High Packing Density Research Articles

Natural bio-waste-derived 3D N/O self-doped heteroatom honeycomb-like porous carbon with tuned huge surface area for high-performance supercapacitor

Supercapacitor electrodes (SCs) of carbon-based materials with flexible structures and morphologies have demonstrated excellent electrical conductivity and chemical stability. Herein, a clean and cost-effective method for producing a 3D self-doped honeycomb-like carbonaceous material with KOH activation from bio-waste oyster shells (BWOSs) is described. A remarkable performance was achieved by the excellent hierarchical structured carbon (HSC-750), which has a large surface area and a reasonably high packing density. The enhanced BWOSs-derived HSC-750 shows an ultrahigh specific capacitance of 525 F/g at 0.5 A g−1 in 3 M KOH electrolyte, as well as high specific surface area (2377 m2 g−1), pore volume (1.35 cm3 g−1), nitrogen (4.70%), and oxygen (10.58%) doping contents. The SCs also exhibit exceptional cyclic stability, maintaining 98.5% of their capacitance after 10,000 charge/discharge cycles. The two-electrode approach provides a super high energy density of 28 Wh kg−1 at a power density of 250 W kg−1 in an alkaline solution, with remarkable cyclability after 10,000 cycles. The study demonstrates the innovative HSC synthesis from BWOSs precursor and cost-effective fabrication of 3D N/O self-doped heteroatom HSC for flexible energy storage.

Direct Observation of Enhanced Iodine Binding within a Series of Functionalized Metal-Organic Frameworks with Exceptional Irradiation Stability.

Optimization of active sites and stability under irradiation are important targets for sorbent materials that might be used for iodine (I2) storage. Herein, we report the direct observation of I2 binding in a series of Cu(II)-based isostructural metal-organic frameworks, MFM-170, MFM-172, MFM-174, NJU-Bai20, and NJU-Bai21, incorporating various functional groups (-H, -CH3, - NH2, -C≡C-, and -CONH-, respectively). MFM-170 shows a reversible uptake of 3.37 g g-1 and a high packing density of 4.41 g cm-3 for physiosorbed I2. The incorporation of -NH2 and -C≡C- moieties in MFM-174 and NJU-Bai20, respectively, enhances the binding of I2, affording uptakes of up to 3.91 g g-1. In addition, an exceptional I2 packing density of 4.83 g cm-3 is achieved in MFM-174, comparable to that of solid iodine (4.93 g cm-3). In situ crystallographic studies show the formation of a range of supramolecular and chemical interactions [I···N, I···H2N] and [I···C≡C, I-C═C-I] between -NH2, -C≡C- sites, respectively, and adsorbed I2 molecules. These observations have been confirmed via a combination of solid-state nuclear magnetic resonance, X-ray photoelectron, and Raman spectroscopies. Importantly, γ-irradiation confirmed the ultraresistance of MFM-170, MFM-174, and NJU-Bai20 suggesting their potential as efficient sorbents for cleanup of radioactive waste.

Effect of High-Density Packing Recycled Aggregate on Concrete Strength Properties

As many residential homes and structures were destroyed or badly damaged because of the military battle in Iraq, it is critical to recycle construction debris widely in the rebuilding and decoration of buildings and infrastructure. This battle resulted in the buildup of massive construction debris, and recycling this waste allows for a cleaner environment. Recycling the construction waste of various installations is an urgent need to decrease the consumption of natural materials and landfills of construction waste, and as a result reduce the environmental pollution. Therefore, this study is a local focus on using concrete debris to obtain high packing density recycled coarse and fine aggregates in various fractions of (0.16 mm - 10 mm) by selecting high-density packing materials that was developed by Kharkhadin A.N in laboratories of Belgorod State Technical University in Russia to preparing of reference mix from ordinary density recycled aggregate. The new concrete samples for two concrete mixtures were prepared, to identify and study the important specifications. Models of cubes and standard prisms were prepared to evaluate the compressive strength and the splitting tensile strength. Also, the modulus of rupture and the unit weight were conducted. The results indicated an increase in the concrete’s mechanical properties using the high-packing density recycled aggregate. The obtained compressive strength, splitting tensile strength and modulus of rupture were (49) MPa, (3.6) MPa, and (7.1) MPa compared with a reference mix (39) MPa, (3.3) MPa and (6.3) MPa, respectively. The reference mix corresponding properties were (39) MPa, (3.3) MPa, and (6.3) MPa, respectively. Also the values of an oven-dry density were (2340) kg/m3 compared with the reference mix (2260kg/m³). These results proved that increasing the packing density of recycled aggregate enhanced the concrete’s strength properties.

