bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Plasma Treatment and TMCTS Vapor Annealing on the Reinforcement of Porous low-k Films
Authors: Kohmura Kazuo , Tanaka Hirofumi , Oike Shunsuke , Murakami Masami , Ono Tetsuo , Seino Yutaka , Kikkawa Takamaro 
Published: June 2019

AbstractA novel process of TMCTS vapor annealing combined with a plasma treatment has been developed for improving the mechanical strength of porous silica films having ultralow dielectric constant. When porous silica films annealed under 1,3,5,7-tetramethylcyclotetrasiloxane (TMCTS) vapor were treated with argon plasma and then re-treated with TMCTS vapor, the mechanical strength (i.e., elastic modulus, hardness) of the films increased significantly. Results of Fourier transform infrared spectroscopy (FT-IR) suggested an accelerative effect resulted from the plasma treatment on the conversion of Si-CH3 and Si-H groups to Si-OH groups. The latter group appears to react faster with TMCTS from the second annealing to form cross-linked polymer network on the porous silica wall surfaces. The resulting cross-linked network is thought to keep the low permittivity and enhance the mechanical strength of the low-k films.
High Strength Low Dielectric Constant Aromatic Thermosets
Authors: Huang Yongqing , Economy James 
Published: June 2019

AbstractContinuing miniaturization of microelectronic devices requires development of low dielectric constant materials to lower the RC delay, power dissipation and crosstalk noise. Although spin-on polymer dielectrics usually have better potential for extendibility to lower dielectric constant (k) values compared to chemical-vapor-deposited dielectrics, their low mechanical properties prevent them from being successfully integrated with copper metal lines.Recent evaluation of a new thermosetting oligomer shows high thermal stability, low moisture pick-up and low dielectric constant. Techniques to optimize the solubility and spin coating characteristics of the oligomer have been developed. The thermally cured polymer displayed a thermal stability up to 480°C in nitrogen and 400°C in air. The cured polymer displayed a dielectric constant of 2.7 at 1 MHz and a breakdown strength larger than 230 V/μm. Nanoindentation testing showed that it had an extraordinarily high Young's modulus of 16.8 GPa and a hardness of 3.5 GPa. By use of porogens, a dielectric constant as low as 1.85 was obtained while still maintaining an acceptable high Young's modulus of 7.7 GPa and hardness of 2.0 GPa. Nanoscratch testing indicated that this material had good adhesion to the Si substrate, and Ta which is a diffusion barrier for copper. These results appear unique compared to all commercially available low-k candidates.
A Novel Organic Low-k Film Deposited by Plasma-Enhanced Co-Polymerization
Authors: Kunimi Nobutaka , Kawahara Jun , Kinoshita Keizo , Nakano Akinori , Komatsu Masashi , Kikkawa Takamaro 
Published: June 2019

AbstractA new organic precursor was designed and synthesized in order to form polymer films having low dielectric constants by a plasma-enhanced co-polymerization (PCP) technology. The organic monomer features a large aliphatic hydrocarbon structure, tricyclodecane (TCD) group. Optimized polymer films deposited from the monomer had dielectric constants less than 2.5. A solid 13C-NMR spectrum showed that the TCD moiety in the precursor was included in the polymer without changing the structure. The effect of the deposition temperature on the film structure was studied by analyzing Raman spectra. It was revealed that the dielectric constant is strongly associated with sp2 carbon content in the TCD-based polymer films.
Analysis of Electromigration-Induced Void Motion and Surface Oscillations in Metallic Thin-Film Interconnects
Authors: Cho Jaeseol , Gungor M. Rauf , Maroudas Dimitrios 
Published: June 2019

AbstractAn analysis is presented of electromigration-induced migration and oscillatory dynamics of morphologically stable void surfaces based on self-consistent numerical simulations of morphological evolution of voids in metallic thin films. As the morphological stability limit is approached, the migration speed of a stable void deviates substantially from being inversely proportional to the void size, a well-known result that is rigorously valid in an infinite conductor with isotropic material properties. A non-linear shape function that includes both current crowding and diffusional anisotropy effects is used to rescale properly the void migration speed resulting in a universally valid relationship for the migration speed as a function of void size. Furthermore, in grains characterized by high symmetry of surface diffusional anisotropy, our analysis predicts the onset of stable time-periodic states for the void surface morphology that correspond to waves propagating on surfaces of voids that migrate along the metallic film at constant speeds.
The Effect of Immersion Sn coating on the Electromigration Failure Mechanism and Lifetimes of Cu Dual Damascene Interconnects
Authors: Yan Minyu , Tu King-Ning , Vairagar Anand V. , Mhaisalkar Subodh G. , Krishnamoorthy Ahila 
Published: June 2019

