Metal Bond Research Articles

Experimental determination of electrophoretic deposition parameters and electrical characterization for K 0.5 Na 0.5 NbO3 perovskite thick films for energy harvesting applications

Globally, depleting non-renewable energy resources and environmental pollution are significant challenges. Much research is ongoing on perovskite coatings as a potential replacement. In this work, potassium sodium niobate (KNN) ceramics are fabricated by solid-state method, calcined at ∼850 °C, and electrophoreticcally deposited (EPD) on Ni-substrate uniquely then, sintered at high temperatures ∼1070–1120 °C. The X-ray diffraction and FTIR confirmed the development of a pure KNN perovskite structure and metallic bond groups (-O-Nb-O) present respectively. An increase in the sintering temperature resulted in the pronounced peaks observed in KNN ceramics, confirmed by Raman spectroscopy, and easily observed in SEM having “square” and “circular” morphology with grain growth. The coating thickness was measured around 18–116 μm and increasing deposition rate (0.084–0.337 μm/s) was calculated. The coating roughness (∼813 nm) was confirmed by atomic force microscopy. Complex impedance spectroscopic (CIS) analysis confirmed the high dielectric constant (∼4789) with a high transformation and curie temperature (TO→T ∼ 280 °C & TC ∼ 480 °C), respectively. The increasing conductivity (≥830 μS/m) at higher frequency and temperatures agree with the hopping conduction mechanism which confirmed the negative temperature coefficient of resistance (NTCR). The work holds great significance in sensors, actuators, spintronics, and energy harvesting applications.

АНАЛИЗ МЕТОДОВ ПРАВКИ КОЛЬЦЕВЫХ АЛМАЗНЫХ СВЕРЛ НА МЕТАЛЛИЧЕСКОЙ СВЯЗКЕ

The study objective is to analyze the existing methods to dress annular diamond drills of metal bonds and to develop new schemes of dressing used for diamond grinding tools.
 The paper is devoted to solving the problem, which consists in comparing different dressing methods, analyzing their disadvantages and advantages.
 Research methods are theoretical studies of various methods of annular diamond drill dressing.
 Novelty of the work: schemes for dressing annular diamond drills of metal bonds with free abrasive are developed.
 Research results: the existing methods and schemes for dressing annular diamond drills of metal bonds are analyzed, their main disadvantages and advantages are found. Dressing schemes for the free abrasive method are developed.
 Conclusions: when drilling hard non-metallic materials with annular diamond drills, the tool loses its functionality, glares and needs forced dressing. During the analysis, existing methods and possible dressing options are considered.

Boosted Light Alkane Deep Oxidation via Metal Bond Length Modulation-Induced C-C Bond Preferential Activation.

Light alkanes (LAs), typical VOCs existing in both stationary and mobile sources, pose significant environmental concerns. Although noble metal catalysts demonstrate strong C-H bond activation, their effectiveness in degrading LAs is hindered by inherent challenges, including poor chemical stability and water resistance. Here, from a new perspective, we propose a feasible strategy that adjusting the metal bond lengths within Pd clusters through partial substitution of smaller radius 3d transition metals (3dTMs) to prioritize the activation of low-energy C-C bonds within LAs. Benefiting from this, PdCo/CeO2 exhibits exceptional catalytic performance in propane degradation due to their high capacity for C-C cleavage stemming from the shorter Pd-Co length (2.51 Å) and lower coordination number (1.73), boosting the activation of α-H and β-H of propane simultaneously and accelerating the mobility of postactivated oxygen species to prevent Pd center deep oxidation. The presence of 3dTMs on Pd clusters improves the redox and charge transfer ability of catalysts, resulting in an amplified generation of oxygen vacancies and facilitating the adsorption and activation of reactants. Mechanistic studies and DFT calculations suggest that the substitution of 3dTMs significantly accelerate C-C bond cleavage within C3 intermediates to generate the subsequent C2 and C1 intermediates, suppressing the generation of harmful byproducts.

