Interconnect Applications Research Articles

Oxidation and Cr-evaporation behavior of MnCo based spinel and composite coated AISI 430 steel

This work investigates the importance of the chemical composition and porosity of the coating on reducing the oxidation and Cr-evaporation rate of AISI 430 steel in O2-5%H2O at 800 °C for solid oxide fuel cell (SOFC) interconnect applications. Electrophoretic deposition (EPD) is used to deposit eight different coatings. Mn1.25−0.5xCo1.75−0.5xMxO4 (M = Fe, Cu, and Fe-Cu; and X = 0 and ~0.3) powders are synthesized by the glycine nitrate process (GNP) and applied as spinel (without La2O3) or composite (with La2O3) coatings. The coatings initially show porous structure, and the coating density improvement depends on coating composition. The coating porosity for composite co-doped Fe-Cu MnCo spinel (MCFeCuL) is 28% less than MnCo spinel (MC) after 504 h. All coated samples show lower oxidation and Cr-evaporation rates than uncoated samples. The parabolic oxidation rates are lower for composite coated than the spinel ones, possibly due to the formation of LaCrO3 reducing Cr outward diffusion. Composite MnCo-La2O3 (MCL) shows the lowest oxidation rate. In contrast, coating effectiveness in reducing Cr-evaporation depends on coating density. Cu-doped coatings show less coating porosity with better oxidation and Cr-evaporation behavior than Fe-doped coatings. All coated samples form a densified layer at the thermally grown oxide (TGO) scale/coating interface, playing a crucial role in oxidation resistance and migration of Cr from the TGO scale to the coating. The changes in Cr-evaporation fluxes depending on coating porosity and pore size are calculated and compared with Cr-loss rate measurements. Among the coatings, composite Cu-doped MnCo spinel (MCCuL) and MCFeCuL show better performance than the other ones. This study shows that it is possible to decrease coating porosity and improve the performance of MnCo spinel coatings against corrosion and Cr-evaporation without two-step sintering (at T ≤ 900 °C) procedures.

Self-Organizing and Self-Explaining Pervasive Environments by Connecting Smart Objects and Applications

In the past decade, pervasive environments have progressed from promising research concepts to available products present in our everyday lives. By connecting multiple smart objects, device ensembles can be formed to assist users in performing tasks. Furthermore, smart objects can be used to control applications, that, in turn, can be used to control other smart objects. As manual configuration is often time-consuming, an automatic connection of the components may present a useful tool, which should take various aspects into account. While dynamically connecting these components allows for solutions tailored to the needs and respective tasks of a user, it obfuscates the handling and ultimately may decrease usability. Self-descriptions have been proposed to overcome this issue for ensembles of smart objects. For a more extensive approach, descriptions of applications in pervasive environments need to be addressed as well. Based on previous research in the context of self-explainability of smart objects, we propose a description language as well as a framework to support self-explaining ambient applications (applications that are used within smart environments). The framework can be used to manually or automatically connect smart objects as well as ambient applications and to realize self-explainability for these interconnected device and application ensembles.

Low-crosstalk laser-direct-writing FI/FO device for 8×100-Gbps optical interconnection.

Fan-in/fan-out (FI/FO) device with low crosstalk is essential for weakly coupled short-reach optical interconnect based on multicore fibers (MCF), for which the laser-direct-writing (LDW) technique is one of the preferred fabrication schemes. In this paper, the influence of FI/FO crosstalk on short-reach intensity-modulation/direction-detection MCF optical interconnection is firstly evaluated, and the crosstalk related to different refractive-index profiles of waveguides and misalignment is analyzed for LDW-FI/FO devices. Then low-crosstalk compact LDW-FI/FO devices matching 8-core MCF are fabricated, adopting multiple-scan method for waveguides with a flat-top refractive-index profile and aberration correction method for precise alignment. Owing to the low crosstalk, 8×100-Gbps optical interconnection over 10-km MCF is experimentally demonstrated with only 0.5-dB penalty compared to 10-km G.652D single-mode fiber transmission. Simulation results indicate that the transmission reach can be further extended to over 40 km. The proposed prototype system with low crosstalk is promising for high-speed optical interconnection applications.

