Interconnect Layers Research Articles

Survey on IoT Privacy, Data Protection and Security Concerns

Abstract: The proliferation of Internet of Things (IoT) devices has transformed the way we interact with the digital world, offering unprecedented connectivity and convenience. However, this rapid expansion brings forth profound challenges concerning privacy, data protection, and security. This survey paper comprehensively explores the multifaceted landscape of IoT, dissecting its architecture, and delving into the intricate web of concerns surrounding user privacy, data safeguarding, and system security.Beginning with an examination of the IoT architecture, we dissect the interconnected layers, ranging from sensors to cloud platforms, illustrating the intricate pathways of data flow. The survey meticulously unfolds the privacy challenges embedded in the constant data collection, tracking, and profiling mechanisms intrinsic to IoT devices. Drawing on real-world examples, we underscore the tangible consequences of privacy breaches and the potential erosion of user trust.In the realm of data protection, we delve into the complexities of safeguarding data integrity, confidentiality, and availability within the IoT ecosystem. Regulatory frameworks, notably the General Data Protection Regulation (GDPR), are scrutinized for their impact on shaping data protection practices. Concurrently, the paper uncovers common security threats in IoT, emphasizing vulnerabilities in devices and the looming risks associated with unauthorized access and data breaches.Navigating through the regulatory landscape, the survey provides an overview of existing standards and regulations governing IoT. Case studies spotlight instances of privacy breaches, data protection lapses, and security vulnerabilities, offering practical insights into the implications of these incidents. Mitigation strategies, encompassing encryption, authentication, and access control, are explored to address the identified concerns.As the paper concludes, it synthesizes the key findings, emphasizing the urgency of continued efforts to fortify IoT against privacy, data protection, and security challenges. The survey anticipates future trends and challenges, offering a roadmap for researchers, policymakers, and industry stakeholders to collectively forge a secure and privacy-aware IoT landscape.

Deformation microstructures of low- and high-strain epidote-blueschist (Ryukyu arc, Japan): Implications for subduction interface rheology

We present field and microstructural data from an exhumed subduction complex in the Ryukyu arc, Japan, where epidote-blueschist, Triassic, Tomuru metamorphic rocks with block-in-matrix structure crop out. With the aim to constrain epidote-blueschist rheology, we investigate fabric development and infer deformation mechanisms of blocks and matrix through microstructural analyses on the main fabric-forming minerals: glaucophane, epidote and albite. The blocks have a poorly developed, discontinuous foliation. In contrast, the matrix has a well-developed, continuous foliation. Glaucophane is the principal foliation-forming phase, arranged in interconnected layers that surround epidote and albite, which suggests that glaucophane controls epidote-blueschist rheology. Deformation mechanisms inferred from petrographic and electron backscatter diffraction (EBSD) analysis are similar in blocks and matrix, with glaucophane deformed by diffusion creep accompanied by reaction-driven creep, albite by diffusion creep, and epidote by brittle fracture and incipient dislocation creep, based on degrees of internal misorientations, lattice preferred orientation (LPO) development and grain size. During deformation, shear stress must have been relatively low, which is implied by the predominance of diffusion and reaction creep as the dominant deformation mechanisms, and by the small viscosity contrast between blocks and matrix, reflected by their similarity in dominant deformation mechanism.

The Enrichment of Whey Protein Isolate Hydrogels with Poly-γ-Glutamic Acid Promotes the Proliferation and Osteogenic Differentiation of Preosteoblasts.

Osseous disease accounts for over half of chronic pathologies, but there is a limited supply of autografts, the gold standard; hence, there is a demand for new synthetic biomaterials. Herein, we present the use of a promising, new dairy-derived biomaterial: whey protein isolate (WPI) in the form of hydrogels, modified with the addition of different concentrations of the biotechnologically produced protein-like polymeric substance poly-γ-glutamic acid (γ-PGA) as a potential scaffold for tissue regeneration. Raman spectroscopic analysis demonstrated the successful creation of WPI-γ-PGA hydrogels. A cytotoxicity assessment using preosteoblastic cells demonstrated that the hydrogels were noncytotoxic and supported cell proliferation from day 3 to 14. All γ-PGA-containing scaffold compositions strongly promoted cell attachment and the formation of dense interconnected cell layers. Cell viability was significantly increased on γ-PGA-containing scaffolds on day 14 compared to WPI control scaffolds. Significantly, the cells showed markers of osteogenic differentiation; they synthesised increasing amounts of collagen over time, and cells showed significantly enhanced alkaline phosphatase activity at day 7 and higher levels of calcium for matrix mineralization at days 14 and 21 on the γ-PGA-containing scaffolds. These results demonstrated the potential of WPI-γ-PGA hydrogels as scaffolds for bone regeneration.