Potassium ion doped manganese oxide nanoscrolls enhanced the performance of aqueous zinc-ion batteries

α-MnO2 is a potential positive electrode material for aqueous zinc-ion batteries, but its electrochemical performance of zinc storage requires further improvement. In this paper, potassium ion-doped manganese dioxide nanoscrolls (KMnO2) with oxygen vacancy were synthesized by a one-step hydrothermal method. It was observed that the electrochemical specific capacity was 250.9 mAh/g at a current density of 0.2 C, which was better than the existing commercial α-MnO2. At a high current of 1 C, these batteries demonstrate improved cycle stability. Synchrotron radiation and other experiments as well as DFT theoretical calculations provided additional evidence that K doping was efficient in regulating the metal bond type and the mean charge regulation of covalent bonds with oxygen atoms in MnO2. When MnO and MnK bonds are present, KMnO2 showed outstanding adsorption of Zn2+ and further enhanced the Zn2+ embedding process. Simultaneously, oxygen defects caused by doping boosted the development of the nanoscroll structure, leading to an increase in active sites available for electrochemical reactions and subsequently enhancing the electrical conductivity of α-MnO2. This study exhibits the potential of optimizing materials based on manganese with the introduction of a potassium doping strategy, resulting in improved performance for aquatic zinc-ion batteries, and presents novel perspectives for related research.

Performance study of phosphate removal from water using synergistic interaction between lanthanum-magnesium bimetallic organic frameworks and polyethyleneimine

Aiming at the water solubility of Mg-MOFs and the problems of unstable adsorption performance and low life of pure MOFs caused by metal leakage, lanthanum and polyethyleneimine co-doped Mg-MOFs (2.0LMBP-2.5) were synthesized by solvothermal and impregnation methods. 2.0LMBP-2.5 not only has strong resistance for co-existing anions and acid-base, but also has excellent reusability and stability. Its maximum phosphate adsorption capacity was 514.15 mg·g−1. The phosphate removal rate reached 90.53 %-96.04 % in the pH range of 3.0–11.0. The results of kinetic, isothermal adsorption and thermodynamics showed that the phosphate adsorption process of 2.0LMBP-2.5 was a spontaneous heat absorption process and dominated by monolayer adsorption and chemisorption. FT-IR spectroscopy and XPS revealed a synergistic mechanism between MOFs and polyethyleneimine. The introduction of lanthanum improved the coordination metal bond strength of Mg-MOFs, effectively overcame the water solubility problem of Mg-MOFs. The introduction of lanthanum and polyethyleneimine significantly increased the adsorption capacity of Mg-MOFs, from 21.79 to 273.61 mg·g−1 and 273.61 to 514.15 mg·g−1, respectively.

Effect of Different Metal Bonding Agents on Shear Bond Strength of Ceramic to Direct Metal Laser Sintering

Introduction: laser sinter Cobalt Chromium metal replacing traditional casting processes of dental alloys for metal ceramic restorations, appropriate bonding of ceramic to metal is an important factor for long survival time. Twenty laser sinter cubic metal 10 mm for each sides was fabricated by software designing and CAD\CAM direct metal laser sintering technique. The twenty cubics were classified according to the type of metal to ceramic bonding agents into two groups (n=10), Ceram bond apply for group A and Crea alloy bond for group B. Samples fabricated using custom made silicon index was used to act as standardized mold for metal bond application and porcelain buildup. Instron with chisel indenter and special holding device were involve to measure the strength of bond for ceramic to laser sinter metal. The mean shear bond load of group A (688.8N) was significantly higher than that of group B (303.2N). Application of Ceram bond to metal laser sinter produces more bond strength when compare to usage of Crea bond material.

Stability and Electronic Properties of Mixed Rare-Earth Tri-Metallofullerenes YxDy3-x@C80 (x = 1 or 2).

