- 标题
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- 实验方案
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Assessment of the Microstructure and Mechanical Properties of a Laser-Joined Carbon Fiber-Reinforced Thermosetting Plastic and Stainless Steel
摘要： The thermosetting plastic and stainless steel were joined with a fiber laser. The influence of processing parameters on the joint was studied. The laser scanning on stainless steel is shown to result lathy ferrite precipitates along the boundary, which modifies austenite, while in the second zone, ferrite forms the skeleton structure and separates austenite into a small cellular structure. The laser joining improves the microstructure of both zones. With an increase in the laser scanning speed and power, the shear strength of the stainless steel/plastic joint first increases and then decreases. A low laser scanning speed or high laser power would overheat polyphenylene sulphide and lead to its decomposition. Those factors would also reduce heat transfer and lead to its insufficient melting. The stainless steel/plastic joint acquires a maximum shear strength at a laser scanning speed of 4–5 mm/s and laser power of 320-350 W.
关键词： bonding interface,laser joining,microstructure,carbon fiber-reinforced thermoplastic,stainless steel,shear strength
更新于2025-09-10 09:29:36
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Solvothermal syntheses, structures and fluorescent properties of six ZnII/CdII coordination polymers constructed from N-donor ligands and multidentate organic acid
摘要： Six new coordination polymers(CPs) {[Cd(L1)(CHDA)]·H2O}n (1), [Zn3(L1)2(1,2,4-BTC)2(H2O)4]n (2), [Zn(L2)(D-CAM)(H2O)]n (3), [Zn3(L2)(1,2,4-BTC)2(H2O)4]n (4), [Cd(L2)(1,3,5-HBTC)]n (5) and {[Zn(L2)(4,4′-BOA)]·H2O}n (6) (L1 = 3,6-bis(imidazol-1-yl)pyridazine, L2 = 3,6-bis(benzimidazol-1-yl)pyridazine, 1,4-H2CHDA = (1 S,4 S)-cyclohexane-1,4-dicarboxylic acid, D-CAM = (1 R,3 S)-1,2,2-trimethylcyclopentane-1,3-dicarboxylic acid, 1,3,5-H3BTC = benzene-1,3,5-tricarboxylic acid, 4,4′-H2OBA = 4,4′-oxydibenzoic acid) were achieved by reactions of the corresponding metal salt with mixed organic ligands. Their structures were determined by single-crystal X-ray diffraction, IR spectra, elemental analysis, powder X-ray diffraction and thermogravimetric analysis. They exhibit varied structures, complexes 4 and 5 are porous three-dimensional (3D) frameworks, while 2 and 3 are 3D supermolecule structure formed by hydrogen-bonding interactions, and 1 is a two-dimensional (2D) network and 6 is an infinite one-dimensional (1D) chain. In addition, the fluorescent emission, fluorescence lifetimes of L1, L2 and 1–6 have been investigated and discussed.
关键词： Fluorescence lifetimes,Hydrogen-bonding interactions,Coordination polymers (CPs),Polycarboxylate ligands
更新于2025-09-10 09:29:36
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<i>(Invited)</i> Monolithic Integration of Si-CMOS and III-V-on-Si through Direct Wafer Bonding Process
摘要： Integration of Si-CMOS and III-V compound semiconductors (with device structures of either InGaAs HEMT, InGaP LED, GaAs HBT, GaN HEMT or InGaN LED) on a common Si substrate is demonstrated. The Si-CMOS layer is temporarily bonded on a Si handle wafer. Another III-V/Si substrate is then bonded to the Si-CMOS containing handle wafer. Finally, the handle wafer is released to realize the Si-CMOS on III-V/Si substrate. For GaN LED or HEMT on Si substrate, additional wafer bonding step is required to replace the fragile Si (111) substrate after high temperature GaN growth with a new Si (001) wafer to improve the robustness of the GaN/Si wafers. Through this substrate replacement step, the bonded wafer pair can survive the subsequent processing steps. The monolithic integration of Si-CMOS + III-V devices on a common Si platform enables new generation of systems with more functionality, better energy efficiency, and smaller form factor.