AbstractIn sub-micron dual damascene Cu interconnects, electromigration occurs mainly along the interfaces between Cu and dielectric cap layer. Many reports have shown that the interface of Cu/dielectric cap is the dominant diffusion path. In-situ electromigration experiments were carried out recently by A. V. Vairagar etal [APPL. PHYS. LETT., 85, 2502 (2004)] to investigate the electromigration failure mechanisms in the upper and lower layers in dualdamascene Cu test structures. It was found that electromigration-induced void first nucleates at locations which are far from the cathode, then moves along the Cu/dielectric cap interface in opposite direction of electron flow, and eventually causes void agglomeration at the via in the cathode end to open the interconnect. In the present study, immersion Sn (20 nm) was employed after CMP and before SiN deposition. All the samples, with a line-width of 0.28 um, were assessed by package level electromigration tests at 300°C under a current density of 3.6MA/cm2. We found that immersion Sn surface treatment effectively introduced the Cu-Sn bonding to the Cu/dielectric interface and has influenced electromigration along the Cu/dielectric interfaces. Failure analysis shows that the samples with these Sn processes have a median-time-to-failure almost 1 order of magnitude larger than the control samples. A careful characterization utilizing FIB and SEM cross-sectional images shows that the failure mechanism has changed due to the Sn surface treatments. After electromigration-induced void nucleation, its movement is blocked by the strong Cu-Sn bonding so that its growth is localized and occurs along grain boundaries. With the increased impedance to surface diffusion, failure analysis seems to indicate that grain boundary diffusion now participates in the void movement and growth, which is proposed to be the reason for the increased lifetime.
Influence of design parameters on dark current of vertically integrated a-Si:H diodes.
Authors: Miazza C. , Wyrsch N. , Choong G. , Dunand S. , Ballif C. , Shah A. , Blanc N. , Lustenberger F. , Kaufmann R. , Despeisse M. , Jarron P. 
Published: June 2019

AbstractImage and particle sensors based on thin film on CMOS (TFC) technology, where a-Si:H detectors are vertically integrated on top of a CMOS chip, basically provide high sensitivity and low dark current densities (Jdark). However, as shown in previous work and as confirmed by the actual measurements, Jdark values depend on the topology of the chip and on the detector structure used.The present paper describes a systematic study carried out, both with test structures on glass and also with a dedicated CMOS test chip designed by CERN. The increase in Jdark is shown to be related to border effects, and especially on the detailed structure of the pixel periphery. In all cases, lower Jdark are obtained when one uses metal-i-p instead of n-i-p configuration detectors. Transferring these results to the standard TFC sensors used by them, the authors have obtained values of Jdark as low as 20 pA/cm2 at -1 V reverse bias.
Monolithic Integration of Electronics and Sub-wavelength Metal Optics in Deep Submicron CMOS Technology
Authors: Catrysse Peter B. 
Published: June 2019

AbstractThe structures that can be implemented and the materials that are used in complementary metal-oxide semiconductor (CMOS) integrated circuit (IC) technology are optimized for electronic performance. However, they are also suitable for manipulating and detecting optical signals. In this paper, we show that while CMOS scaling trends are motivated by improved electronic performance, they are also creating new opportunities for controlling and detecting optical signals at the nanometer scale. For example, in 90-nm CMOS technology the minimum feature size of metal interconnects reaches below 100 nm. This enables the design of nano-slits and nano-apertures that allow control of optical signals at sub-wavelength dimensions. The ability to engineer materials at the nanoscale even holds the promise of creating meta-materials with optical properties, which are unlike those found in the world around us. As an early example of the monolithic integration of electronics and sub-wavelength metal optics, we focus on integrated color pixels (ICPs), a novel color architecture for CMOS image sensors. Following the trend of increased integration in the field of CMOS image sensors, we recently integrated color-filtering capabilities inside image sensor pixels. Specifically, we demonstrated wavelength selectivity of sub-wavelength patterned metal layers in a 180-nm CMOS technology. To fulfill the promise of monolithic photonic integration and to design useful nanophotonic components, such as those employed in ICPs, we argue that analytical models capturing the underlying physical mechanisms of light-matter interaction are of utmost importance.
Infra-Red Photo-Detectors Monolithically Integrated with Silicon-Based Photonic Circuits
Authors: Bradley Jonathan D B , Jessop Paul E , Knights Andrew P 
Published: June 2019