Effects of two mild amino acids on benzotriazole residue desorption during cobalt post-chemical mechanical polishing cleaning: Experimental and theoretical studies

During the polishing process of the cobalt (Co) interconnect layer, the corrosion inhibitor in the polishing solution will leave an organic residue on the polished cobalt surface, which needs to be removed by the post-chemical mechanical polishing (CMP) cleaning process. However, given the active chemical properties of cobalt, the potent and corrosive complexing agents in traditional cleaning solutions have the drawback of generating new corrosion defects on the cobalt surface. In this study, an eco-friendly cleaning solution is developed utilizing tetraethyl ammonium hydroxide (TEAH), deionized water, and either sarcosine or serine, thereby ensuring the absence of any additional introduction of metal impurities. The removal effect of the cleaning solution on BTA was tested using atomic force microscopy (AFM) and X-ray photoelectron spectrometer (XPS). The results demonstrate that post-CMP cleaning with either sarcosine or serine yielded a cobalt surface with reduced roughness (2.78 nm and 2.63 nm), diminished Co-BTA content (10.6% and 9.5%), and a lowered contact angle (44.3° and 37.9°). To elucidate the mechanism of post-CMP cleaning, electrochemical measurements and molecular dynamics were employed. Initially, in the cleaning solution with a pH of 10.4, the adsorption of BTA and cobalt is minimized. Subsequently, as serine permeates through the BTA residue layer, the desorption of BTA is expedited through competitive adsorption. These findings contribute valuable insights into the mechanism of residue removal in post-CMP cleaning processes.

Nanoporous Cu-Sn Intermetallic Material for Interconnects in Electronic Packaging

Nanostructured and nanoparticulate Cu-based materialshave emerged as viable replacements of conventional solder materials for realizing high-performing and reliable interconnection in today's 2.5D/3D electronic packaging. Unlike the traditional interconnects, those materials offer better compliance during the overall packaging routines. Owing to their highly developed surface area resulting of their uniform interconnected porosity, said nanomaterials also enable joint formation by sintering by thermal compression realized at high pressure and at much lower temperatures compared to bulk counterparts. Recently, sintering of nanoporous (np) Cu was demonstrated under high pressure and temperature after initial pre-treatment in acid for surface oxide removal. Separately, other studies have been focused on the attachment of Cu pillars to pads by using nanoparticulate Cu pastes as sintering material. The ultimate goal is to develop materials that facilitate a highly effective and durable chip-to-substrate interconnection.In this report, we discuss the development and use of nanoporous uniform and continuous CuSn films for low-temperature joint formation. The novelty of this work is realized through the introduction of tin (Sn) to work along with the np-Cu structure for ensuring lower sintering temperatures with a goal of producing packaging interconnects based on CuSn intermetallic compound (IMC). The addition of Sn to the np-Cu system is performed using a bottom-up, all-electrochemical synthetic approach (see Figure 1). The method is founded on the initial synthesis of thin films of np-Cu by dealloying of Cu-Zn alloys, followed by a conformal coating with a thin layer of Sn. The main goal of the proposed approach is to form a np-CuSn composite that upon sintering at high temperature and pressure, transitions into a densely compressed Cu3Sn IMC bonding material. Realized accordingly as interconnect layer, said material ensures good stability at high current densities (greater than 1×105 A ⋅ cm2 ) and low electrical resistivity (equal or less than 8.5 µΩ ⋅ cm).The synthetic details and then the applicability of the Cu-Sn nanomaterials obtained using the approach for synthesis of a low-temperature joint formation material are also discussed. The Sn-coating process was administered by galvanic pulse plating, which was optimized to provide a conformal Sn coating and thus, to retain the initial np-Cu overall porous structure. Another optimization effort was made for ensuring a Sn atomic fraction that allows for the formation of Cu6Sn5 IMC. After the optimization process for determining the necessary plating conditions for reaching mostly Cu6Sn5 composition ratio, the material was subjected to sintering at temperatures in the range from 300ºC to 200oC, and at a pressure of 20 MPa. We found that the joints formed were heavily densified and consisted mainly of Cu3Sn IMC. The report presents the new approach as a facile and cost-effective method for synthesizing nanostructured Cu-Sn films as viable candidates for a new-generation of interconnect materials together with the demonstration of assembly processes that optimize robustness and reliability. The discussion also shows the proposed approach’s applicability by realization of low-temperature sintering of nanostructured CuSn films in pre-designed fine pitch assemblies. Figure 1: Schematic representation demonstrating key steps of the approach for synthesis of np-CuSn composites. Figure 1

