bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fluidic Surface-Tension-Directed Self-Assembly of Miniaturized Semiconductor Dies Across Length Scales and 3D Topologies
Authors: Jacobs Heiko , Knuesel Robert J 
Published: August 2010

AbstractThis proceeding discusses recent progress on engineered fluidic surface-tension-directed self-assembly involving liquid solder. The process is applied to the assembly of discrete inorganic semiconductor device components at different length scales producing electrically interconnected devices and systems. Prior results include assembly with unique angular orientation and contact pad registration, parallel packaging, and the programmable assembly of various types of light emitting diodes. Recent progress on the scaling of the minimal die size from 300 to 30 μm is discussed which required the development of a new delivery system to concentrate and effectively introduce the components to solder-based receptors. Specifically, components are pre-oriented at a liquid-air or liquid-liquid interface and transferred onto the solder based receptors using a dynamic contact angle with a dipping process. Recent applications include the tiling of curved and 3D surfaces with single crystal semiconductors including the formation of flexible 3D solar cells.
An Integral Equation based Numerical Solution for Nanoparticles Illuminated with Collimated and Focused Light
Authors: Sendur Kursat 
Published: August 2010

AbstractAn integral equation based numerical solution is developed when the particles are illuminated with collimated and focused incident beams. The solution procedure uses the method of weighted residuals, in which the integral equation is reduced to a matrix equation and then solved for the unknown electric field distribution. In the solution procedure, the effects of the surrounding medium and boundaries are taken into account using a Green’s function formulation. Therefore, there is no additional error due to artificial boundary conditions unlike differential equation based techniques, such as finite difference time domain and finite element method. In this formulation, only the scattering nano-particle is discretized. The results are compared to the analytical Mie series solution for spherical particles, as well as to the finite element method for rectangular metallic particles. The Richards-Wolf vector field equations are combined with the integral equation based formulation to model the interaction of nanoparticles with linearly and radially polarized incident focused beams.
Chemical Nano-tomography of Self-assembled Ge-Si:Si(001) Islands from Quantitative High Resolution Transmission Electron Microscopy
Authors: Montoro Luciano Andrey , Leite Marina , Biggemann Daniel , Peternella Fellipe Grillo , Batenburg Kees Joost , Medeiros-Ribeiro Gilberto , Ramirez Antonio J. 
Published: August 2010

AbstractThe knowledge of composition and strain with high spatial resolution is highly important for the understanding of the chemical and electronic properties of alloyed nanostructures. Several applications require a precise knowledge of both composition and strain, which can only be extracted by self-consistent methodologies. Here, we demonstrate the use of a quantitative high resolution transmission electron microscopy (QHRTEM) technique to obtain two-dimensional (2D) projected chemical maps of epitaxially grown Ge-Si:Si(001) islands, with high spatial resolution, at different crystallographic orientations. By a combination of these data with an iterative simulation, it was possible infer the three-dimensional (3D) chemical arrangement on the strained Ge-Si:Si(001) islands, showing a four-fold chemical distribution which follows the nanocrystal shape/symmetry. This methodology can be applied for a large variety of strained crystalline systems, such as nanowires, epitaxial islands, quantum dots and wells, and partially relaxed heterostructures.
Hybrid Tomography of Nanostructures in the Electron Microscope
Authors: Saghi Zineb , Gnanavel Thirunavukkarasu , xu xiaojing , Möbus Guenter 
Published: August 2010

AbstractA variety of tomographic experiments and modes for electron tomography of nanostructures are introduced, derived from the general concepts of quantitative computed tomography, binarised geometric tomography, including shape-from-silhouette, and spectroscopic chemical mapping. Our emphasis is on working out concepts of combining at least two of these tomography modes in order to share their respective advantages and improve the overall reconstruction quality. In this work, the following three hybrid modes are presented: (i) ADF-STEM tomography and EDX tomography into high-resolution 3D chemical mapping, (ii) geometric tomography and lattice-resolved backprojection into HREM-tomography for convex bodies, and (iii) geometric tomography and e-beam nanosculpting into “tomographic nanofabrication”.
Characterization of Nanostructured Organic-Inorganic Hybrid Materials Using Advanced Solid-State NMR Spectroscopy
Authors: Mao Kanmi , Rapp Jennifer L. , Wiench Jerzy W. , Pruski Marek 
Published: August 2010