AbstractThe development of monolithic silicon photonic systems has been the subject of intense research over the last decade. In addition to passive waveguiding structures suitable for DWDM applications, integration of electrical and optical functionality has yielded devices with the ability to dynamically attenuate, switch and modulate optical signals. Despite this significant progress, much higher levels of integration and increased functionality are required if silicon is to dominate as a substrate for photonic circuit fabrication as it does in the microelectronic industry. In particular, there exists a requirement for efficient silicon-based optical sources and detectors which are compatible with wavelengths of 1.3 and 1.5μm. While a great deal of work has focussed on the development of silicon-based optical sources, there has been less concentrated effort on the development of a simple, easily integrated detector technology. We describe here the design, fabrication and characterization of a wholly monolithic silicon waveguide optical detector, utilizing an integrated p+-u-n+ diode, which has significant response to optical signals at the communication wavelength of 1.54μm. Measurable infra-red response is induced via the controlled introduction of mid-gap electronic levels within the rib waveguide. This approach is completely compatible with ULSI fabrication. The requirement for the detectors to be integrated with a rib waveguide and hence the guarantee of a long optical signal-device interaction, results in electrical signals of several μAs, even for deep-levels with a small optical absorption cross-section. Further, the rise and fall time of the detectors is compatible with current monolithic, silicon device based, optical switching and modulation operating in the MHz regime. These results suggest that these detectors offer a cost-effective route to signal monitoring in integrated photonic circuits.
Making Wafer Bonding Viable for Mass Production
Authors: Tan Cher Ming , Yu Wei Bo , Jun Wei 
Published: June 2019

AbstractDirect wafer bonding was performed under medium vacuum condition. High bonding strength (larger than 20 MPa) is achieved at the bonding temperature of only 400°C, and the annealing time for complete bonding is less than 5 hours. The bonding efficiency (percentage of the bonded area over entire wafer area) of the medium vacuum wafer bonding (MVWB) is also found to be better than the traditional wafer bonding.Qualitative description of the mechanism of MVWB is proposed in present work. It is believed that the medium vacuum can enhance the out-diffusion of the water molecules and other trapped impurities through the bonding interface which is porous initially. This enhanced diffusion speeds up the chemical reaction for the formation of Si-O-Si, and thus more bonding sites are available before the interface close-up. As a result, we observe an increase in bonding strength, bonding efficiency and the bonding speed.
Surface-Induced Recrystallization of Amorphous Calcium Carbonates to Oriented Calcite Crystals
Authors: Han T. Yong-Jin , Aizenberg Joanna 
Published: June 2019

AbstractEnigmatic functions of amorphous calcium carbonates (ACC) are explored by inducing the formation and the stabilization of spherulitic ACC particles on self-assembled monolayers (SAM) of hydroxy-terminated alkanethiols on Au surface. We demonstrate that the stabilized ACC particles can be induced to crystallize on command to form oriented calcite crystals by introducing a nucleating surface by a means of a secondary SAM surface with carboxylate functionality.
Electropermeabilization of Mammalian Cells Visualized with Fluorescent Semiconductor Nanocrystals (Quantum Dots)
Authors: Sun Yinghua , Vernier P. Thomas , Wang Jingjing , Kuthi Andras , Marcu Laura , Gundersen Martin A. 
Published: June 2019