Structuring Japanese editorials along the lines of rhetorical structure annotations: issues and discoveries

This paper is a result of a practical experiment in annotating the rhetorical structure of three editorial articles from the leading Japanese newspapers, focused on connectors and their role in the text. Annotation work was carried out along the general lines of existing techniques, at the same time calling for substantial adjustments in both the relations’ taxonomy and orientation, and also the principles of breaking down discourse units. These methodological findings are reviewed in the conclusive part. The main difficulty in representing the overall text structure is whether it can be convincingly represented in the form of a tree (as is expected from a pragmatically organized text). Some in-depth analysis shows that apart from rhetorical relations between discourse units a complex networks of holistic structure (macrostructure), intentional structure, referential network are of not less importance in the unity of the text. Notional structure in the basis of the reader’s comprehension also comes into the bargain, as well as the author’s efforts to influence and direct it overtly or covertly. An RST tree would only be a part of this totality. Appended are tentative graphical representations of an approximated tree structure as well as graphs covering the text’s intentional structure, divided into interconnected layers. This experiment highlighted major peculiarities of a newspaper editorial as one type of text. They are seen as rooted in the pragmatical nature of this genre of language activity, whose principal aim is opinion leadership and of the audience that is highly heterogenous but at the same time capable of detecting and processing sophisticated logical and rhetorical devices. That imposes some structural conditions besides general structure specialties of the Japanese language.

A multi-layer ML model evolutionary paradigm for high-accuracy individual aircraft SHM

Evolutionary Machine Learning (EML) has emerged as a novel direction for providing robust methodologies for effectively tackling complex problems. However, most current research focuses on multi-objective optimization problems in machine learning (ML). There is limited research on the EML mechanism along the temporal application process, where a fixed machine learning model trained with the prior dataset will inevitably be not representative of the target problem with time. Taking the Structural Health Monitoring (SHM)-ML damage diagnosis model as an example, this paper proposes a novel multi-layer ML model evolutionary paradigm with multi-source data for high-accuracy individual aircraft SHM. The proposed paradigm considers three interconnected layers for the SHM-ML damage diagnosis model, including the dataset to establish the diagnosis model, the model structure and its parameter training, and mapping relationship used in the model to give the damage size. Besides, for a specific model of aircraft, there exist multiple stages from design to service, where multi-source of data is fused for the multi-layer evolution, enabling continuous improvement of damage diagnosis accuracy. Experimental validation is conducted on critical connection structures of aircraft, specifically the attachment lug structure, using the active guided wave SHM method. The results demonstrate the effectiveness of the proposed multi-layer ML model evolutionary paradigm.