关键词： III-V compound semiconductors,Si-CMOS,wafer bonding,HEMT,GaN LED,monolithic integration
更新于2025-09-10 09:29:36
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High-Pressure Synthesis, Crystal Structure, Chemical Bonding, and Ferroelectricity of LiNbO <sub/>3</sub> -Type LiSbO <sub/>3</sub>
摘要： A polar LiNbO3 (LN)-type oxide LiSbO3 was synthesized by a high-temperature heat treatment under a pressure of 7.7 GPa and found to exhibit ferroelectricity. The crystal structural re?nement using the data of synchrotron powder X-ray di?raction and neutron di?raction and the electronic structure calculation of LN-type LiSbO3 suggest a covalent-bonding character between Sb and O. When comparing the distortion of BO6 in LN-type ABO3, the distortions of SbO6 in LiSbO3 and SnO6 in ZnSnO3, which included a B cation with a d10 electronic con?guration, were smaller than those of BO6 in LN-type oxides having the second-order Jahn?Teller active B cation, e.g., LiNbO3 and ZnTiO3. The temperature dependence of the lattice parameters, second harmonic generation, dielectric permittivity, and di?erential scanning calorimetry made it clear that a second-order ferroelectric?paraelectric phase transition occurs at a Curie temperature of Tc = 605 ± 10 K in LN-type LiSbO3. Further, ?rst-principles density functional theory calculation suggested that perovskite-type LiSbO3 is less stable than LN-type LiSbO3 under even high pressure, and the ambient phase of LiSbO3 directly transforms to LN-type LiSbO3 under high pressure. The phase stability of LN-type LiSbO3 and the polar and ferroelectric properties are rationalized by the covalent bonding of Sb?O and the relatively weak Coulomb repulsion between Li+ and Sb5+.
关键词： high-pressure synthesis,LiNbO3-type oxide,covalent bonding,ferroelectricity,second-order Jahn?Teller effect,LiSbO3
更新于2025-09-10 09:29:36
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[IEEE 2018 7th Electronic System-Integration Technology Conference (ESTC) - Dresden, Germany (2018.9.18-2018.9.21)] 2018 7th Electronic System-Integration Technology Conference (ESTC) - Multi dies simultaneous bonding for power device with the newly developed pressure leveling film
摘要： The performance of the newly developed film to level the applied pressure among dies in the process of multi dies simultaneous bonding was evaluated. Sintering Ag paste was used as pre-applied connection material. The leveling performance was evaluated by nine dies simultaneous bonding. The height of the dies was intentionally differed one another, which was controlled by a SUS tape insertion between the bonding tool and the dies. The film compensated the height difference of up to 50 μm in the bonding process. The results of the cross sectional observation after the bonding showed that the dense sintered Ag layer was formed uniformly in all dies in spite of with and without the SUS tape insertion on the backsides of the dies.
关键词： bonding,force leveling film (BFL),sintering Ag paste,high productivity,simultaneous bonding,thermal compression bonding (TCB)
更新于2025-09-09 09:28:46
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[IEEE 2018 19th International Conference on Electronic Packaging Technology (ICEPT) - Shanghai (2018.8.8-2018.8.11)] 2018 19th International Conference on Electronic Packaging Technology (ICEPT) - Optimization of Gold Wire Bonding Process for Microwave Components by DOE Method
摘要： In this paper, the gold wire bonding process of microwave components was studied by design of experimental (DOE) method, and the multiple linear regression equation of the pulling force corresponding with bonding parameters was obtained through the analysis of variance (ANOVA). Results showed that the degree of experimental factors influence on the pulling force was as follows: bonding power>bonding temperature>bonding pressure>ultrasonic time>deformation. Additionally, the initial optimized parameter combination was got: the bonding temperature was 130 °C, the bonding pressure was 25 cN, the bonding power was 0.50 W, the ultrasonic time is 60 ms, and the deformation was 60%. The pulling force of wire bonding can be controlled in the range of 10.0 to 10.5 gf by the optimized combination of bonding parameters.
关键词： bonding power,pulling force,gold wire bonding,Microwave components,DOE,Regression fitting
更新于2025-09-09 09:28:46
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Room Temperature Bonding of Wafers Using Si and Ge Films with Extremely Low Electrical Conductivity
摘要： The technical potential of room temperature bonding of wafers in vacuum using amorphous Si (a-Si) and Ge (a-Ge) films was studied. Transmission electron microscopy images revealed no interface corresponding to the original films surfaces for bonded a–Ge–a–Ge films. Analyses of film structure and the surface free energy at the bonded interface revealed higher bonding potential at the connected a–Ge–a–Ge interface than that of a–Si films. The electrical resistivity of a-Ge films is 0.62 ?m, which is lower than that of a-Si film (4.7 ?m), but 7–8 order higher than that of representative material films used for bonding in vacuum. Our results indicate that room temperature bonding using a–Ge films is useful to bond wafers without any marked influence on the electrical properties of devices on wafer surfaces caused by the electrical conductivity of films used for bonding.