AbstractElectroporation/electropermeabilization is a non-viral technique for gene transfection and drug delivery. Here, the transfer mechanisms were studied with fluorescent nanocrystals (quantum dots, QDs) in mammalian cells. Interactions of the cell membrane and nanoscale particles were visualized after electric pulse treatment. Responses of human multiple myeloma cells to nanocrystals were tracked for periods up to 7 days. Large particles do not cross the membrane directly after pulsing, even if the membrane is permeabilized to small molecules. Large QDs were trapped on the cell membrane for hours after electroporation and were gradually either excluded or internalized by cells. QD uptake efficiency depended on both particle size and membrane transport activity. These results, consistent with an electropermeabilization model, suggest that enhancing the interactions between the cell membrane and macromolecules may improve the transfer efficiency.
Aminopropyl Embedded Silica Films as Potent Substrates in DNA Microarray Applications
Authors: Saal Kristjan , Plaado Margo , Kink Ilmar , Kurg Ants , Kiisk Valter , Koževnikova Jevgenia , Mäeorg Uno , Rinken Ago , Sildos Ilmo , Tätte Tanel , Lõhmus Ants 
Published: June 2019

AbstractSol-gel derived silane hybrid films composing of (3-aminopropyl)trimethoxysilane–tetramethoxysilane (APTMS-TMOS) have been shown to have properties that make the films suitable for DNA microarray applications. The ability of the films to bind DNA was studied using aminated 25-mer oligonucleotide DNA and 1, 4-phenylenediisothiocyanate linker. The binding of DNA onto the films was shown to depend on films' composition i.e. the binding rate decreased with the decrease of APTMS content in the film. The arrayed primer extension (APEX) analysis showed reversed tendency – fluorescence signals of bound probes increased with the decrease of APTMS content in the film. The background noise was low and the fluorescent probes were clearly outlined. The density of functional amino groups on the films was estimated by fluorescence spectroscopy.
Superparamagnetic Flexible Substrates based on Submicron Electrospun Estane Fibers Containing MnZnFe-Ni Nanoparticles
Authors: Gupta Pankaj , Asmatulu Ramazan , Claus Rick , Wilkes Garth 
Published: June 2019

AbstractFlexible field responsive superparamagnetic substrates were prepared by electrospinning a solution of elastomeric polyurethane containing ferrite nanoparticles (ca. 14 nm) of Mn-Zn-Ni. The flexible mats were characterized in terms of fiber morphology and magnetic properties. Field Emission Scanning Electron Microscopy (FESEM) indicated that the diameter of these composite fibers was ca. 300-500 nm. Furthermore, the back-scattered electron FESEM images indicated agglomeration of the nanoparticles at higher wt% (ca 17-26 wt%) loading in the electrospun fibers. The induced specific magnetic saturation and the relative permeability were found to increase linearly with increasing wt% loading of the ferrite nanoparticles on the submicron electrospun fibers. A specific magnetic saturation of 1.7 – 6.3 emu/g at ambient conditions indicated superparamagnetic behavior of these composite electrospun substrates. Additionally, dielectric constant values of the electrospun fibers were measured to be between 2.3 and 5.8.
Investigations on the Magnetic Properties of High-Coercivity Nd40Fe30Co15Al10B5 Bulk Amorphous Alloys
Authors: Bessais L. , Djëga-Mariadassou C. , Phuc N. X. 
Published: June 2019

AbstractNd40Fe30Co15Al10B5 bulk amorphous prepared by high energy milling shows a coercivity of 8.1 kOe with a Curie temperature of 645 K. The controlled nanocrystallization enhances the coercivity to 20 kOe and the remanence ratio is equal to 0.59. The coexistence of two crystalline magnetic phases, ferromagnetic Nd2(Fe,Co,Al)14B and antiferromagnetic Nd6(Fe,Co,Al)14 are revealed by x-ray diffraction, high-resolution transmission electron microscopy, magnetization measurements, and Mössbauer spectrometry. The grain size for optimal magnetic properties is around 30 nm. The nucleation process may play a leading role in the high magnetic behavior.
Two-Mode Magnetic Switching of a Ferromagnetic Nanowire-Granule-Array Embedded in a Porous Silicon Matrix
Authors: Rumpf K. , Granitzer P. , Krenn H. 
Published: June 2019