Optical–electrical simulation and optimization of an efficient lead-free 2T all perovskite tandem solar cell

The characteristics of a lead-free all perovskite tandem solar cell (P-TSC) are studied in this study. All P-TSCs were developed with the goal of breaking through the theoretical power conversion efficiency (PCE) limit for single-junction (SJ) perovskite solar cells (PSCs) established by Shockley and Queisser. Solving the toxicity problem in lead-containing sub-cells is essential for the continued growth of all P-TSCs. Here, we first present a coupled three-dimensional (3D) optical–electrical simulation of two lead-free SJ MAGeI3(Eg=1.9eV) and MASnI3(Eg=1.3eV) PSCs. The results showed that the PCE of the SJ-wide bandgap (WBG) and SJ-narrow bandgap (NBG) PSCs is 19.59% and 15.57%, respectively. Next, a two-terminal (2T) eco-friendly all P-TSC with combines these two solar cells has been designed, where the MAGeI3-PSC serves as the top sub-cell and the MASnI3-PSC serves as the bottom sub-cell. By establishing the current matching condition between two sub-cells in the 2T structure, the matched short-circuit current density (Jsc) and PCE are obtained 12.30mA/cm2 and 28.46%, respectively. Herein, a 299 nm-thick NBG-absorber layer and a 200 nm-thick WBG-absorber layer are required. In order to increase the matched Jsc and PCE and decrease the required NBG-absorber layer thickness, the parasitic absorption and reflection losses are minimized by selecting the best materials for the transparent conductive oxide (TCO) front contact and interconnecting (IC) layers, as well as the addition of an anti-reflection (AR) layer at the air/device interface as light management strategies. The results indicate that, under the current matching condition, improving the structure would lead to in a 76 nm reduction in the NBG-absorber layer’s required thickness and a 16.44% increase in PCE. Finally, we suggested the optimized 2T non-Pb all P-TSC with a high PCE of 33.14% that is environmentally safe.

Efficient All-Perovskite Tandem Solar Cells with Low-Optical-Loss Carbazolyl Interconnecting Layers.

Combining wide-band gap (WBG) and narrow-band gap (NBG) perovskites with interconnecting layers (ICLs) to construct monolithic all-perovskite tandem solar cell is an effective way to achieve high power conversion efficiency (PCE). However, optical losses from ICLs need to be further reduced to leverage the full potential of all-perovskite tandem solar cells. Here, metal oxide nanocrystal layers anchored with carbazolyl hole-selective-molecules (CHs), which exhibit much lower optical loss, is employed to replace poly(3,4-ethylenedioxythiophene) polystyrenesulfonate (PEDOT : PSS) as the hole transporting layers (HTLs) in lead-tin (Pb-Sn) perovskite sub-cells and ICLs in all-perovskite tandem solar cells. Optically transparent indium tin oxide nanocrystals (ITO NCs) layers are employed to enhance anchoring of CHs, while a mixture of two CHs is adopted to tune the surface energy-levels of ITO NCs. The optimized mixed Pb-Sn NBG perovskite solar cells demonstrate a high PCE of 23.2 %, with a high short-circuit current density (Jsc ) of 33.5 mA cm-2 . A high PCE of 28.1 % is further obtained in all-perovskite tandem solar cells, with the highest Jsc of 16.7 mA cm-2 to date. Encapsulated tandem solar cells maintain 90 % of their reference point after 500 h of operation at the maximum power point (MPP) under 1-Sun illumination.

Efficient All‐Perovskite Tandem Solar Cells with Low‐Optical‐Loss Carbazolyl Interconnecting Layers

AbstractCombining wide‐band gap (WBG) and narrow‐band gap (NBG) perovskites with interconnecting layers (ICLs) to construct monolithic all‐perovskite tandem solar cell is an effective way to achieve high power conversion efficiency (PCE). However, optical losses from ICLs need to be further reduced to leverage the full potential of all‐perovskite tandem solar cells. Here, metal oxide nanocrystal layers anchored with carbazolyl hole‐selective‐molecules (CHs), which exhibit much lower optical loss, is employed to replace poly(3,4‐ethylenedioxythiophene) polystyrenesulfonate (PEDOT : PSS) as the hole transporting layers (HTLs) in lead‐tin (Pb‐Sn) perovskite sub‐cells and ICLs in all‐perovskite tandem solar cells. Optically transparent indium tin oxide nanocrystals (ITO NCs) layers are employed to enhance anchoring of CHs, while a mixture of two CHs is adopted to tune the surface energy‐levels of ITO NCs. The optimized mixed Pb‐Sn NBG perovskite solar cells demonstrate a high PCE of 23.2 %, with a high short‐circuit current density (Jsc) of 33.5 mA cm−2. A high PCE of 28.1 % is further obtained in all‐perovskite tandem solar cells, with the highest Jsc of 16.7 mA cm−2 to date. Encapsulated tandem solar cells maintain 90 % of their reference point after 500 h of operation at the maximum power point (MPP) under 1‐Sun illumination.