Edge Engineered Graphene Nanoribbons as Nanoscale Interconnect: DFT Analysis

Density functional theory (DFT) with non-equilibrium Green's function (NEGF) formalism and HSPICE simulator have been used to analyse the effect of elemental oxygen atom passivation on the structural, electronic and transport properties of Graphene Nanoribbons (GNRs). The analysis of delay, power dissipation, crosstalk effect, stability and frequency analysis has also been performed to understand its interconnect application. The present study includes all the possible morphologies of zigzag and armchair edge states of GNRs with oxygen and hydrogen passivation. The structural stability of GNRs, analysed in terms of binding energy <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$(E_{binding})$</tex-math></inline-formula> observed that the Zigzag graphene nanoribbon (ZGNR) with both edge oxygen passivated, is the most stable configuration, where stability of the configuration increases with Oxygen concentration. Further, fro <uri xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">text</uri> m the bandstructure and density-of-states calculations, it has been observed that considered 6 atom wide and hydrogen passivated Armchair GNR (AGNR) is semiconducting in nature, whereas, with same width hydrogen passivated ZGNR is metallic. On the other hand, passivation of AGNR with increasing concentration of oxygen form them to metallic in nature. Based on the enhanced metallicity and increment in fermi velocity due to passivation of GNRs with oxygen, these structures may be a potential candidate for interconnects. Their computed electron transport properties, dynamical parameters, delay, power delay product and crosstalk induced delay confirms that the zigzag GNR with both the edges passivated with oxygen (O-ZGNR-O) can be considered as best contender for interconnect application due to its remarkable electrical and thermal transport in comparison to other GNR's. The O-ZGNR-O shows lowest value of kinetic inductance and quantum capacitance of. 01032H/m and 2.21 nF/m respectively with higher stability and higher immunity to crosstalk effect in comparison to other proposed GNRs, which is required for nanoscale interconnects. The relative stability of GNRs have been analyzed in terms of nyquist plot with different interconnect lengths. The results suggest that O-ZGNR-O have lowest delay and power dissipation with higher stability, hence defends its application for interconnect application.

Flatness of interconnected linear systems and applications to electrical systems

In this paper, we completely describe flatness of the simplest class of interconnected systems: we consider an interconnection of (controllable) single-input linear subsystems in dimension two with a star topology and a linear interconnection dynamics (with no inputs acting directly on the interconnection variable). First, we observe that even if each subsystem is flat, flatness of the global interconnected system is not necessarily preserved. Then, we give necessary and sufficient verifiable conditions for flatness of the interconnected system. When the interconnected system is flat, we analyze how its flat output depends on the interconnection variable and how it can be expressed in function of the flat outputs of each subsystem. Finally, we show how our results can be applied to electrical power systems.

Communication-Efficient Federated Learning for Digital Twin Systems of Industrial Internet of Things

With the rapid development and deployment of Industrial Internet of Things technology, it promotes interconnection and edge applications in smart manufacturing. However, challenges remain, such as yet-to-improve communication efficiency and trade-offs between computing power and energy consumption, which limits the application and further development of IIoT technology. This paper proposes the digital twin systems into the IIoT to build model between physical objects and digital virtual systems to optimize the structure of IIoT. And we further introduce federal learning to train the digital twins model and to improve the communication efficiency of IIoT. In this paper, we first establish the digital twins model of IIoT based on industrial scenario. Moreover, to optimize the communication overhead allocation problem, this paper proposes an improved communication-efficient distribution algorithm, which speeds up the training performance of federated model and ensures the performance of industrial system model by changing the update training mode of client and server and allowing some industrial equipment to participate in federated training. This paper simulates the real-word intelligent camera detection to validate the proposed method. Comparing our proposed method with the existing traditional methods, the results show the advantages of the proposed method can improve the communication performance of the training model.