Enhancing Lifetime and Performance of MLC NVM Caches Using Embedded Trace Buffers

Large volumes of on-chip and off-chip memory are required by contemporary applications. Emerging non-volatile memory technologies including STT-RAM, PCM, and ReRAM are becoming popular for on-chip and off-chip memories as a result of their desirable properties. Compared to traditional memory technologies such as SRAM and DRAM, they have minimal leakage current and high packing density. Non Volatile Memories (NVM), however, have a low write endurance, a high write latency, and high write energy. Non-volatile Single Level Cell (SLC) memories can store a single bit of data in each memory cell, whereas Multi Level Cells (MLC) can store two or more bits in each memory cell. Although MLC NVMs have substantially higher packing density than SLCs, their lifetime and access speed are key concerns. For a given cache size, MLC caches consume 1.84× less space and 2.62× less leakage power than SLC caches. We propose Trace buffer Assisted Non-volatile Memory Cache (TANC), an approach that increases the lifespan and performance of MLC-based last-level caches using the underutilized Embedded Trace Buffers (ETB). TANC improves the lifetime of MLC LLCs up to 4.36× and decreases average memory access time by 4% compared to SLC NVM LLCs and by 6.41× and 11%, respectively, compared to baseline MLC LLCs.

Construction of micro-tubular proton-conducting ceramic electrochemical reactor (MT-PCER) for ammonia production at atmospheric pressure

Micro-tubular ceramic electrochemical reactors have attracted significant interest due to their high packing density, large electrode specific surface area, and long triple phase boundaries (TPBs). In this work, a micro-tubular proton-conducting ceramic electrochemical reactor (MT-PCER) with a unique microstructure is facilely constructed for ammonia synthesis at atmospheric pressure. BaCe0.7Zr0.1Y0.2O3-δ (BCZY as the electrolyte)/Ni–BaCe0.7Zr0.1Y0.2O3-δ (Ni-BCZY as the catalytic cathode) dual-layer hollow fibers with open finger-like pores on the inner surface are first fabricated using a modified co-spinning/co-sintering process to form a basic MT-PCER. Fe-based catalyst was then coated into these open finger-like pores in Ni-BCZY layer as an additional catalytic cathode of the MT-PCER. The unique open finger-like pores structure of the basic MT-PCER decreases the mass transfer resistance and also provides space for loading additional catalysts, contributing towards the higher catalytic performance of the MT-PCER. However, the Faradaic efficiency for ammonia formation remained low, indicating that the cathode catalyst required further improvement. This fabrication technique provides a flexible method to adjust the cathode catalysts to optimize the catalytic performance of the MT-PCERs.

Electrochemical deposition of Sn-0.7Cu alloy modified with nano-WO3 for high-density mini-LED packaging

Electrochemical deposition of Sn-0.7Cu alloy modified with nano-WO3 for high-density mini-LED packaging

Leveraging tannic acid-ferric iron (TA/Fe3+) complexation in polyamide selective layer for synthesizing robust thin film composite reverse osmosis (TFC-RO) hollow fiber membranes for saline water treatment

The high efficiency and adaptability of reverse osmosis (RO) are two main reasons this separation technology is accepted worldwide, depending on its various uses, such as water purification, desalination, and concentration. The potential of RO can be enhanced by utilizing the hollow fiber (HF) mode, benefiting from higher packing density, ease of cleaning, and cost competitiveness. However, its suitability for RO applications becomes questionable due to its weaker and fragile mechanical resilience. To solve the abovementioned issue and improve the mechanical strength and burst/crush pressure, we propose optimizing the selective layer of the TFC-RO membrane using tannic acid complexation with FeCl3. The polyethersulfone (PES) support layer was initially fabricated to host the polyamide (PA) layer. Subsequently, the introduction of tannic acid-ferric chloride complexation was implemented as a sandwich layer between the aqueous and organic phase reactions to host a coherent and selective PA layer to further enhance its performance by controlling the kinetics of interfacial polymerization (IP). The surface morphology, physicochemical properties, and underlying reactions were analyzed using scanning electron microscopy (SEM), atomic force microscope (AFM), Fourier infrared spectroscopy (FTIR), x-ray photoelectron spectroscopy (XPS), and water contact angle measurements. The TFC-RO membrane M_TA0.2/Fe7.5 (7.5 mM FeCl3 & 0.2 wt% tannic acid) showed significant improvement in pure water permeance and salt rejection along with 7.23 MPa of burst pressure and 68.41 % strain, which proves superior elasticity and mechanical robustness because of PA TA/Fe3+ complexes formed during the IP. Moreover, the proposed facile tannic acid modification is effective and scalable. It significantly improves the mechanical efficacy of the HF TFC-RO membrane, solving a great problem for its commercial adaptability for RO applications and paving the way for smoother industrial translation for direct human factor applications.