ViT-DexiNet: a vision transformer-based edge detection operator for small object detection in SAR images

ABSTRACTThis paper introduces a novel edge detection operator called ‘vision transformer-based Dexinet (ViT-DexiNet)’ to address the challenges of detecting small objects in synthetic aperture radar (SAR) images. SAR images are typically impacted by strong multiplicative noise, making edge detection difficult. Existing traditional methods have limited spectral data preservation capabilities and often result in a loss of clarity and integrity of salient features in SAR images. The proposed ViT-DexiNet operator employs a series of interconnected layers to extract and refine salient edge features from SAR images. It utilizes a vision transformer self-attention layer to capture the pattern and structural details of image features crucial for determining edges. The extracted feature maps are then processed by the DexiNet architecture, which consists of a dense block, transfer block, and upsampling network. This architecture helps preserve edge information at different scales in deeper layers. The series of layered blocks generate edge maps, which are concatenated and averaged through smoothing to remove noise and enhance edge details in SAR images, resulting in a final high-quality edge map. To evaluate the proposed ViT-DexiNet method, both qualitative and quantitative analyses are conducted using standard edge detection operators such as Canny and Sobel. The empirical results demonstrate that the ViT-DexiNet surpasses baseline edge detection operators. The achieved values of proposed edge detection operator are 97.92%, 97.72%, 97.64% and 97.41%, respectively for the metrics accuracy, precision, recall and f1-score. The ViT-DexiNet offers high-quality edge maps, simplifying the interpretation of data for small object detection. Overall, the ViT-DexiNet method shows promise in overcoming the limitations of traditional approaches and improving the detection of edges in SAR images.

Decoupling the Trade‐Off Between the Photosignal and Photonoise in Upconversion Devices Through a Solution‐Processed Nickel Oxide Interconnecting Layer

AbstractNear‐infrared (NIR) to visible upconversion devices (UCDs) provide a viable and cost‐effective way for NIR visualization and pixel‐less imaging techniques. An excellent electrical connection between the NIR detection unit and the visible emission unit in the UCD is one of the prerequisites for achieving efficient upconversion performance. In this study, a low temperature‐ and solution‐processed nickel oxide (NiOx) interconnecting layer (ICL) with high hole mobility and favorable energy levels is demonstrated to decouple the trade‐off between photosignal and photonoise in the UCDs. The use of such a NiOx ICL suppresses intrinsic visible emission in the dark (photonoise) but enhances visible light output under NIR illumination (photosignal) by triggering an efficient charge injection in the UCDs. As a result, a hybrid UCD monolithically integrating an organic NIR photodetector and a visible quantum dot light‐emitting diode via the NiOx ICL achieves excellent performance, exhibiting an ultralow turn‐on voltage as low as 1.6 V, a high luminance close to 6.3 × 103 cd m−2, a wide operation voltage window up to 7.4 V, and a high contrast ratio reaching 5 × 104. The resulting UCD is also used for imaging demonstrations showing clear visible images of the NIR targets, which paves the way for practical applications.

