Interconnects In Circuits Research Articles

EXTH-61. TOWARDS A QUANTUM THERAPY FOR GLIOBLASTOMA: A NEW THERAPEUTIC PARADIGM IN MEDICINE

Abstract BACKGROUND A cell operates as an interconnected bioelectrical circuit, utilising electron transfer processes for intracellular communication, with cytochrome c (Cyt c) playing a pivotal role. The redox processes of Cyt c, occurring via electron tunnelling, are essential for its translocation into the cytosol and modulation of its conformation to bind apoptotic protease activating factor 1. This highlights the need for novel technologies capable of interacting with these processes at the atomic scale to control downstream effects and induce apoptosis in cancer cells. METHODS We demonstrate that ‘bio-nanoantennae’, when supplied with an electrical current, enable quantum biological tunnelling for electron transfer (QBET) and facilitate cellular apoptosis in patient-derived IDH wild-type glioblastoma from both the infiltrative tumour margin and proliferative core. The bio-nanoantennae were constructed from gold nanoparticles functionalised with reduced Cyt c and zinc porphyrin as a redox couple. RESULTS Electrical polarisation of these bio-nanoantennae via resonant alternating currents in preclinical glioblastoma cells led to decreased metabolic activity and reduced cell viability by oxidizing Cyt c, thus inducing cellular stress. No significant effect was observed in healthy human astrocyte counterparts. The cytosol localised bio-nanoantennae induced differential gene expression related to ion channels, apoptosis, cancer proliferation and tumour suppression upon activation, in tumour relative to astrocyte cell populations. The bio-nanoantennae were also tested in 3D glioblastoma spheroid models, showing similar effects, and in vivo studies demonstrated a significant reduction in glioblastoma xenograft tumour size. CONCLUSION We propose that bio-nanoantennae modulate the redox state of Cyt c under an electrical field through QBET. To validate this, we investigated the tunnel junction energy and plasmon resonance scattering, and developed a mathematical model to explain the system’s behaviour. This innovative wireless electrical–molecular nanodevice, capable of inducing cancer cell apoptosis, paves the way for further applications of quantum signalling as a new (non-pharmacological) therapeutic paradigm.

Pressure-constrained sonication activation of flexible printed metal circuit

Metal micro/nanoparticle ink-based printed circuits have shown promise for promoting the scalable application of flexible electronics due to enabling superhigh metallic conductivity with cost-effective mass production. However, it is challenging to activate printed metal-particle patterns to approach the intrinsic conductivity without damaging the flexible substrate, especially for high melting-point metals. Here, we report a pressure-constrained sonication activation (PCSA) method of the printed flexible circuits for more than dozens of metal (covering melting points from room temperature to 3422 °C) and even nonmetallic inks, which is integrated with the large-scale roll-to-roll process. The PCSA-induced synergistic heat-softening and vibration-bonding effect of particles can enable multilayer circuit interconnection and join electronic components onto printed circuits without solder within 1 s at room temperature. We demonstrate PCSA-based applications of 3D flexible origami electronics, erasable and foldable double-sided electroluminescent displays, and custom-designed and large-area electronic textiles, thus indicating its potential for universality in flexible electronics.

On chip control and detection of complex SPP and waveguide modes based on plasmonic interconnect circuits

Abstract Optical interconnects, leveraging surface plasmon modes, are revolutionizing high-performance computing and AI, overcoming the limitations of electrical interconnects in speed, energy efficiency, and miniaturization. These nanoscale photonic circuits integrate on-chip light manipulation and signal conversion, marking significant advancements in optoelectronics and data processing efficiency. Here, we present a novel plasmonic interconnect circuit, by introducing refractive index matching layer, the device supports both pure SPP and different hybrid modes, allowing selective excitation and transmission based on light wavelength and polarization, followed by photocurrent conversion. We optimized the coupling gratings to fine-tune transmission modes around specific near-infrared wavelengths for effective electrical detection. Simulation results align with experimental data, confirming the device’s ability to detect complex optical modes. This advancement broadens the applications of plasmonic interconnects in high-speed, compact optoelectronic and sensor technologies, enabling more versatile nanoscale optical signal processing and transmission.

Electromigration Analysis for Interconnects Using Improved Graph Convolutional Network with Edge Feature Aggregation.