Tri-metallofullerenes, specifically M3@C80 where M denotes rare-earth metal elements, are molecules that possess intriguing magnetic properties. Typically, only one metal element is involved in a given tri-metallofullerene molecule. However, mixed tri-metallofullerenes, denoted as M1xM23-x@C80 (x = 1 or 2, M1 and M2 denote different metal elements), have not been previously discovered. The investigation of such mixed tri-metallofullerenes is of interest due to the potential introduction of distinct properties resulting from the interaction between different metal atoms. This paper presents the preparation and theoretical analysis of mixed rare-earth tri-metallofullerenes, specifically YxDy3-x@C80 (x = 1 or 2). Through chemical oxidation of the arc-discharge produced soot, the formation of tri-metallofullerene cations, namely Y2Dy@C80+ and YDy2@C80+, has been observed. Density functional theory (DFT) calculations have revealed that the tri-metallofullerenes YxDy3-x@C80 (x = 1 or 2) exhibit a low oxidation potential, significantly lower than other fullerenes such as C60 and C70. This low oxidation potential can be attributed to the relatively high energy level of a singly occupied orbital. Additionally, the oxidized species demonstrate a large HOMO-LUMO gap similar to that of YxDy3-xN@C80, underscoring their high chemical stability. Theoretical investigations have uncovered the presence of a three-center two-electron metal-metal bond at the center of Y2DY@C80+ and YDy2@C80+. This unique multi-center bond assists in alleviating the electrostatic repulsion between the metal ions, thereby contributing to the overall stability of the cations. These mixed rare-earth tri-metallofullerenes hold promise as potential candidates for single-molecule magnets.

The Effect of Nb Doping on the Properties of Ti-Al Intermetallic Compounds Using First-Principles Calculations.

The crystal structures, stability, mechanical properties and electronic structures of Nb-free and Nb-doped Ti-Al intermetallic compounds were investigated via first-principles calculations. Seven components and eleven crystal configurations were considered based on the phase diagram. The calculated results demonstrate that hP8-Ti3Al, tP4-TiAl, tP32-Ti3Al5, tI24-TiAl2, tI16-Ti5Al11, tI24-Ti2Al5, and tI32-TiAl3 are the most stable phases. Mechanical properties were estimated with the calculated elastic constants, as well as the bulk modulus, shear modulus, Young's modulus, Poisson's ratio and Pugh's ratio following the Voigt-Reuss-Hill scheme. As the Al content increases, the mechanical strength increases but the ductility decreases in the Ti-Al compounds. This results from the enhanced covalent bond formed by the continuously enhanced Al-sp hybrid orbitals and Ti-3d orbitals. Nb doping (~5 at.% in this study) keeps the thermodynamical and mechanical stability for the Ti-Al compounds, which exhibit slightly higher bulk modulus and better ductility. This is attributed to the fact that the Nb 4d orbitals locate near the Fermi level and interact with the Ti-3d and Al-3p orbitals, improving the metallic bonds based on the electronic structures.

Theoretical study of physical properties of nanolaminated borides MAlB (M=Cr, Mo, W)

In this study, we have conducted a thorough investigation into the influence of the atomic radius of transition metals on the structural, electronic, and optical properties of nanolaminated borides MAlB ([Formula: see text], Mo, W) using first principles calculation. The validity and dependability of our calculation parameters are confirmed and compared with other available data sets. The calculated elastic constants reveal stronger resistance to deformation along the c direction as compared to the a- and b-directions. The mechanical properties of these borides increased in tandem with the atomic radius of transition metal. The chemical bonding within the borides is a mix of metallic and covalent bonds. Interestingly, there is a decrease in the boride metallicity concurrent with an increase in the atomic radius of the transition metal. Optical property analysis shows promise for these borides as absorbent materials. Furthermore, there is a correlation between the increase in the atomic nucleus of the transition metal and the increase in the maximum absorption coefficient.