High-throughput Printing of Micro and Nanoscale Interconnects, and Passive and Active Electronics Elements for Heterogeneous Integration and Advanced Packaging Applications

We introduce a new additive manufacturing technology for making electronics that is estimated to cost up to 100 times less than conventional semiconductor manufacturing. The technology significantly reduces the infrastructure and operating cost, power, water, chemical use, and reduces the materials used in fabrication by three orders of magnitude. This new technology enables allowing device designers the use of any organic or inorganic semiconducting, conductive, or insulating material on flexible or rigid substrates. The new technology is enabled by directed assembly-based nanoscale printing at room temperature and pressure and can print 1000 faster and 1000 smaller (down to 25 nm) structures than inkjet-based printing. The nanoscale printing platform enables the heterogeneous integration of interconnected circuit layers, printed electronics (passive and active electronics components), and sensors on flexible or rigid substrates. The directed assembly-based printing processes were specifically created to be scalable, environmentally sustainable, and enable precise and repeatable control of the assembly of various nanomaterials at very high rates. This allows the printing of passive and active components monolithically on an interposer platform along with interconnects for redistribution layers such that the total footprint can be within a few mm of the original IC footprint. The new technology has demonstrated the printing of several devices including transistors, inverters, diodes, displays, chemical, and biosensors, and interconnects using a variety of nanomaterials at the nano and microscale.

Polyphony, sonic texture and acoustic ecology in Cynan Jones’s Stillicide

Polyphony, sonic texture and acoustic ecology in Cynan Jones’s <i>Stillicide</i>

High-density Fan-Out Chip on Substrate using M-Series (TM) and Adaptive Patterning® Technology

As silicon technology nodes advance and wafer costs increase, there is a strong incentive to shrink die size and concurrently, die pad pitch. This increased density typically drives higher cost advanced substrates with finer lines and spaces and potentially more layers. As a result of recent constraints on the substrate supply chain, this creates serious availability and cost concerns. A compelling solution is to use fan-out on substrate technology to increase the effective die pad pitch, allowing the use of simpler, lower layer count substrates. ASE used this single die Fan Out Chip on Substrate (FOCoS) approach in engineering and qualification builds starting in 2017 with a traditional fan-out solution. However, with increasing interconnect density, the conventional approach is limited in its ability to work with small bond pad pitches as the die shift during molding creates challenges for manufacturing. An oversized capture pad is often utilized to accommodate this shift and in one prominent case, an additional Cu layer is required. M-series’ use of Adaptive Patterning eliminates the need for oversized capture pads through a unique design-during-manufacturing process which precisely aligns the package interconnect layers to the actual location of each die after molding. This paper will examine the design and manufacturing of a FOCoS package using 4nm silicon through the cooperation of Deca and ASE. The design fans out the interface of a 12mm x 12mm die with 6,000 IO using a single RDL layer and 5 µm line and space. The die has a core pitch of 150µm with an average periphery pitch of 90µm. The resultant M-series flip-chip bumps have a core pitch of 150µm over 75% of the die area with a secondary pitch of 212µm encompassing the remaining perimeter of the die and the 30% body size growth provided by the fan-out region. The relaxed pitch provided by M-series fan-out opens the possibility to use the most cost-effective, readily available type of laminate substrate.

Assessment of Joinability in Additively Manufactured Interlocking Structures

This study investigates the challenges of additively manufactured interlocking structures, emphasizing joinability issues due to thermal deformation. These challenges become pronounced when fabricating high-density structures without fully interconnected layers, a trait common in soft magnetic materials. Here, a detailed analysis assessing deformation concerning pin thickness and build orientation in a representative interlocking model is performed. Utilizing stress and thermal simulations of the additive manufacturing process, it is shown that a compensated design considerably enhances the joinability of these structures. These findings offer valuable perspectives for advancing the design of additive manufacturing components, particularly in soft magnetic materials such as electric motor stators, which require both insulation and density.

Diamond hands to the moon: Idiocultural mobilization and politicization of personal finance on r/wallstreetbets

In January 2021, the shares of the brick-and-mortar video games retail chain GameStop exploded in value. At the same time, billboards on highways and ads in Times Square in New York City used cryptic visuals and seemingly meaningless emojis with diamonds and rockets. Mainstream media soon had an explanation: This was the story of how the subreddit r/wallstreetbets had mobilized thousands of retail investors in a fight against evil hedge funds. Based on a case study of r/wallstreetbets and the GameStop incident, we analyze how idiosyncratic internet culture was incorporated into a broadly resonant and emotionally inflected narrative that lionized the ‘little man’, focusing on both individual profits and collective grievances. Through a theoretical framework combining sociological theories of internet culture and framing analysis, we identify an overall communication structure that drew on three interconnected discursive layers: idiocultural memes, investment-specific information, and a moralized, collectivized injustice frame with heroes and villains. We further argue that the GameStop (GME) incident instantiates a case of the politicization of personal finance, where the investment practices and strategies of ordinary people were transformed into a political issue. As such, the article makes two contributions to the existing literature. First, we contribute to the nascent literature on internet cultures related to personal finance by looking at a specific subreddit devoted to stock trading and investing. Second, we show how idiocultural elements, such as emojis and memes, can function both as contested and exclusionary material aimed at insiders and as flexible components of communications framed for broad mobilization through emotionally resonant notions of grievance and injustice.