Properties of Ultrathin Molybdenum Films for Interconnect Applications

Properties of Ultrathin Molybdenum Films for Interconnect Applications

Preliminary investigation on the correlation between mechanical properties and conductivity of low-density polyethylene/carbon black (LDPE/CB) conductive polymer composite (CPC)

The insulating nature of a polymer can be changed to electrically conductive by incorporating conductive fillers within the polymer matrix to form a conductive polymer composite (CPC). One of the potential application of CPCs are in the area of flexible electronic interconnect application. Nevertheless, the correlation between the electrical conductivity and mechanical properties of CPCs such as tensile was found to be limited. Therefore, this paper is aimed to report the preliminary investigation on the correlation between conductivity and mechanical properties of a low-density polyethylene (LDPE) incorporation with conductive filler which is carbon black (CB. It was observed that the tensile strength was decreased by up to 29.4% and the elongation of break was decreased by up to 90.6% at higher CB loading compared to pure LDPE. Nonetheless, the modulus of elasticity and the electrical conductivity of the composites were increased by up to 150.5% and 16.4% at higher CB loading respectively. Moreover, it was found that the effect of CB additions on the tensile modulus was greater compared to the conductivity of the CPCs.

Improvement of Thermal Stability of NiAl Via Employing Al Capping Layer for Advanced Interconnect Applications

Improvement of Thermal Stability of NiAl Via Employing Al Capping Layer for Advanced Interconnect Applications

Contact Geometrical Study for Top Emitting 980 nm InGaAs/GaAsP Vertical-Cavity Surface Emitting Lasers

Geometrical contacts of a double mesa structure with 16 rows ×15 columns arrays of top emitting GaAs based 980 nm vertical cavity surface emitting lasers (VCSELs) are fabricated and characterized. In this paper, 5 strained In0.22Ga0.78As/Ga0.9AsP0.1 quantum wells (QWs) within λ/2 thick cavity have been employed. The top and the bottom epitaxially grown mirrors are based on the linear graded Al0.9Ga0.1As/GaAs distributed Bragg reflectors (DBRs) with 20.5 and 37 periods, respectively. Static parameters including threshold currents, rollover currents, maximum optical output power and wall-plug efficiency are extracted from light out power-current-voltage (LIV) of VCSELs with fixed oxide aperture diameter of ∅~ 6 μm and various mesa2 diameters. In addition, spectral emission for 980 nm VCSELs of oxide aperture between ∅~ 6 and 19 μm and with fixed ∅~ 6 μm and different bias currents are analyzed. The highest optical output power of around 33 dBm is observed at bias current of 0.8 mA for short−reach optical interconnect applications.

Polarization-tunable compact plasmonic wavelength demultiplexers based on Fano nanoantennas

A compact plasmonic wavelength demultiplexer is an essential prerequisite for practical applications, including the next-generation on-chip devices, near-field optical trapping, and micromanipulation. However, alleviating the polarization dependence of the wavelength demultiplexers remains one of the most challenging issues in realizing such a plasmonic device. Here we propose a gold disk-slit-based compact Fano-type nanoantenna capable of launching surface plasmon polaritons (SPPs) directionally when irradiated under different wavelengths of light, realizing a wavelength demultiplexing function. More importantly, our simulation results show that the shortage of requirement of specific light polarization direction excitation in such wavelength demultiplexers can be circumvented. Furthermore, it is found that the output channel of the SPP can be switched in multiple directions under different polarization excitations. In addition, the results show that the applicable wave band of the wavelength demultiplexing device can be flexibly adjusted by changing the size of the nanoantenna. The technique of introducing the polarization-tunable function into the wavelength demultiplexers in the plasmonic interconnect application enhances the freedom of information transmission and offers a promising building block for future high-speed and high-bandwidth on-chip optical communication.