Harnessing ZnCr2O4/g-C3N4 nanosheet heterojunction for enhanced photocatalytic degradation of rhodamine B and ciprofloxacin

Utilizing semiconductors for photocatalytic processes in water bodies as an approach to environmental remediation has gained considerable attention. Theoretical band position calculations revealed a type-II step-scheme charge flow mechanism for ZnCr2O4/g-C3N4 (ZCr/gCN), emphasizing effective heterojunction formation due to synergies between the materials. A composite of agglomerated nanoparticle ZnCr2O4 (Zinc chromium oxide - ZCr)/g-C3N4 (graphitic carbon nitride - gCN) nanosheets was synthesized using the ultrasonication and leveraging the heterojunction to enhance degradation efficiency and active sites participation. The synthesized sample was characterized by XRD, XPS, FTIR, BET, HRSEM, EDX, HRTEM, EIS PL, and UV–visible spectroscopy. XRD analysis confirmed the successful formation of pure ZnCr2O4, g-C3N4 (gCN), and their composite without any secondary phases. Optical investigations demonstrated a red shift (444–470 nm) in UV–visible spectra as ZnCr2O4 content increased. Morphological assessment via HRSEM unveiled agglomerated nanoparticle and nanosheet structures. FTIR analysis indicated the presence of gCN with the tri-s-triazine breathing mode at 807 cm−1, and the identification of octahedral Zn–O (598.11 cm−1) and tetrahedral Cr–O (447.01 cm−1) metal bonds within the spinel structure of ZnCr2O4. A Surface area of 134.162 m2/g was noticed with a microporous structure of pore radius 1.484 nm. Notably, the 15% ZCr/gCN composite achieved a remarkable 93.94 % (Rhodamine B–RhB) and 74.36 % (Ciprofloxacin - CIP) within 100 and 120 min, surpassing the performance of pure gCN. Improved degradation was attributed to higher charge separation (photo-excited electrons and holes), reducing charge recombination, as supported by photoluminescence and photoelectrochemical analyses. The presence of active species like superoxide during degradation was confirmed through a scavenger test. The stability analysis confirms the sample's stable nature (without secondary phase formation) after degradation. This work underscores the potential of ZnCr2O4 based metal-free compounds intended for effective environmental remediation.

Automated prediction of ground state spin for transition metal complexes.

Exploiting crystallographic data repositories for large-scale quantum chemical computations requires the rapid and accurate extraction of the molecular structure, charge and spin from the crystallographic information file. Here, we develop a general approach to assign the ground state spin of transition metal complexes, in complement to our previous efforts on determining metal oxidation states and bond order within the cell2mol software. Starting from a database of 31k transition metal complexes extracted from the Cambridge Structural Database with cell2mol, we construct the TM-GSspin dataset, which contains 2063 mononuclear first row transition metal complexes and their computed ground state spins. TM-GSspin is highly diverse in terms of metals, metal oxidation states, coordination geometries, and coordination sphere compositions. Based on TM-GSspin, we identify correlations between structural and electronic features of the complexes and their ground state spins to develop a rule-based spin state assignment model. Leveraging this knowledge, we construct interpretable descriptors and build a statistical model achieving 98% cross-validated accuracy in predicting the ground state spin across the board. Our approach provides a practical way to determine the ground state spin of transition metal complexes directly from crystal structures without additional computations, thus enabling the automated use of crystallographic data for large-scale computations involving transition metal complexes.

Синтез комплексов хрома с углеводородными и гетероциклическими лигандами и применение их в процессах полимеризации и газофазного получения хромкарбидных пленок в работах