AbstractWe demonstrate the applications of several novel techniques in solid-state nuclear magnetic resonance spectroscopy (SSNMR) to the structural studies of mesoporous organic-inorganic hybrid catalytic materials. Most of these latest capabilities of solid-state NMR were made possible by combining fast magic angle spinning (at ≥ 40 kHz) with new multiple RF pulse sequences. Remarkable gains in sensitivity have been achieved in heteronuclear correlation (HETCOR) spectroscopy through the detection of high-λ (1H) rather than low-λ (e.g., 13C, 15N) nuclei. This so-called indirect detection technique can yield through-space 2D 13C-1H HETCOR spectra of surface species under natural abundance within minutes, a result that earlier has been out of reach. The 15N-1H correlation spectra of species bound to a surface can now be acquired, also without isotope enrichment. The first indirectly detected through-bond 2D 13C-1H spectra of solid samples are shown, as well. In the case of 1D and 2D 29Si NMR, the possibility of generating multiple Carr-Purcell-Meiboom-Gill (CPMG) echoes during data acquisition offered time savings by a factor of ten to one hundred. Examples of the studied materials involve mesoporous silica and mixed oxide nanoparticles functionalized with various types of organic groups, where solid-state NMR provides the definitive characterization.
Mechanical Function of a Complex Three-dimensional Suture Joining the Bony Elements in the Shell of the Red-eared Slider Turtle
Authors: Shahar Ron , Kraus Stefanie , Monsonego-Ornan Efrat , Fratzl Peter 
Published: August 2010

AbstractCertain design strategies appear repeatedly in a variety of biological structures. One such motif consists of a soft and pliable interface joining much larger and stiffer elements. Examples include the craniofacial sutures between the bones of the skull, the sutures between the bony plates in shell of turtles and the periodontal ligament between teeth and their sockets. Yet the detailed mechanics of these systems are not fully understood.Turtles are believed to have existed already in the early Triassic, about 200 million years ago. They are thus one of the oldest non-extinct vertebrates. Their shell is therefore a particularly attractive subject for investigation since it has developed and conserved through such an extremely long evolutionary process and has achieved a highly optimized structure.The turtle shell has a ‘sandwich’ structure typical of flat bones like the skull of vertebrates. It consists of two external, relatively thin sheets of dense bone (internal endocortical and external exocortical bone plates) which contain very few voids, and between them a thick and very porous spongy bone layer. At the mid-distance between adjacent ribs the dermal bones are separated by soft sutures which have a unique and complex 3-D shape.The primary function of the shell is to protect the turtle from external trauma, and therefore it has to be stiff. However excessive stiffness may result in microdamage accumulation as a result of everyday activities like minor impact, and decrease the efficiency of respiration and locomotion. We speculate that the structure and architecture of the sutures allow easy deformation of the shell at small loads but cause it to become considerably more rigid at larger loads, reminiscent of composite materials with interlocking elements. We hypothesize that this mechanical property is related to the putative function of the suture in the turtle shell.In order to examine this hypothesis we studied samples obtained from shells of the red eared slider turtle (Chrysemys scripta elegans). We used several imaging techniques (micro-computed tomography, scanning electron microscopy and light microscopy), histology and mechanical testing. Based on these observations we present a concept of the structure-mechanics relationship of the shell, and present a simple mathematical model of the deformation pattern of the suture-containing samples in 3-point bending tests and compare its predictions to our experimental results.
Adhesive Structure of the Freshwater Zebra Mussel, Dreissena polymorpha
Authors: Farsad Nikrooz , Gilbert Trevor W. , Sone Eli D 
Published: August 2010