Understanding electron transport in halogenated graphene nanoribbons and possible application as interconnects

To analyse the suitability of zigzag graphene nanoribbons (ZGNRs) as interconnects, the influence of halogen (F, Cl, Br, and I) passivation on ZGNRs has been analysed in terms of structural stability, electron transport, and thermal conductivity, as well as the performance parameters of the interconnects. The computation is performed using first-principle density functional theory with a non-equilibrium Green’s function approach, while the performance parameters of the interconnects such as delay and power delay product are computed using a HSPICE simulator tool. The formation energy analysis confirms the stability trend for halogen-passivated ZGNRs as F > Cl > Br > I. With moderate stability, the I- and Br-passivated ZGNRs have relatively better current–voltage characteristics in comparison to F and Cl. However, the Cl-passivated ZGNRs have relatively better interconnect parameters in comparison to other proposed halogenated systems (one edge and both edges), measured in terms of kinetic inductance and quantum capacitance. Another requirement of any good interconnect is less delay and less average power, which have also been computed and found to be relatively better in the case of Cl-passivated ZGNRs. Thus, among the halogen-passivated GNRs tested, those that are Cl-passivated defend their selection for interconnect applications well.

Aerosol Jet Printing of Graphene and Carbon Nanotube Patterns on Realistically Rugged Substrates.

Direct-write additive manufacturing of graphene and carbon nanotube (CNT) patterns by aerosol jet printing (AJP) is promising for the creation of thermal and electrical interconnects in (opto)electronics. In realistic application scenarios, this however often requires deposition of graphene and CNT patterns on rugged substrates such as, for example, roughly machined and surface-oxidized metal block heat sinks. Most AJP of graphene/CNT patterns has thus far however concentrated on flat wafer- or foil-type substrates. Here, we demonstrate AJP of graphene and single walled CNT (SWCNT) patterns on realistically rugged plasma-electrolytic-oxidized (PEO) Al blocks, which are promising heat sink materials. We show that AJP on the rugged substrates offers line resolution of down to ∼40 μm width for single AJP passes, however, at the cost of noncomplete substrate coverage including noncovered μm-sized pores in the PEO Al blocks. With multiple AJP passes, full coverage including coverage of the pores is, however, readily achieved. Comparing archetypical aqueous and organic graphene and SWCNT inks, we show that the choice of the ink system drastically influences the nanocarbon AJP parameter window, deposit microstructure including crystalline quality, compactness of deposit, and inter/intrapass layer adhesion for multiple passes. Simple electrical characterization indicates aqueous graphene inks as the most promising choice for AJP-deposited electrical interconnect applications. Our parameter space screening thereby forms a framework for rational process development for graphene and SWCNT AJP on application-relevant, rugged substrates.

A Survey of Instruments and Institutions Available for the Global Governance of Artificial Intelligence

<bold xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Emerging Technologies Have</b> always challenged traditional regulatory regimes <xref ref-type="bibr" rid="ref1" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">[1]</xref> . This is not new nor is this tension likely to change anytime soon given the increasing speed at which embryonic technologies are emerging into the market <xref ref-type="bibr" rid="ref2" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">[2]</xref> . Some of these technologies, such as autonomous vehicles or drones, can be effectively regulated at the national level due to clearly defined jurisdictional boundaries and the existence of relevant national and state/provincial regulatory agencies that oversee their conventional counterparts. While the entry of these technologies into the market will challenge regulators and policymakers and may require tweaking of existing regimes, we argue that these technologies, and the products that they enable, will not require a sui generis response at the national and supranational levels. The same cannot be said for artificial intelligence (AI) and the myriad of interconnected and interwoven applications made possible by AI.