In the works of Professor A.N. Artemov, the synthesis of chromium-containing isoxazolines by the reaction of 1,3-lipolar cycloaddition was studied and an increase in cis/trans selectivity was demonstrated when introducing a tricarbonylchromium group into molecules of dipoles and dipolarophiles. Arentricarbonylchromium derivatives of six–membered heterocycles with N–C–O bonds, like their five-membered analogues, can be obtained by reaction between heterocycles free of the tricarbonylchromium group, as well as a result of condensation of chromium-containing amino alcohols with carbonyl compounds. The synthesis of bi- and polymetallic compounds in the reactions of organometallic halides with various non-transition metals has been studied. Such reactions make it possible in a one-step process to obtain compounds containing covalent bonds of metals of 12–15 groups (Mg, Zn, Cd, In, Tl, Sn, Pb, Bi) with non-transitive elements (Fe, Mo, W). Styrene chromium tricarbonyl, para-methylstyrene chromium tricarbonyl, α-methylstyrene chromium tricarbonyl, stilbene chromium tricarbonyl, allylbenzene chromium tricarbonyl, and diphenylbutadiene chromium tricarbonyl were studied as polymerization regulators by the mechanism of reversible inhibition for vinyl monomers. α-methylstyrene chromium tricarbonyl, diphenylbutadiene chromium tricarbonyl, allylbenzene chromium tricarbonyl. When they are introduced into the polymerizing mass of methyl methacrylate, butyl acrylate, styrene in quantities commensurate with the concentration of the initiator, they control the termination of the polymer chain at temperatures not exceeding 100 °C. At the same time, the process proceeds at a sufficiently high rate, and the control of chain growth follows the mechanism of reversible inhibition. The gas-phase decomposition of bis-ethylbenzenechromium can proceed with the formation of hard and wear-resistant chromium carbide coatings, as well as with the production of chromium films characterized by a low temperature resistance coefficient.

Fabrication and Formation Principle of Porous Cu-Sn Bumps for Metal Bonding in Chiplet Integration

Fabrication and Formation Principle of Porous Cu-Sn Bumps for Metal Bonding in Chiplet Integration

First-principles study of stability and electronic structural properties of Ag/Au/M (Cu, Ni) interface

This study investigated the interface energy, work of adhesion, and electronic structural properties at the Ag/Au/M(Cu,Ni) interface, employing the first-principles method based on density functional theory. First, the structures of various binary and ternary interfaces were optimized. Subsequently, the total density of states (TDOS), partial density of states (PDOS), charge distribution, and bonding characteristics of these interfaces were investigated. Additionally, the interface energy and work of adhesion of these interfaces were calculated. The results indicated that the Ag/Au/Ni interface exhibited higher stability and bonding strength compared to the Ag/Au/Cu interface. The contribution of the PDOS of atoms at the Ag/Au/M(Cu,Ni) interface to the TDOS can be primarily attributed to d-orbital electrons, while s- and p-orbit electrons had minimal influence on PDOS.Notably, d-d orbital hybridization emerged between the d-orbit electrons in Cu and Ni atoms and those in Ag and Au atoms, enhancing structural stability. Two distinct peaks in the TDOS of Ag/Ni, Au/Ni, and Ag/Au/Ni interfaces appeared near the Fermi level, corresponding to d-d orbital hybridization involving Ni, Ag, and Au atoms. At the Ag/Au/Cu and Ag/Au/Ni interfaces, resonance peaks corresponding to the s and p orbits of Ag and the s and p orbits of Au, as well as the d orbits of Ag and Au, indicated the presence of a relatively strong metallic bond between Ag and Au atoms. Furthermore, the Ag/Ni and Au/Ni systems exhibited greater average electron transfer compared to the Ag/Cu and Au/Cu systems. Moreover, atomic bond lengths at the Ag/Au/Ni interface were significantly less than those at the Ag/Au/Cu interface, indicating higher stability of the Ag/Au/Ni interface compared to the Ag/Au/Cu interface.

Intercluster charge ordering in monoclinic and triclinic Ba–Mo-based hollandite phases

Reproducible synthesis of the three distinct crystal types of Mo-based hollandites. Metal–metal bond orders correlate to electron count per metal.

Effects of metal–metal bonding in photosensitizers: red-shifted absorption and oscillator strength enhancement

Metal–metal bonds facilitate a red-shift in the maximum absorption wavelength and an enhancement of the oscillator strength in photosensitizers.