Wall-mounted ultrafine hollow fiber membrane module for purification of domestic surface water

The World Health Organization (WHO) estimated that around 844 million people worldwide lack safe drinking water, including 159 million who are dependent only on surface water. Investing in a practical, sustainable, and cost-effective treatment process is indispensable to alleviating the effect of water shortage. Besides water treatment, ultrafiltration (UF) membranes are broadly used in protein fractionation and clarification of fruit juices. The hollow fiber (HF) membrane configuration has a much larger surface area per unit volume, resulting in higher productivity than the flat-sheet membrane. A spinneret was developed with a provision for altering the fiber's inner diameter from 1000 µm to 150 µm and outer dimension from 1500 µm to 350 µm, respectively, using an inbuilt detachable needle arrangement. The ultrathin hollow fiber produced by the indigenously designed spinnerets has a high surface area and packing density, which makes it useful for surface water treatment. A wall-mounted module was designed for direct connection to the tap to obtain a purified water flow of 30–40 liter per hour (LPH) for domestic use, operated with or without electricity. The fabricated ultrafine HF module (ID: 150–200 µm; OD: 350–450 µm) removes complete bacterial contamination and turbidity up to 95–100 %, making the quality of processed water potable. The developed membrane module is durable due to its large membrane area per unit volume, enhancing productivity, high packing density, good fouling resistance, easy handling, and self-supporting structure for backwashing. The present research article paves the way forward to investing in a practical, sustainable, and economical treatment process that is indispensable to alleviating the effect of water shortage.

Investigating and characterizing electrical properties of polypyrrole/SiO2/FePS3 nanocomposite

AbstractNovel nanocomposites of polypyrrole (PPy) embedded in silica (SiO2) and iron phosphorus trisulphide (FePS3) nanoparticles have been fabricated. The nanocomposite's dielectric characteristics have been examined in relation to temperature ranges of 25–200°C and frequency ranges of 0.1–7 MHz. Fourier‐transform infrared spectroscopy (FTIR), x‐ray diffraction (XRD), scanning electron microscopy (SEM–EDX), transmission electron microscope (TEM), and dielectric measurements have all been used to evaluate the prepared nanocomposite. The monoclinic crystal structure of the prepared FePS3 and PPy/SiO2/FePS3 nanocomposite is confirmed by XRD, EDX, and TEM studies. The FePS3 is perfectly layered structure in the SEM image, and FePS3 and SiO2 particles are well intercalated, creating novel nanocomposites of two nanoparticle phases that served as a union network during the polymerization process. The IR spectrum shows that PPy is a dopant in the interlayer area of FePS3. The splitting major peak (570 cm−1) of FePS3 is visible at around 640 and 560 cm−1. The high AC conductivity values indicated that the combination of FePS3/SiO2 nano‐matrix contains PPy at high packing densities and confirming the semiconducting properties of the nanocomposite to be used in several electronic applications.

Efficient C2H2/CO2 separation in two 2-fold interpenetrating metal-organic frameworks with ultrahigh C2H2 packing density

Adsorptive separation of C2H2/CO2 is industrially important and feasible but the design of highly efficient adsorbents remains very challenging owing to the almost identical physicochemical properties of the two gases. Herein, we constructed two new microporous metal–organic frameworks (MOFs), termed CTGU-39/40 (CTGU = China Three Gorges University), with 2-fold interpenetrating frameworks and unique pore geometry/chemistry for C2H2/CO2 separation. Both the activated MOFs (CTGU-39/40-a) can preferentially adsorb C2H2 over CO2 with excellent selectivity of 8.4 and 3.3 at 298 K and 100 kPa, respectively, as verified by static adsorption measurements. More importantly, attributed to the suitable pore aperture size (∼5 Å) and abundant adsorption sites, CTGU-39-a combines exceptionally high packing density of C2H2 (0.41 g mL−1) and moderate isosteric heat of adsorption (Qst) for C2H2 (26.8 kJ mol−1), outperforming most previously reported adsorbents. Theoretical calculations reveal that the preferential adsorption of C2H2 within two MOFs is driven by cooperative adsorption behavior through multiple H-bonding and Coulomb interactions. Experimental breakthrough results further confirmed their practical separation ability and recyclability toward an equimolar C2H2/CO2 mixture at different feeding rates. This work may offer new insights into the design of advanced porous materials for C2H2 purification and potentially other gas separations.

