi2−xSnxTe3 (0<x<0.03) singlecrystals have been measured in the temperature range 4.2–300K. By doping of Sn atoms into the host Bi2Te3 lattice, the enhancement in the thermoelectric power is observed in the intermediate temperature range 30–150 K for x≤0,0075. The activation type behaviour of Hall coefficient and resistivity are found which corresponds to the Sn-induced impurity band located above the second lower valence band.
Thermoelectric Properties of ZnSb Films Grown by MOCVD
Authors: Venkatasubramanian R. , Watko E. , Colpitts T. 
Published: April 2011

AbstractThe thermoelectric properties of ZnSb films grown by metallorganic chemical vapor deposition (MOCVD) are reported. The growth conditions necessary to obtain stoichiometric ZnSb films and the effects of various growth parameters on the electrical conductivity and Seebeck coefficients of the films are described. The as-grown ZnSb films are p-type. It was observed that the thicker ZnSb films offer improved carrier mobilities and lower free-carrier concentration levels. The Seebeck coefficient of ZnSb films was found to rise rapidly at approximately 160°C. The thicker films, due to the lower doping levels, indicate higher Seebeck coefficients between 25 to 200°C. A short annealing of the ZnSb film at temperatures of ˜ 200°C results in reduced free-carrier level. Thermal conductivity measurements of ZnSb films using the 3-ω method are also presented.