AbstractThe freshwater Zebra Mussel,Dreissena polymorpha, was accidently released into the Great Lakes approximately 20 years ago. Since then it has spread rapidly, thanks in part to its ability to adhere to hard substrates, resulting in serious environmental and economic consequences. Like the marine mussels, attachment of the Zebra Mussel is achieved by means of its byssus, a series of proteinaceous threads that connect the animal to surfaces via secreted adhesive plaques. While the byssus of the Zebra Mussel is superficially similar to those of its marine counterparts, significant structural and compositional differences suggest that further investigation of the adhesion mechanisms in this freshwater species is warranted. Here we examine for the first time the detailed distribution of DOPA (3,4-dihydroxyphenylalanine)-containing proteins in the Zebra Mussel plaque and threads, as well as the enzyme responsible for their cross-linking. We show that the plaque-substrate interface retains the greatest amount of DOPA after aging, consistent with an adhesive role, while in the threads and bulk of plaque DOPA is presumably cross-linked for cohesive strength. We report also on a remarkably uniform layer ˜10 nm thick on the underside of the plaque, which is most likely responsible for adhesion.
Characterization of Crustacyanin-A2 Subunit as a Component of the Organic Matrix of Gastroliths from the Crayfish Cherax quadricarinatus
Authors: Luquet Gilles , Le Roy Nathalie , Zanella-Cléon Isabelle , Becchi Michel , Bucarey Sergio , Fernandez Maria Soledad , Arias Jose Luis , Guichard Nathalie , Marie Benjamin , Marin Frédéric 
Published: August 2010

AbstractLike the lobsters, some terrestrial crabs and other crayfishes, the Australian red claw crayfish, Cherax quadricarinatus, elaborates in its stomach wall calcium storage structures called gastroliths. For understanding the cyclic elaboration and stabilization of these amorphous calcified structures, we studied the organic matrix (OM) of these paired biomineralizations. After decalcification with acetic acid, we analysed the proteinaceous components of an acetic acid-insoluble fraction by two-dimensional electrophoresis. Nine spots were digested by trpsin and the tryptic peptides were sequenced by nanoLC-nanoESI-MS/MS mass spectrometry. About 100 peptidic sequences were compared to sequences previously registered in the databases. Seven of the partially sequenced organic matrix polypeptides are probably new proteins. Another one corresponds to the previously sequenced protein, GAP65, from Cherax quadricarinatus and the last one, which migrates in electrophoresis at around 25 kDa, presents strong homology with the crustacyanin-A2 subunit of Homarus gammarus.
Superelasticity, Shape Memory and Stability of Nitinol Honeycombs under In-plane Compression
Authors: Shaw John A. , Michailidis Petros A , Triantafyllidis Nicolas , Grummon David S 
Published: August 2010

AbstractLow density Nitinol shape memory alloy honeycombs were fabricated using a new Nb-based brazing method, which demonstrated enhanced shape memory and superelastic properties under in-plane compression. Adaptive, light-weight cellular structures present interesting possibilities for design of new architectures and novel applications. This paper presents an overview of ongoing work to address the multi-scale stability of superelastic, thin-walled, SMA honeycombs and the need for design and simulation tools.
Mechanically Reinforcing Polyacrylate/Polyacrylamide Hydrogels through the Addition of Colloidal Particles
Authors: Baker Bryan A , Murff Rebecca , Milam Valeria T 
Published: August 2010

AbstractPolyacrylamide is a popular material for many bio-related applications ranging from electrophoretic separation to cellular supports. A limitation of polyacrylamide-based hydrogels, however, is their mechanical compliance. The current study examines the effect of colloidal particles as a reinforcing filler phase to enhance the mechanical stiffness of polyacrylamide-polyacrylate hydrogels. Measurements with oscillatory rheology show that for a fixed polymer volume fraction, the presence of colloidal particles with various surface modifications generally results in an increase of the shear storage modulus of the hydrogel-particle composite. Interestingly, this study indicated that no discernable trends can be linked between the values of the shear storage modulus and the particle surface characteristics.
SiGe channels for higher mobility CMOS devices
Authors: Naumann Andreas , Kelwing Torben , Trentzsch Martin , Kronholz Stephan , Kammler Thorsten , Flachowsky Stefan , Herrmann Tom , Kücher Peter , Bartha Johann W 
Published: August 2010