Efficient and economic water and heat recovery from flue gas by novel hydrophilic polymeric membrane condenser

The membrane technology for water and heat recovery from flue gas possesses the advantages of a simple structure and high water quality. In this study, we propose a novel hydrophilic polymeric membrane condenser (HPMC) to efficiently recover water and heat from flue gas. Compared to current hydrophilic ceramic membrane condenser (HCMC), HPMC offers the benefits of cost-effectiveness and high packing density. An experimental investigation is conducted to explore the fluid flow characteristics as well as the water and heat recovery performance of HPMC. The maximum recovered water flux reaches 6.7 kg/(m2·h), while the maximum recovered heat flux amounts to 18.6 MJ/(m2·h). Enhancing gas/water flow rates or increasing heat transfer temperature difference can significantly improve both recovered water and heat fluxes. Notably, it is found that thermal resistance primarily stems from the polymeric membrane, emphasizing the importance of enhancing the membrane's thermal conductivity to improve HPMC performance. The overall heat transfer coefficient can be enhanced by increasing the gas/water flow rate, while the influence of gas/water temperature on the overall heat transfer coefficient is relatively insignificant. Furthermore, by fitting experimental data, a correlation formula for friction factor is obtained, which greatly enhances accuracy in pressure drop calculations under practical operating conditions. Based on the technical and economic analysis, the payback period for HPMC is merely 0.3 years, significantly shorter than that for HCMC, thereby indicating a substantial potential for commercial application of HPMC. This study demonstrates that the HPMC is an excellent candidate for recovering water and heat from flue gas, and the fundamental data provides valuable foundational insights for future enhancement of HPMC.

Hollow Fiber Membrane Modification by Interfacial Polymerization for Organic Solvent Nanofiltration

Hollow fiber (HF) organic solvent nanofiltration (OSN) membranes have recently attracted significant interest in the field of membrane technology. Their popularity stems from comparative advantages, such as high packing density, fouling resistance, and easier scalability for larger applications, unlike flat-sheet/spiral-wound OSN membranes, which may present challenges in these aspects. The combination of interfacial polymerization (IP) and HF configuration has opened up new opportunities for developing advanced membranes with enhanced separation performance that can be tailored for various OSN applications. The objective of this review is to discuss the latest advancements in developing thin film composite (TFC) HF membranes, with a focus on the IP method. Novel materials and processes are discussed in detail, emphasizing the fabrication of greener, interfacially polymerized HF OSN membranes. In addition, the commercial viability and limitations of TFC HF membranes are highlighted, providing perspectives on future research directions.

Biomaterial/Organic Heterojunction Based Memristor for Logic Gate Circuit Design, Data Encryption, and Image Reconstruction

AbstractBenefiting from powerful logic‐computing, higher packaging density, and extremely low electricity consumption, memristors are regarded as the most promising next‐generation of electric devices and are capable of realizing brain‐like neuromorphic computation. However, the design of emerging circuit devices based on memristors and their potential application in unconventional fields are very meaningful for achieving some tasks that traditional electronic devices cannot accomplish. Herein, a Cu/PEDOT:PSS‐PP:PVDF/Ti structured memristor is fabricated by using the polyvinylidene difluoride (PVDF) dopped biomaterial papaya peel (PP) and organic poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) heterojunction as functional layer, which can be switched among resistive switching, self‐rectification effect, and capacitive behavior by adjusting the voltage bias/scan rate. Through further fitting of the data and simulating interfacial group reactions, this work innovatively proposes a charge conduction mode of device driven by Fowler–Nordheim tunneling, complexation reactions, and PEDOT:PSS pore removal. Finally, the regular logic gate and adder circuits are constructed based on the fabricated memristor, while a fully adder‐based encryption unit is designed to realize data encryption and image reconstruction. This work renders memristor compatible with logic circuits, widening a path toward data encryption and information security.

Scrolling in Supramolecular Gels: A Designer's Guide.