Deformation behavior of heterogeneous lamellar Cu-Fe-P immiscible alloys with enhanced strength and ductility produced by laser powder bed fusion

Cu-Fe-P immiscible alloys characterized by heterogeneous lamellar structure were manufactured by laser powder bed fusion (LPBF) and the deformation behavior of LPBF-produced immiscible alloys was investigated systematically. When the linear energy density of 133 J/m is adopted during LPBF, the immiscible alloy exhibits the highest compressive strength (∼1 GPa) and engineering strain (∼27%). The high strength of the LPBF-produced immiscible alloy is attributed to the heterogeneous lamellar structure including the interconnected Fe2P layer and nano-Fe2P particles as “hard” phase dispersed in the ε-Cu matrix as the “soft” phase. Moreover, the good ductility is attributed to the fine ε-Cu grains as “soft” phase precipitated within the lamellar Fe2P due to the secondary liquid phase separation (SLPS). This “soft-hard-soft” heterogeneous microstructure can effectively delay crack growth to exhibit excellent mechanical properties in the LPBF-produced immiscible alloys.

Carto-City to Surface-City: un-mapping and re-mapping the urban emotion of missing

ABSTRACT Drawing on a fascination with Denis Cosgrove’s term ‘Carto-City’ that encompasses the concept that ‘Urban space and cartographic space are inseparable’ [Cosgrove, D. (2006). Carto-City. In J. Abrams, & P. Hall (Eds.), Else/where: Mapping New cartographies of networks and territories (pp. 148–157). University of Minnesota], this essay applies the idea to a conceptualisation of ‘city’ as urbaness – as a connected state of mind or urban emotion. Through a visual methodology of ‘unmapping’ and ‘re-mapping’ of Carto-City as Surface-City, this artistic research practice aims to contribute to how we understand and map the connected cartographies of contemporary urban consciousness. Cosgroves “seeing, imagining and representing” (2008) is re-interpreted to map a specific emotion within urbaness emerging out of the restricted transience of a world-wide pandemic – the emotion of missing. As physical city spaces across the world stood still, digital connection expanded creating a focused space for critical reflection on how interconnected layers of urban emotion might be mapped. My response to this, Surface-City, is grounded in my ongoing body of research into urban consciousness and its mapping through academic writing and visual practice.

Process and Design Challenges for Hybrid Bonding

Achieving high-quality interconnect interfaces for fine pitch integration is crucial in today's advanced electronic systems. Among various interconnect options, hybrid bonding stands out as a superior choice due to its ability to accommodate a high input/output (I/O) count, enabling high-density memory integration, increased power delivery, and improved signal speed. To ensure the utmost quality in hybrid bonding, embedding Cu interconnects within the dielectric layer has proven effective. Furthermore, the surface planarization process, accomplished through chemical mechanical polishing (CMP), plays a pivotal role. In this regard, the final CMP process typically involves a meticulous two-step procedure involving copper bulk CMP followed by barrier CMP. The latter yields the desired surface finish crucial for successful hybrid bonding. Several key surface properties, including copper recess (referred to as dishing) in the vias, erosion and roughness of the dielectric layer, and surface topography changes from high-density to low-density copper vias, significantly impact the overall bond yield. To optimize these parameters, a comprehensive understanding of the design of the interconnect layer for the CMP process is essential. In this study, we explore the impact of via scaling and via density for interconnect pitches from 5 μm to 1 μm and the surface topography due to dummy vias of the final bonding surface.