AbstractSilicon germanium (SiGe) is considered to substitute silicon (Si) as channel material of p-type MOSFET in future CMOS generations due to its higher hole mobility. In this work we investigate SiGe channels with a germanium concentration of 23 at% and 30 at%, even though the mobility is expected to be higher with even more germanium in the alloy. Low pressure chemical vapor deposition was used for SiGe deposition. A state of the art CMOS process including high-k dielectric and metal gate electrode was applied for fabrication of sub 50 nm gate length devices. As expected from the SiGe channel conduction and valence band offset the threshold voltage of the devices is influenced. The gate stack was directly deposited onto the SiGe layer consisting of a chemically grown base oxide, hafnium-based dielectric and titanium nitride gate electrode. C-V and I-V measurements show comparable CET and leakage values for the high-k metal gate stack on Si and SiGe channels. The trap density at the channel dielectric interface was determined using the charge pumping technique. The device characteristics of n- and p-MOSFETs with SiGe channels are compared to conventional Si channel devices. Short channel mobility was extracted with the gM,LIN-Method.
Interface quality of atomic layer deposited La-doped ZrO2 films on Ge-passivated In0.15Ga0.85As substrates
Authors: Molle Alessandro , Brammertz Guy , Lamagna Luca , Spiga Sabina , Meuris Marc , Fanciulli Marco 
Published: August 2010

AbstractLa-doped ZrO2 thin films were grown by O3-based atomic layer deposition on III-V (GaAs, In0.15Ga0.85As) substrates. The direct oxide deposition and the insertion of a Ge passivation layer in between the oxide and the substrate are compared in terms of the resulting density of interface traps. An improved electrical quality of the Ge-passivated interfaces concerning the energy region close to the conduction band edge in the semiconductor band-gap is demonstrated through conductance maps at various temperatures and it is attributed to Ga-related interfacial defects.
The Effect of Passivation SiON Layer on the Data Retention Reliability of NAND Flash
Authors: Jang Younggeun , Lee Kwangwook , Kim Eunsoo , Cho Jonghye , Shim Jungmyoung , Kim Sangdeok , Kim Junggeun , Park Sangwook , Lee Byungseok , Kim Jinwoong 
Published: August 2010

AbstractData retention is one of the major device reliabilities of NAND Flash memory. We found that the lower Refractive Index (RI) of the Passivation Silicon Oxynitride (SiON) layer deposited by PECVD, the better data retention behavior was achieved. The hydrogen content and the stress analysis of the films are analyzed to find out which is more important in this case. Generally, when the RI of SiON decreases, both parameters also decrease, so it is impossible to find out which parameter is major factor of data retention. To analyze the effects of two parameters separately, we applied two conditions which had the same H contents but quite different stress values. The final data retention levels are same in both conditions. In addition, even if the layer has the same H content, the retention characteristic is changed by how hydrogen is bonded in the film. In conclusion, the data retention characteristic can be explained by mobile ions generated by the hydrogen weakly bonded in PECVD SiON films in our experiment.
Degradation of Current Gain for Ion Implanted 4H-SiC Bipolar Junction Transistor
Authors: Watabe Yuki , Tajima Taku , Nakamura Tohru 
Published: August 2010

AbstractDegradation of current gain for ion implanted 4H-SiC bipolar junction transistor is described. The influence of bandgap-narrowing to the collector and base currents of the transistor was investigated using ISE-TCAD simulator. Simulated results show good agreement with the measured results, which show that the common emitter current gain of 3.9 is obtained at a maximum base concentration of 2×1017/cm3 and a maximum emitter concentration of 4×1019/cm3 for ion implanted 4H-SiC BJTs.
Development of SiO2 Dielectric Thin Film Prepared by the Low-temperature Solution Process
Authors: Kodzasa Takehito , Uemura Sei , Suemori Kouji , Yoshida Manabu , Hoshino Satoshi , Takada Noriyuki , Kamata Toshihide 
Published: August 2010

AbstractIt is mostly important to develop the fabrication technology of the dielectric thin film with high insulation performance and surface flatness by large-area printing process. We have developed a technique to fabricate a silicon dioxide (SiO2) dielectric thin film by the low temperature solution process. The thin film prepared by about 170°C showed excellent dielectric performance with high resistivity in the order of 10 to the 16 Ωcm and surface flatness with the same degree of thermal oxidized SiO2 thin film on the silicon wafer (RMS=0.15nm). In addition, it is showed that the production of thick film of SiO2 with high dielectric performance and surface flatness is possible by applying over-coating technique. These indicate that this SiO2 production technique is greatly useful for the large-area printed electronics technology.
Parametric CFD Optimization of an APCVD Glass Coating Deposition Module
Authors: Wei Jiuan , Zhang Wei , Salagaj Tom , Strobl Karlheinz 
Published: August 2010