关键词： room temperature bonding,electrical conductivity,amorphous Ge,wafer bonding,amorphous Si
更新于2025-09-09 09:28:46
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Epitaxial Bonding and Transfer Processes for Large-Scale Heterogeneously Integrated Electronic-Photonic Circuitry
摘要： A process ?ow for the heterogeneous integration of III-V epitaxial material onto a silicon host wafer using CMOS-compatible materials and methods toward the goal of forming electronic-photonic circuitry is presented. Epitaxial structures for compound-semiconductor-based transistors are assembled on a silicon carrier wafer using a commercially-available polymer and then formed into distinct patterns for scalable processing. A CMOS-compatible metallization process is performed on the back side collector terminal of the aligned epitaxial structures, followed by a metal-eutectic bonding process that transfers the wafer-scale array of III-V material onto a separate silicon host wafer allowing the fabrication of both electronic and photonic devices on a single wafer. Characterization of the epitaxial bonding and transfer is performed to ensure material alignment is maintained without additional tooling and that the interconnect layer established between III-V collector and silicon host wafer performs as an ohmic contact, thermal path, and mechanical bond compatible with back-end-of-line (BEOL) integrated circuit processing. These processes are shown for GaAs-based light-emitting transistor (LET) epitaxial material to demonstrate that subsequent photonic devices and systems may be patterned into the integrated material allowing a direct electrical interconnect to embedded CMOS-based electronic systems for new functionalities as electronic-photonic integrated circuitry.
关键词： epitaxial bonding,silicon host wafer,metal-eutectic bonding,III-V epitaxial material,electronic-photonic circuitry,heterogeneous integration,CMOS-compatible
更新于2025-09-09 09:28:46
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Preface: Two dimensional (2D) hybrid organic-inorganic perovskites
摘要： 2D hybrid organic-inorganic perovskites (HOIPs) have been intensively investigated over the past 30 years before the rise of photovoltaic 3D hybrid perovskites. Along with the increasing research interest on 2D materials, they have attracted much attention. On the one hand, 2D hybrid perovskites possess much improved photo- and chemical stability over their 3D counterparts. On the other hand, the delicate interplay of multiple atomic bonding forces in the crystal lattice enables them to exhibit extraordinary properties that traditional inorganic 2D materials are unable to show. More importantly, the chemical and structural diversity of 2D HOIPs offers greater opportunities to fine-tune and engineer properties and functionalities compared with their 3D counterparts.
关键词： chemical and structural diversity,atomic bonding forces,photo- and chemical stability,2D hybrid organic-inorganic perovskites,photovoltaic
更新于2025-09-09 09:28:46
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H-bonding Effect of Oxyanions Enhanced Photocatalytic Degradation of Sulfonamides by g-C3N4 in Aqueous Solution
摘要： In this study, the effect of oxyanions on the photodegradation of sulfonamides by graphitic carbon nitride (g-C3N4) was investigated. The results showed that the presence of disilicate (DS) could substantially improve the photodegradation of sulfamethazine (SMZ) in g-C3N4 aqueous suspension. The primary mechanism for the enhancing effect of DS was hydrogen bonding (H-bonding) interaction. The hydroxyl groups (-OH) and bridging oxygen (Si-O-Si) of DS can form H-bonds with the amine groups of g-C3N4 particles and sulfonamides, therefore soluble DS can act as a bridge to enhance the transfer and adsorption of SMZ onto the surface of g-C3N4 particles. The presence of DS did not change the mechanism of photodegradation, but there was an optimal concentration for DS to achieve the strongest enhancing effect. H-bonding effect was also found for other oxyanions derived from weak acids, such as silicate, dihydrogen phosphate and borate ions, because the partial ionization of these oxyanions allowed the existence of hydroxyl groups to form H-bonds. The present study not only deepens our understanding of the interface process of the photodegradation of sulfonamides in g-C3N4 aqueous suspension, but also provides a potential method to enhance the photocatalytic degradation of antibiotics in wastewater streams.
关键词： Carbon nitride,Oxyanions,Photocatalysis,Hydrogen bonding,Sulfonamides
更新于2025-09-09 09:28:46