Stability- and Crosstalk-Based Performance of Multi- and Double-walled Mixed CNT Bundles as Interconnect for Next-Generation Technology Nodes

The temperature-dependent modeling technique (in the temperature range of 200–500[Formula: see text]K) for a mixed class of carbon nanotube (CNT) bundle interconnects is proposed. The equivalent single conductor (ESC) transmission line models of multi-walled carbon nanotube (MWCNT) and double-walled carbon nanotube (DWCNT) are combined to develop multiple single conductor (MSC) model of mixed CNT interconnects. Various possible arrangements of densely packed MWCNT and DWCNT bundles (MDCB) are considered to form different types of mixed CNT bundle structures (MDCB-1, MDCB-2, MDCB-3 and MDCB-4). The integrated circuit emphasis simulation is performed and the performances of these mixed CNT bundle interconnects are investigated in terms of propagation delay (with and without crosstalk), power dissipation, power-delay product (PDP). Switching times, overshoot voltages and Nyquist plots are analyzed to check the stability of these mixed CNT structures for global interconnect length for 32-nm, 22-nm and 16-nm technology nodes. It is observed that the MDCB-1 structure yields the most promising result in all aspects for interconnect applications in the near future.

Preparation and performance of (Co, Mn)3O4 spinel coating on Crofer alloy by composite electrodeposition and step‐heating thermal conversion

The preparation and performance improvement of the spinel coating on the surface of ferritic alloy is of wide interest for its application in the metallic interconnects of the solid oxide fuel cells (SOFCs). The CoMn2O3 composite coating is prepared on the surface of the Crofer alloy by the composite electrodeposition method. A step‐heating thermal conversion process is subsequently used to convert the composite coating into a spinel coating, while a direct‐heating process is implemented as the control experiment. Isothermal oxidation tests are then carried out for the prepared samples in order to present the high temperature performance. Scanning electron microscopy (SEM), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), and area‐specific resistance (ASR) are used to analyze the properties of the matrix and coatings. The experimental results reveal that the coatings by step‐heating thermal conversion exhibit better performance of electrical conductivity and oxidation resistance than the coatings by direct‐heating process. Furthermore, with the increase of oxidation time, the atomic proportion of Cr element diffusing to the surface of the matrix is maintained at about 3%–4% for the samples with spinel coatings by step heating, which effectively prevent the Cr volatilization in the matrix. The preparation of spinel coatings on the ferritic alloy by composite electrodeposition and step‐heating thermal conversion is helpful to stimulate new ideas for the development of reliable and cost‐effective metallic interconnect.

(Invited) Area-Selective Atomic Layer Deposition for Interconnect Applications

As the semiconductor industry is approaching the 5nm node technology, conventional patterning schemes cannot meet the ever-increasing requirements for alignment imposed by device miniaturization. Area-Selective Deposition (ASD) can potentially alleviate such manufacturing challenges by enabling bottom-up material deposition. The most used and successful approach to achieve ASD envisage a combination of Atomic Layer Deposition (ALD) and surface passivation, such as, self-assembled monolayer (SAM).Among the potential applications, dielectric on dielectric (DoD) ASD emerged as one of the most important for multilayer nano interconnects (e.g.: enabling fully self-aligned vias). In this context, along with the difficulties encountered in preserving a confined material growth, the challenges extend to the fact that the deposited dielectric must exhibit well-defined properties, such as low-dielectric constant. Indeed, the integration an interconnect dielectric deposition process in an ASD scheme is arduous. Vapor-phase deposition of SiO2-like materials typically requires high process temperature as well as strong oxidants or O2-plasma. These are not compatible with the organic passivation films exploited to create well-distinguished local surface chemistries, which is essential to enable selective-material deposition.In this talk, 1-octadecanethiol (ODT) well-known selective chemisorption on Cu over SiO2 is exploited to achieve AS-DoD deposition and understand the surface-driven mechanism that enables a selective material growth. In addition, the proposed ASD scheme in combination with nanoscale adhesion force characterization is used to tackle a critical lack in ASD metrology: monitoring the passivation film directly on patterned substrate. Finally, the challenges and results obtained as an ODT-compatible dielectric deposition process for interconnect applications are discussed in this talk.ASD enabled by metal passivation for Hf3N4, Hf-Silicate, Al2O3, and Al-silicate ALD are explored and presented on Cu/SiO2 patterned substrates, with critical dimension as low as 10nm.