AbstractAtmospheric Pressure Chemical Vapor Deposition (APCVD) thin film coating process is one of the most cost efficient large area thin film coating solutions presently available on the market and can be up to 2.5 times lower in cost compared with a low pressure sputtering system. Advanced materials such as transparent conductive oxides (TCO) used for solar panel manufacturing and for energy saving (Low-E) windows already have been deposited with APCVD Tools incorporating one or more deposition modules. Thin films such as SiO2, TiO2 and F: SnO2, etc have been successfully deposited onto glass sheets. However further improvement in material efficiencies and operational cost reductions are needed to satisfy the growing demand for such highly customized materials. It is also desirable in the future to be able to deposit other material films which traditionally have not yet been available on this lower cost APCVD manufacturing platform, such as zinc oxide (ZnO).To investigate in a quantitative manner the improvement potential for the traditional APCVD deposition module design solution we performed a multidimensional computational fluid dynamics (CFD) parametric study using ANSYS FLUENT V12. As a baseline deposition module design we used a commercially available APCVD deposition module originally developed by Watkins-Johnson for SiO2 deposition trench fill of Si wafers from TEOS, O2 and Ozone from which we could locate in previously published papers for both experiment and CFD modeling results. The CFD software enabled us to perform a full parametric APCVD deposition module design study and allowed us to quantify the efficiency and throughput gains/losses of a wide variety of design change options. The main driver for this study was to learn in a quantitative, cost efficient and time efficient manner about what system design modifications have the potential for significant precursor efficiency increase and/or deposition throughput gain for a particular APCVD deposition process. The results of this study will be utilized to accelerate our proprietary, next generation Off-line and On-line CVDgCoat™ APCVD platform development.
New Copolymers Based on Acenaphto[1,2-b]thieno[3,4-e]Pyrazine for Transistor and Solar Cell Applications
Authors: Boudreault Pierre-Luc T. , Miyaki Nobuyuki , Mondal Rajib , Tang Ming Lee , Bao Zhenan , Leclerc Mario 
Published: August 2010

AbstractWe will show the synthesis of new donor-acceptor copolymers based on 2,7-carbazole or 2,7-dibenzosilole and acenaphtho[1,2-b]thieno[3,4-e]pyrazine. After the synthesis of these new copolymers, we have characterized the materials by UV-vis, DSC, and XRD to determine the degree of organization. Afterward, we have fabricated and investigated field-effect transistors and photovoltaic cells from these polymers. The optimization of the thin film by thermal treatment have led to a field-effect mobility of 0.04 cm2/(V.s) and power conversion efficiency of 0.44%.
Silicon Based Inorganic/Organic Hybrid Materials for Deep Blue PHOLEDs
Authors: Kwon Soonnam , Wee Kyung Ryang , Kang Sang Ook 
Published: August 2010

AbstractDeep blue PHOLED was achieved in the simple device structure of ITO/SiTPA/SiCBP: FIr6 5 wt%/SiTAZ/Liq/Al, where active layers were silicon based inorganic/organic hybrid materials of the types, SiTPA, SiCBP, and SiTAZ for HTL, EML host, and ETL respectively. Silicon incorporation into organic framework not only provided necessary morphological stability, but also engaged enhanced charge transporting capability essential to achieve highly efficient deep blue PHOLEDs. As a result, high performance silicon based HTL, EML host, and ETL materials were developed, exhibiting high charge mobility in the range of 10−4 ∼ 10−3 cm2V−1s−1 and high triplet energy of 2.88 eV, 3.05 eV and 2.84 eV, respectively.Even with the simple four layer device structure of PHOLEDs comprising silicon based active layers, maximum external quantum efficiency (EQE) of 17 % and CIE coordinates of (0.15, 0.22) were achieved. Moreover, an EQE of 15% was recorded at a luminance of 1000 cd m−1, which was the result of reduced efficiency roll-off due to the efficient confinement of FIr6 triplet energy by surrounding silicon based inorganic/organic hybrid materials developed in this work. Structures of inorganic/organic hybrid materials and their photo-physical properties as well as device physics for high performance deep blue PHOLEDs will be presented.