Largely enhanced compressive strength and plastic deformation of Fe-doped all-d-metal heusler alloy Cr2CoV

The structure dynamic stability, magnetic property, strength, and plastic deformation of all-d-metal Heusler alloys Cr2Co1-xFexV (x = 0, 0.2, 0.4, 0.6, 0.8, and 1) have been investigated in this study. It is found that Cr2Co1-xFexV alloys tend to crystalize in the XA-type Heusler phase. The atomic radius becomes the decisive factor in determining the lattice size. With the increase of Fe concentration, the interaction between Cr(B)-Fe atoms increases, resulting in the increase of Curie temperature. The magnetic moments of the Cr2CoV and Cr2FeV are analyzed in conjunction with the theoretical calculations. The ductility and compressive strength of the materials gradually increase with the increase of Fe content. Especially in Cr2FeV alloy, a high compressive strength of up to 3050 MPa and a large ductility of up to 61% are achieved, and no fracture occurs, showing excellent mechanical properties. The electron localization function diagram shows that d-d orbital hybridization is formed and weak in Cr2CoV and Cr2FeV alloys, which helps to form metal bonds. Consequently, the ductility of the all-d-metal Heusler alloys was improved, which increased the fatigue life in practical application.

4,4-Bis(isopropylthio)-1,1-diphenyl-2-azabuta-1,3-diene Adducts with Cadmium(II), Mercury(II) and Copper(I) Iodides: Crystal, Molecular and Electronic Structures of d10 Transition Metal Chelate Complexes

The thioether-functionalized 2-azabutadiene (iPrS)2C=C(H)-N=CPh2 L ligates to CdI2 and HgI2 to form the chelate compounds [CdI2{(iPrS)2C=C(H)-N=CPh2] (1) and [HgI2(iPrS)2C=C(H)-N=CPh2] (2). Their crystal structures were solved via X-ray diffraction. Both crystallize in the non-centrosymmetric space groups: monoclinic P21 (1) and orthorhombic P212121 (2), respectively. The closed-shell d10 metal centers are four-coordinated (two iodides and S and N coordinating atoms from the ligand L) in both complexes. The geometrical indexes τ indicate that a highly distorted trigonal pyramidal is adopted for 1 and a seesaw geometry for 2. The comparative nature of metal–ligand bonds is discussed on the basis of metric parameters and of QT-AIM (quantum theory of atoms in molecules) calculations. L was also treated with CuI to obtain the dinuclear species [LCu(μ2-I2)CuL] (3), in which the two Cu(I) centers are linked by a short metal–metal bond. The geometric and electronic properties of 3 are compared with those of 1 and 2.