Electromigration (EM) is a critical reliability issue in integrated circuits and is becoming increasingly significant as fabrication technology nodes continue to advance. The analysis of the hydrostatic stress, which is paramount in electromigration studies, typically involves solving complex physical equations (partial differential equations, or PDEs in this case), which is time consuming, inefficient and not practical for full-chip EM analysis. In this paper, a novel approach is proposed, conceptualizing circuit interconnect trees as a graph within a graph neural network framework. Using finite element solution software, ground truth hydrostatic stress values were obtained to construct a dataset of interconnected trees with hydrostatic stress values for each node. An improved Graph Convolutional Network (GCN) augmented with edge feature aggregation and attention mechanism was then trained employing the dataset, yielding a model capable of predicting hydrostatic stress values for nodes in an interconnect tree. The results show that our model demonstrated a 15% improvement in the Root Mean Square Error (RMSE) compared to the original GCN model and improved the solution speed greatly compared to traditional finite element software.

An ultra-short-acting benzodiazepine in thalamic nucleus reuniens undermines fear extinction via intermediation of hippocamposeptal circuits

Benzodiazepines, commonly used for anxiolytics, hinder conditioned fear extinction, and the underlying circuit mechanisms are unclear. Utilizing remimazolam, an ultra-short-acting benzodiazepine, here we reveal its impact on the thalamic nucleus reuniens (RE) and interconnected hippocamposeptal circuits during fear extinction. Systemic or RE-specific administration of remimazolam impedes fear extinction by reducing RE activation through A type GABA receptors. Remimazolam enhances long-range GABAergic inhibition from lateral septum (LS) to RE, underlying the compromised fear extinction. RE projects to ventral hippocampus (vHPC), which in turn sends projections characterized by feed-forward inhibition to the GABAergic neurons of the LS. This is coupled with long-range GABAergic projections from the LS to RE, collectively constituting an overall positive feedback circuit construct that promotes fear extinction. RE-specific remimazolam negates the facilitation of fear extinction by disrupting this circuit. Thus, remimazolam in RE disrupts fear extinction caused by hippocamposeptal intermediation, offering mechanistic insights for the dilemma of combining anxiolytics with extinction-based exposure therapy.

Purifying High-Purity Copper via Semi-Continuous Directional Solidification: Insights from Numerical Simulations

High-purity copper is essential for fabricating advanced microelectronic devices, particularly integrated circuit interconnects. As the industry increasingly emphasizes scalable and efficient purification methods, this study investigates the multi-physics interactions during the semi-continuous directional solidification process, utilizing a Cu-1 wt.%Ag model alloy. Coupled simulation calculations examine the spatial distribution patterns of the impurity element silver (Ag) within semi-continuously solidified ingots under varying pulling rates and melt temperatures. The objective is to provide technical insights into the utilization of the semi-continuous directional solidification method for high-purity copper purification. The findings reveal that increasing the pulling rate and melt temperature leads to a downward shift in the solid–liquid interface relative to the mold top during processing. Alongside the primary clockwise vortex flow, a secondary weak vortex emerges near the solid–liquid interface, facilitating the migration of the impurity element Ag toward the central axis and amplifying radial impurity fluctuations. Furthermore, diverse pulling rates and melt temperature conditions unveil a consistent trend along the ingot’s height, which is characterized by an initial increase in average Ag content, followed by stabilization and then a rapid ascent during the late stage of solidification, with higher pulling rates and melt temperatures expediting this rapid ascent. Leveraging these insights, a validation experiment using 4N-grade recycled copper in a small-scale setup demonstrates the effectiveness of the semi-continuous directional solidification process for high-purity copper production, with copper samples extracted at 1/4 and 3/4 ingot heights achieving a 5N purity level of 99.9994 wt.% and 99.9993 wt.%, respectively.

The neurotransmitters of sleep and arousal

The sleep and arousal, or the vigilance state, is controlled by a highly dynamic brain system that involves numerous interconnected brain circuits. However, while many reviews presented the anatomical bases of how different components of the brain area contribute to the vigilance states, less attention is paid from the perspective of different neurotransmitters. As multiple different neuronal populations could exist and express in the same brain area, attributing the effect of different brain areas on sleep and arousal would not be precise without consideration of the act of neurotransmitters. This review summarizes the recent progress on how different neurotransmitters affect vigilance states. By doing so, this review aims to provide an alternative angle in understanding how different vigilance state is regulated by the brain.

Global RC Interconnects with ADL Buffers for Low-Power Applications

Introduction: Interconnects are an essential requirement for any circuit completion. They are utilised to connect two or more blocks, yet when creating a circuit, certain problems have been observed. Scaling back technology is one such problem. Methods: With technology scaled down their aspects change which can straightforwardly affect the circuit boundaries. Because of this, the time constant and power consumption in the interconnect circuits has increased. Certain wire (RC) models and techniques have previously been characterized to control these performance parameters however in this paper, authors have proposed a new interconnect structure with a buffer insertion technique using adiabatic dynamic logic (ADL). Results: To optimise power, a Schmitt trigger is inserted as a buffer between lengthy interconnect circuits utilising an energy-recovery mechanism. The TSPICE tool is used to model and simulate the entire circuit. Conclusion: The suggested model's performance is compared to that of other cutting-edge methods.