AbstractA low-cost method has been developed to produce metallic, perpendicularly oriented ferromagnetic nanowires embedded in crystalline silicon. The mesoporous silicon structure consists of channels with a diameter of about 60 nm and about 30 μm in depth. The electrochemically prepared ferromagnetic nanosystem is a composition of granules and wires which leads to a peculiar magnetic behaviour. The interesting magnetic properties of this bimodal system are investigated by SQUID-magnetometry. The hysteresis loop shows two switching fields at different magnetic fields, one in the low field range and the other one in the high field range. The first switching field at about 500 Oe is due to the magnetization of the granules, the second switching field nearby 5 T (at room temperature) is caused by dipolar coupling of the nanowires which become single domain at high fields due to Bloch Wall motions. This promising ferromagnetic nanocomposite system is not only interesting in basic research but gives raise to a lot of silicon based applications like spin-injection devices and magnetic field sensors.
Characterization of Nanocones Grown During DC Magnetron Sputtering of an ITO Target
Authors: Conley J.F. , McClain D. , Jiao J. , Gao W. , Evans D. , Ono Y. 
Published: June 2019

AbstractA low temperature method for uniform growth of In2O3 nanostructures on Si wafers that does not require separate catalyst materials or template-assistance is investigated. Nanostructures are uniformly deposited on either bare or SiO2 thin film coated Si substrates via DC magnetron sputtering at 200-400°C using a 90% In2O3 / 10% SnO2 (ITO) target. The nanostructures are approximately 500 nm long, sit atop an accompanying underlying 100 nm conductive film, and are conically shaped, with a diameter of about 80 nm at the base, tapering to a point that is capped with a spherical “ball”. X-ray diffraction (XRD) indicates a cubic In2O3 phase. Field emission from the tips is observed at a base pressure of 10-8 Torr with turn-on fields in a range between 45-75 V/cm and threshold fields from 64-105 V/cm. Nanocone growth is investigated with respect to O2 and Ar flow rates, temperature, power, pressure, wafer rotation, and time.
Short-Period Superlattice Structure of Sn-doped In2O3(ZnO)4 and In2O3(ZnO)5 Nanowires
Authors: Na Chan Woong , Bae Seung Yong , Park Jeunghee 
Published: June 2019

AbstractTwo longitudinal superlattice structures of In2O3(ZnO)4 and In2O3(ZnO)5 nanowires were exclusively produced by thermal evaporation method. The diameter is periodically modulated in the range of 50-90 nm. They consist of one In-O layer and five (or six) layered Zn-O slabs stacked alternately perpendicular to the long axis, with a modulation period of 1.65 (or 1.9) nm. These superlattice nanowires were doped with 6-8 % Sn. X-ray diffraction pattern reveals the structural defects of wurtzite ZnO crystals due to the In/Sn incorporation. High-resolution X-ray photoelectron spectrum suggests that In/Sn withdraw the electrons from Zn, and enhance the number of dangling-bond O 2p states, resulting in the reduction of band gap. Photoluminescence exhibit the peak shift of near band edge emission to the lower energy as the In/Sn content increases.
Morphology and Properties of Tetraleg ZnO Nanostructures Fabricated by Zn-Powder Evaporation without Catalysts at Lower Temperature
Authors: Zhang Yue , Huang Yunhua , He Jian , Dai Ying , Wang Sen , Zhou Cheng 
Published: June 2019

AbstractBy simply controlling temperature and atmosphere, tetraleg ZnO nanostructures with different morphologies and sizes have been fabricated respectively through pure zinc powder evaporation without catalysts at temperature of 600∼800 oC. The growth mechanisms of the nanostructures were proposed and discussed. Photoluminescence spectra showed a UV and green emission peaks at room temperature. Field emission measurements revealed that the turn-on field is very low and the emission current density is relative to the morphology and size. Such ZnO nanostructures are likely to be candidates as building blocks for constructing photonic and field emission crystals.
Nonaqueous Synthesis of Barium Titanate Nanocrystals in Acetophenone as Oxygen Supplying Agent
Authors: Niederberger Markus , Garnweitner Georg 
Published: June 2019

AbstractSolvothermal reaction of a mixture of metallic barium and titanium isopropoxide in acetophenone leads to the formation of barium titanate nanocrystals. XRD measurements prove the presence of cubic BaTiO3 with traces of BaCO3 as side product. According to TEM investigations, the particles exhibit a nearly spherical particle shape with diameters ranging from 10 to 15 nm. However, due to the lack of any stabilizers, the particles are slightly agglomerated. NMR analysis of the obtained reaction solution shows that aldol condensation reactions of acetophenone and in situ formed acetone provide the water necessary for inducing crystallization and nanoparticle formation.