Fe doped Ni–Co alloy by electroplating as protective coating for solid oxide fuel cell interconnect application

To obtain higher electrical conductivity and lower area specific resistance (ASR), the 10% Fe doped Ni–Co (NCF) alloy was prepared on SUS 430 steel substrate by electroplating for solid oxide fuel cells (SOFCs) interconnects application. Then, the SUS 430 steels and NCF coated steels were oxidized at 800 °C. The microstructure and oxide phase of samples were tested by scanning electron microscope (SEM) with energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). These results proved that the NCF coated steel achieved the lower oxidation rate of 9.28 × 10−14 g2cm−4s−1 and ASR of 14.72 mΩ cm2.

Lisen&Curate: A platform to facilitate gathering textual evidence for curation of regulation of transcription initiation in bacteria

The number of published papers in biomedical research makes it rather impossible for a researcher to keep up to date. This is where manually curated databases contribute facilitating the access to knowledge. However, the structure required by databases strongly limits the type of valuable information that can be incorporated. Here, we present Lisen&Curate, a curation system that facilitates linking sentences or part of sentences (both considered sources) in articles with their corresponding curated objects, so that rich additional information of these objects is easily available to users. These sources are going to be offered both within RegulonDB and a new database, L-Regulon. To show the relevance of our work, two senior curators performed a curation of 31 articles on the regulation of transcription initiation of E. coli using Lisen&Curate. As a result, 194 objects were curated and 781 sources were recorded. We also found that these sources are useful to develop automatic approaches to detect objects in articles by observing word frequency patterns and by carrying out an open information extraction task. Sources may help to elaborate a controlled vocabulary of experimental methods. Finally, we discuss our ecosystem of interconnected applications, RegulonDB, L-Regulon, and Lisen&Curate, to facilitate the access to knowledge on regulation of transcription initiation in bacteria. We see our proposal as the starting point to change the way experimentalists connect a piece of knowledge with its evidence using RegulonDB.

Electrical and mechanical properties of Au–Si bonds for 3D interconnect applications

Driven by high-density and high-reliability demands on three-dimensional (3D) interconnections, electrical and mechanical properties of interconnection structures have been paid more attention. Aiming at the novel enable-3D interconnections realized by Au–Si wafer bonding, this study demonstrates the design, fabrication and test results of testing structures for dimension-define parameters of Au–Si bonds. In order to measure closely-realistic ohmic contact resistances of Au–Si bonds after wafer bonding processes implemented under certain bonding pressures and temperatures, the convex Si structures formed by the local oxidation of silicon process have been designed. Therefrom the specific contact resistance values of Au–Si bonds have been measured as 3.9–8.1 × 10−10Ω m2 for different contact radii (3–20 μm), which indicates the low-resistance potentiality for Au–Si bonds applied on 3D interconnections. On the other hand, two findings on bonding strengths are summarized from finite element simulations and tensile experiments: (a) Au–Si bonding strengths of circular bonding patterns (35–75 MPa) are superior to the ones of square bonding patterns (18–30 MPa) due to the stress concentration phenomenon on four corners of square bonding patterns; (b) there is an inverse relationship between bonding strengths and bonding areas owing to uneven stress distributions in bonding structures. Overall, this study provides a basic optimization design strategy at electrical and mechanical levels for 3D interconnections actualized by Au–Si bonding. Incidentally, these introduced analysis methods are also feasible for homologous Si-based eutectic bonding techniques to extend the forms of 3D interconnections.