SAB-Enabled Room Temperature Hybrid Bonding

3D integration is gaining more and more interest for a large panel of applications including CMOS Image Sensor, High Performance Computing, DRAM including HBM stacks and display. Image sensors based on hybrid bonding 3D stacking are the state-of-the-art in imaging applications[1]. Highest integration densities with micron-size pixels are achieved using copper-oxide hybrid bonding in advanced CMOS Image Sensor (CIS) processes. Recently, functional imagers with sub 1 µm pitch of hybrid bonding interconnection have shown great performances in term of reliability [2]. Hybrid bonding low temperature (< 300°C) is increasingly requested by the industry to reduce thermal budget of sensible chips integration such as Image sensors, displays, or memory. Surface Activated Bonding (SAB) is one of the most promising method to enable very low temperature hybrid bonding as very early proposed by Suga et al [3]. Up to know, they have been mainly performed using modified SAB technology [4] or with Oxide recess [5].In this study, 200 mm wafers with 2.5 µm copper pads spaced 2.5 µm apart (5 µm pitch) in a silicon oxide matrix are used. SAB uses argon atom bombardment as surface activation. This bombardment is performed in UHV (ultra- high vacuum) at room temperature during several tens of seconds. Surface copper oxide is removed during the activation, leaving dangling metallic bonds on copper pads surface. Under UHV, two identical wafers are then immediately bonded at RT under a low pressure of 0.3 MPa. Noteworthy, no precise alignment is performed for this hybrid bonding. In order to better understand bonding behavior, a first part of the study focuses on the etching effect due to argon bombardment. AFM (Atomic force microscope) inspections are performed on such activated hybrid surfaces. Then the SAB bondings are characterized by SAM (Scanning Acoustic Microscopy) with or without annealing at 150°C and 200°C during 2 hours. Once the top silicon is removed by grinding, further characterizations such as TEM (Transmission Electron Microscopy) and ACOM (Automated Crystal Orientation Mapping) are carried out. For comparison purposes, standard atmospheric hybrid bonding samples are also fabricated at an annealing temperature between 200°C and 300°C. They are characterized in the same way.SAB for hybrid bonding proves its relevance in this study. Indeed, all bonded samples are successfully grinded and thinned out leaving only the damascene structure (which thickness is around 1 µm) above the bonding interface. Despite oxide/oxide and copper/oxide weak SAB interface, the thinning success for the non-annealed sample demonstrates that enough copper/copper interfaces are successfully obtained. As first suggested by AFM scans after surface activation (Figure 1) and subsequently confirmed by SAM, optimized CMP dishing and etching generated during the SAB activation step allow contacting the copper pads at room temperature. However, improved bonding closure is shown by SAM on the annealed samples. Besides, TEM sections show an excellent copper bonding interface on every SAB samples, even those without annealing. These characterizations have been performed on both SAB hybrid bonding samples and atmospheric ones, allowing comparing both processes and a better understanding of hybrid SAB ones. As could be seen on figure 2, the great copper bonding quality could be summarized by a rebuilt of the copper grains (triple grain boundaries at the interface) and the presence of few defects in the bonding pads. In addition, ACOM provides information about the crystallography of the copper pads all over a section in the bonding. SAB seems to have an effect on the pad crystallography. This will be discuss regarding the process differences.To sum up, bonding of hybrid surfaces at room temperature is successfully realized thanks to SAB. SAM characterizations after bonding, mechanical strength in grinding and TEM images confirm that this process is more than promising in the field of low temperature hybrid bonding. In the wake of these encouraging results, new vehicles including electric test structures are to be bonded with alignment in a SAB system. This new study will allow not only to validate the process on aligned bonded structures but also to qualify the electrical performances of hybrid SAB. Figure 1

Theoretical study on the structural, electronic, mechanical, vibrational, thermodynamical, and optical properties of the two-dimensional PbC nanomaterials

Two-dimensional structures have attracted attention for application in nanoelectronics and optical devices; then, in this work, we are reporting the predicted physical properties (from first-principles calculations) for the two-dimensional PbC systems. Those physical properties reveal that the PbC monolayers (M-PbCs) in crystallographic planes (111) and (100); moreover, the PbC2 structures (paramagnetic and anisotropic compounds) are thermodynamical, structural, and mechanically stable but energetically and dynamically unstable at T = 0 K. However, the PbC2 non-magnetic (NM) is the most stable system at high temperatures. The M-PbCs exhibit sp 2 hybridization while the PbC2 NM shows sp 3 d 2 hybridization, forming a hexagonal lattice; meanwhile, the strong interaction at the C’s double bond in the PbC2 ferro and antiferromagnetic configurations (MAG) generates a rectangular lattice. These systems are ductile materials; however, the PbC2 (with metallic bonds) is more ductile than the M-PbCs due to the pronounced participation of the Pb 6p-orbitals. The M-PbCs have associated greater values for the hardness (than those for the PbC2 systems), but at high temperatures, the PbC2 MAG exhibits the highest mechanical resistance. The calculated optical data show that the M-PbCs and the PbC2 NM are promising as refractory materials. At the same time, the PbC2 MAG could be helpful in optical and optoelectronic devices capable of operating in the low frequencies of the UV region and in the infrared and visible regions.