Study on reliability of gold belt welding for Aerospace Microwave Circuit

As a highly reliable and flexible interconnection method, gold belt welding is widely used in the interconnection of aerospace microwave circuits. In this paper, to reveal the influence of the technological parameters of gold belt welding on stress, the typical aerospace electronic equipment was studied by Ansys finite element software. The result shows that the stiffness consistency of two structures which are connected by a gold belt and the winding radius of the gold belt are the crucial factors in the reliability of gold belt connection. A process-strengthening measure has been proposed based on the analysis results. The verification of the process experiment shows that using EC2216 adhesive on both sides of a gold belt can effectively reduce stress and improve mechanical reliability. Furthermore, the analytical methods and measures have been extended to other flexible interconnection methods, which provide a solution to the highly reliable interconnection in the aerospace product.

Design of Global RLC Interconnect Circuit with Analytical Delay Model

Background: With the advancement in technology nodes and scaling trends, the majority of the device performance depends upon the interconnections made between two or more devices. With these scaling trends, frequency plays a vital role. As the technology decreases, frequency tends to rise to giga-hertz. This increase in frequency gives rise to inductance parameters in the interconnect circuits. For long wires, the inductive impedance can become comparable to the resistive component due to which performance degradation can be observed along with overshoot and crosstalk issues that can no longer be ignored. Method: This article aims to examine the delay model and reconstruct an interconnect circuit that serves as a transmission line, ranging in length from 1 mm to 10 mm. Result: By keeping the frequency high, low voltage and rise/ fall time, performance parameters such as delay, power consumption, and overshoot are observed. Conclusion: The interconnect structure is compared with another state-of-the-art technique.

The Relative Contribution of Glycine-GABA Cotransmission in the Core of the Respiratory Network.

The preBötzinger complex (preBötC) and the Bötzinger complex (BötC) are interconnected neural circuits that are involved in the regulation of breathing in mammals. Fast inhibitory neurotransmission is known to play an important role in the interaction of these two regions. Moreover, the corelease of glycine and GABA has been described in the respiratory network, but the contribution of the individual neurotransmitter in different pathways remains elusive. In sagittal brainstem slices of neonatal mice, we employed a laser point illumination system to activate glycinergic neurons expressing channelrhodopsin-2 (ChR2). This approach allowed us to discern the contribution of glycine and GABA to postsynaptic currents of individual whole-cell clamped neurons in the preBötC and BötC through the application of glycine and GABA receptor-specific antagonists. In more than 90% of the recordings, both transmitters contributed to the evoked IPSCs, with the glycinergic component being larger than the GABAergic component. The GABAergic component appeared to be most prominent when stimulation and recording were both performed within the preBötC. Taken together, our data suggest that GABA-glycine cotransmission is the default mode in the respiratory network of neonatal mice with regional differences that may be important in tuning the network activity.

Space-Confined Growth of Ultrathin P-Type GeTe Nanosheets for Broadband Photodetectors.

As p-type phase-change degenerate semiconductors, crystalline and amorphous germanium telluride (GeTe) exhibit metallic and semiconducting properties, respectively. However, the massive structural defects and strong interface scattering in amorphous GeTe films significantly reduce their performance. In this work, two-dimensional (2D) p-type GeTe nanosheets are synthesized via a specially designed space-confined chemical vapor deposition (CVD) method, with the thickness of the GeTe nanosheets reduced to 1.9nm. The space-confined CVD method improves the crystallinity of ultrathin GeTe by lowering the partial pressure of the reactant gas, resulting in GeTe nanosheets with excellent p-type semiconductor properties, such as a satisfactory on/off ratio of 105. Temperature-dependent electrical measurements demonstrate that variable-range hopping and optical-phonon-assisted hopping mechanisms dominate transport behavior at low and high temperatures, respectively. GeTe devices exhibit significantly high responsivity (6589 and 2.2 A W-1 at 633 and 980nm, respectively) and detectivity (1.67 × 1011 and 1.3 × 108 Jones at 633 and 980nm, respectively), making them feasible for broadband photodetectors in the visible to near-infrared range. Furthermore, the fabricated GeTe/WS2 diode exhibits a rectification ratio of 103 at zero gate voltage. These satisfactory p-type semiconductor properties demonstrate that ultrathin GeTe exhibits enormous potential for applications in optoelectronic interconnection circuits.