Gelation by small molecules is a topic of enormous importance in catalysis, nanomaterials, drug delivery, and pharmaceutical crystallization. The mechanism by which gelators self-organize into a fibrous gel network is poorly understood. Herein, we describe the crystal structures and gelation properties of a library of bis(urea) compounds and show, via molecular dynamics simulations, how gelator aggregation progresses from a continuous pattern of supramolecular motifs to a homogeneous fiber network. Our model suggests that lamellae with asymmetric surfaces scroll into uniform unbranched fibrils, while sheets with symmetric surfaces undergo stacking to form crystals. The self-assembly of asymmetric lamellae is associated with specific molecular features, such as the presence of narrow and flexible end groups with high packing densities, and likely represents a general mechanism for the formation of small-molecule gels.

Reducing anisotropy of rhombohedral Bi-rich phase for high-performance Ag-alloyed Sn–Bi low-temperature solders

The rhombohedral structure is with anisotropic properties, leading to brittle mechanical properties. However, it is one of the major constituent phases, the (Bi) phase, in the Sn–Bi-based low-temperature solders, which is demanding in the electronic industry for reducing the soldering temperature and alleviating the warpage in high-density fine-pitch electronic packaging. Herein, we proposed a high-performance Ag-alloyed Sn–Bi (SBA) low-temperature solder by reducing the fraction and, more importantly, the anisotropy of the (Bi) phase. We found that the (Bi) phase exhibited considerable solubility for Ag and Sn, even after thermal aging, without any nanoprecipitates as confirmed with both CALPHAD-type thermodynamic modeling and high-resolution TEM. The solution effects of Ag and Sn in the (Bi) phase is elaborated based on in situ nano-indentation, EPMA compositional analyses, EBSD characterizations, and ab initio calculations. The presence of Ag and Sn in the (Bi) phases resulted in both solid solution hardening and softening effects, depending on the Schmid factor of the grain. As a result, in (Bi) polycrystals, alloying could effectively mitigate the anisotropic mechanical properties of the (Bi) phase and facilitated a more uniform dispersion of forces exerted among (Bi) grains in all orientations. Consequently, the designed SBA solder exhibited superior mechanical properties, e.g., an ultimate tensile strength (UTS) of 55 MPa, elongation of 46%, and toughness of 20.6 × 106 J/m3 at a strain rate of 0.0005 s−1. This understanding opens the door for enhanced rhombohedral phase in alloy design for various applications.

Assembly and Alignment of High Packing Density Carbon Nanotube Arrays Using Lithographically Defined Microscopic Water Features.

High packing density aligned arrays of semiconducting carbon nanotubes (CNTs) are required for many electronics applications. Past work has shown that the accumulation of CNTs at a water-solvent interface can drive array self-assembly. Previously, the confining interface was a large-area, macroscopic feature. Here, we report on the CNT assembly on microscopic water features. Water microdroplets are formed on 10-100 μm wide hydrophilic stripes patterned on a substrate. Exposure to CNTs dispersed in solvent accumulates CNTs at the microdroplet-solvent interface, driving their alignment and deposition at the microdroplet-solvent-substrate contact line. Compared with macroscopic methods in which the contact line uncontrollably moves across the substrate as it is pulled out of the liquids, the hydrophilic patterns and microdroplets allow pinning of the contact line. As CNTs deposit, the contact line self-translates, allowing for dense CNT packing. We realize monolayer CNT arrays aligned within ±3.9° at density of 250 μm-1 and field effect transistors with a high current density of 1.9 mA μm-1 and transconductance of 1.2 mS μm-1 at -0.6 V drain bias and 60 nm channel length.

A High-Density Organic Package Solution to W-band SiGe Flip-Chip Applications

High-density packaging concepts need to be studied to meet the demands from telecommunication and radar applications which require large operational bandwidth and system compactness. In this work, package design of a transmitter SiGe flip-chip with C4 solder ball interface on a multilayer PCB operating around 94 GHz is presented.

Microscale underfill dynamics and void formation of high-density flip-chip packaging: Experiments and simulations

This research focuses on developing high-fidelity experimental and numerical models to analyze microscale underfill dynamics and void formation in high-density flip-chip packaging. Three underfilling scenarios are investigated, namely, point type, I-shaped line type, and L-type line type. The point-type underfilling validates the numerical model against experimental results, while the I-shaped and L-type line-type underfilling explore grid independence, void formation, and critical parameters such as filling position, contact angle, and liquid viscosity. Results indicate that contact angle and viscosity significantly influence filling efficiency and interface evolution. A smaller contact angle accelerates the process, reducing interface jumping motions. Viscous effects are quantified, revealing dimensionless filling time convergence. The use of low-viscosity surrogate fluids enhances numerical simulation efficiency. Sub-bump-sized, bump-sized, and sup-bump-sized voids are observed, identifying three void formation scenarios representing different underfilling flow mechanisms. This study provides insight into microscale flip-chip underfill physics and establishes validated models for next-generation high-density flip-chip products. These models can be further refined and integrated into optimization tools for automated process design, contributing to improved assembly yield and reliability of emerging electronic packages through physics-based understanding and modeling.

Solder-less Fine Pitch Copper-to-Copper Bonding

The industry has been looking to increase pitch scaling through various methods. One of these methods is an alternative to solid-state solder bonding. However, very few processes can compete with solder bonding’s fast speed, low cost, and flexibility. The approach with the biggest potential for connecting fine pitch interconnects in high-density semiconductor packaging is solder-less copper-to-copper direct bonding. There are many benefits to using copper-to-copper direct bonding, including the ability to achieve ultra-fine-pitch (bump pitch 10 μm), higher reliability (both thermo-mechanically and better electromigration behavior), low resistance, as well as the lack of concern for solder hierarchy for multiple reflow. This copper-to-copper direct bonding technology enables a variety of 2.5D/3D advanced packaging architectures and is also suitable for multi-die stacking. In this study, we report the investigation of a direct copper-to-copper bonding methodology and reliability of the bonded components. Our process differs from common hybrid bonding copper-to-copper techniques, in that it is designed for low volume highly complex products. This technology allows a die-to-die and die-to-wafer process using thermocompression bonding under a deoxidizing vapor flow for direct copper-to-copper bonding. The process does not require high temperature oven annealing and can be done in a normal atmospheric environment. The investigated bonding process is ideal for high power, high thermal, high density 3D stacking and high-speed digital communication applications. We demonstrated the bonding procedure using a test vehicle with 40 μm diameter pillars and 80-μm bump pitch. We investigated the effects of bonding force and evaluated joint reliability. Interconnect/bond strength was determined through destructive shear testing and cross-sectional analysis. A scanning electron microscope was used to inspect and examine the bonded joint quality. Finally, completed assemblies were thermal cycled to evaluate degradation of joint strength under induced stress, and resistance measurements were performed to evaluate the electrical performance of the bonded copper joint.

Interfacial reaction of Sn-1.5Ag-2.0Zn low-silver lead-free solder with oriented copper

High density packaging technology reduces the pad size and the number of grains contained in the pad. When the polycrystalline pad turns into a single crystal pad, the grain orientation has an important impact on the formation of the intermetallic compound (IMC) at the interface. The growth of IMC at the interface between the solder and the single-crystal copper substrate is investigated by selecting the prospective Sn-1.5Ag–2Zn as the solder alloy. Sn-1.5Ag-2.0Zn lead-free solder joints soldered with single crystal (111) copper substrate and polycrystalline red copper substrate are reflowed at 250 °C for 5 min. Samples are subsequently aged at 160 °C. The uneven scallop like Cu6Sn5 IMC layer grows rapidly when the alloy solder contacts with the copper substrate. The Cu6Sn5 grain size formed on the surface of single crystal copper is larger than that of polycrystalline copper. Single crystal copper has no grain boundary to block atomic diffusion, which affects grain nucleation and growth. The growth rate of Cu6Sn5 formed by alloy solder and the single crystal (111) copper solder joint after aging treatment at 160 °C for 20 h is about twice that of the polycrystalline copper solder joint. Then it grows slowly with the increase of aging treatment time. The thick layer Cu6Sn5 breaks due to crack diffusion after 600 h of aging treatment, and the thickness of IMC remains at 3.5 μm. Cu5Zn8 generated at the solder and polycrystalline copper solder joint during aging treatment acts as a barrier layer, preventing the solder from contacting the copper substrate and inhibiting the formation of Cu6Sn5. Cu5Zn8 is broken and decomposed after 300 h of aging treatment, and Cu6Sn5 grows rapidly after the barrier layer disappeared. The thickness of Cu6Sn5 is about 2.8 μm. The thickness of IMC of solder joint on single crystal copper is 0.7 μm more than that on polycrystalline copper. After aging treatment, the IMC formed at the interface between alloy solder and single crystal copper has better compactness and basically no pores, while there are obvious pores between IMC grains at the interface between alloy solder and polycrystalline copper, which can predict that the soldering quality of the interface between alloy solder and single crystal copper is better. This will provide application prospects for solder joint interface reliability research.