Energy Optimization for RC and RLC Interconnect Design in Low Power VLSI

Background: The global RC interconnects have become the controlling parameter for a circuit’s performance. But with the decrease in technology, an increase in resistance has become prominent. This increase further directly affects the performance of the system by increasing the performance parameters of the circuit like delay and power consumption. To resolve this issue and to be compatible with Internet of Things (IoT) applications, the interconnect circuits are required to be high speed with less heat generation. Methods: In this paper, a new RC and RLC interconnect circuit design was proposed for 45 nm technology to enhance the performance parameters. Furthermore, the RC interconnect design was simulated for lumped and distributed networks. The parasitic component values (resistance, inductance, and capacitance) are evaluated using PTM technology. Results: The proposed interconnect circuit's resistance value decreased by a factor of 4, but the capacitance remains the same. Furthermore, power consumption and delay values were attained. An overall comparison was done between RC and RLC networks. Conclusion: 63.13% power improvement and 24.87% delay improvement were observed in the RLC network over RC distributed network.

Tailoring group delay dispersion of surface plasmon polaritons propagating on thin gold film by chirped femtosecond laser pulses

Understanding the propagation characteristics of surface plasmon polaritons (SPPs) is of great significance in designing and constructing on-chip integrated systems utilizing plasmonic effect. Accurately characterizing and flexibly controlling SPP on thin metal film are indispensable. Here, we theoretically derive the group velocity dispersion of SPP propagation on the surface of Au films with various thicknesses. The results obtained in this work indicate that when the thickness of the Au film is less than 40 nm, group velocity dispersion of SPP decreases significantly as the film thickness increases. The decrease of group velocity dispersion becomes mild with the thickness increasing from 40 nm to 60 nm, then the dispersion keeps a very low constant value for the film thicker than 60 nm. Using the finite-difference time-domain method, temporal evolution of localized electric field of SPP is numerically simulated for various propagation distances. By comparing the field amplitudes and the dispersions of SPP which are excited by incident light pulses with different dispersions, group velocity dispersions of SPP on the Au films are obtained, showing a good consistence with the theoretical results. Moreover, we demonstrate that by utilizing the tailored SPP to excite metal nanoantenna, selective excitations at different frequencies on a femtosecond temporal scale can be achieved through localized surface plasmonic resonant effect. Manipulating the sign and amount of the dispersion from the incident pulse, the active control of the switching sequence and switching time of electric field between the Au cylinders can be achieved. Manipulating the propagation distance of SPP, the active control of the switching time of electric field between the Au cylinders can be achieved. Therefore, those results provide a promising avenue for realizing functions such as signal propagation, reception, adjustment, and encoding in on-chip interconnect circuit systems based on SPP. This work shows that the dispersion can be used as degree of freedom for controlling the amplitude, phase and pulse width of SPP propagating on thin film, and it is of great importance in designing and controlling on-chip integrated systems through utilizing plasmonic effect, such as ultrafast frequency demodulators and nanoantennas in on-chip interconnect optical circuits.

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.

Arbitrary orthogonal polarization-dependent directional launching of Bessel-like surface plasmon polariton beams

Nondiffracting Bessel-like SPP beams, with the unique features of effectively suppressing the diffraction of the beam, have great application prospects in the fields of on-chip interconnection circuit, optical tweezers, and micromanipulation. In practical applications, active manipulation of nondiffracting Bessel-like SPP beams is essential. Here, we proposed two kinds of nondiffracting Bessel-like SPP beam unidirectional devices controlled by arbitrarily orthogonally polarized incidence light, which can generate and manipulate zeroth-order or first-order Bessel-like SPP beams, respectively. The results show that, by changing the distance between two pairs of slit couplers with different resonance responses, the nondiffracting Bessel-like SPP beams can be directionally excited at arbitrarily polarized incidence, and the excitation direction of the nondiffracting Bessel-like SPP beams will reverse under the corresponding orthogonally polarized incidence. The proposed devices provide promising opportunities for constructing polarization-based dynamic manipulation plasmonic devices of nondiffracting SPP beams and have potential applications in on-chip interconnection circuits.

Ruthenium electrodeposition from non-aqueous electrolytes containing divalent ions

The electrodeposition of ruthenium from an ethylene glycol based electrolyte containing the metal in its divalent state is investigated for the first time. Ascorbic acid is used to reduce a fraction of the Ru(III) ions added to the non-aqueous solvent to Ru(II). Its effect is studied by means of UV–visible spectroscopy and cyclic voltammetry, demonstrating the presence of divalent ions and the stability of the electrolyte over time. Ruthenium coatings are deposited on gold-sputtered silicon wafers under galvanostatic conditions at various current densities and deposition times. The characterizations carried out evidence the significant purity of the ruthenium film, while the morphological analysis reveals its compact and crack-free morphology. Indeed, thicknesses up to 2.35 µm are successfully plated with no sign of delamination or cracking. The good electrical properties observed for the deposited layers validate the possible applicability of the Ru(II) containing non-aqueous electrolyte here described to the manufacturing of integrated circuits interconnects or contacts for electrical applications.

Executive functions, self-regulation and social media for peace-based inclusive education

This article comprehensively explores the critical interplay between executive functions (EFs), self-regulation, and social media in promoting a peaceful and inclusive educational environment. The study emphasizes the significance of EFs in regulating cognitive processes and coping with new challenges, focusing on the prefrontal cortex (PFC) and its interconnected neural circuits. Addressing the relevance of EFs in conflict resolution, emotional regulation, and metacognitive practices, the research investigates how they contribute to constructive conflict-resolution, emotional maturity, and responsible online behavior in educational settings. Furthermore, the bidirectional relationship between prosocial behaviors and EFs is explored, revealing their mutual reinforcement during early childhood and beyond. The article discusses the benefits and challenges of social media in educational contexts, highlighting the importance of mindful usage to promote positive interactions and empathy among students, educators, and stakeholders. Adopting a holistic approach, the study examines successful self-regulation practices and approaches that empower individuals to navigate negative emotions and cultivate positive relationships within groups. Additionally, the review sheds light on the potential implications of EFs and self-regulation in neurodevelopmental disorders, such as autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD). It identifies shared genetic bases and neurobiological underpinnings, offering valuable insights for developing targeted interventions to enhance executive function skills in affected populations. The findings have practical implications for professionals in education, parents, and policymakers, emphasizing the importance of nurturing emotional regulation, promoting metacognitive practices, and ensuring responsible social media use to create a harmonious and inclusive educational environment. The article aims to provide valuable insights for researchers and practitioners seeking to cultivate empathy, support positive conflict resolution, and facilitate the holistic development of students and stakeholders in educational and intimate learning environments.

Obesity wars: hypothalamic sEVs a new hope.

There are currently several pharmacological therapies available for the treatment of obesity, targeting both the central nervous system (CNS) and peripheral tissues. In recent years, small extracellular vesicles (sEVs) have been shown to be involved in many pathophysiological conditions. Because of their special nanosized structure and contents, sEVs can activate receptors and trigger intracellular pathways in recipient cells. Notably, in addition to transferring molecules between cells, sEVs can also alter their phenotypic characteristics. The purpose of this review is to discuss how sEVs can be used as a CNS-targeted strategy for treating obesity. Furthermore, we will evaluate current findings, such as the sEV-mediated targeting of hypothalamic AMP-activated protein kinase (AMPK), and discuss how they can be translated into clinical application.

Self-Powered UV Photodetector of TiO2 with BaTiO3 Surface Modification and Light-Controlled Logic Circuits Application.

One-dimensional (1D) metal oxides with excellent carrier transport and light absorption properties can be applied to photodetectors (PDs), facilitating device miniaturization, portability, and integration. Surface modification of 1D semiconductors can reduce carrier recombination in PDs as a way to increase photocurrent and decrease dark current of PDs. Herein, ultrathin BaTiO3 (BTO) shell layers are grown on the surface of TiO2 nanorod arrays (NRs) by in situ conversion using hydrothermal reaction, and the self-powered TiO2-BTO NRs PDs are constructed. The effect of the thickness of BTO shell layers on the photoresponse characteristics of self-powered TiO2-BTO NRs PDs is investigated by controlling the Ba2+ conversion concentration. The results show that the BTO shell layer reduces the dark current of the PDs because of the decreased interfacial transfer resistance and improved transfer of photogenerated carriers for building a "bridge" of carrier transport between BTO and TiO2 due to the formation of Ti-O-Ti bonds. Moreover, the presence of the spontaneous polarization electric field in BTO enhances the photocurrent and response speed of PDs. The self-powered TiO2-BTO NRs PDs are integrated in series and parallel to realize the functions of "and" and "or" gates of light-controlled logic gates. The ability to convert light signals into electrical signals for the self-powered PDs in real time demonstrates its great potential for optoelectronic interconnection circuits, which has important application prospects in the field of optical communication.