Micromachines最新文献

{"title":"Effect of Reflow Temperature on Interfacial IMC Growth in Pb-Free/Pb Mixed-Assembly Micro-Solder Joints.","authors":"Yang Xiao, Yifan Bai, Xinyuan He, Qiming Cui, Lijuan Cheng, Rui Yang, Qi Zhang, Yong Wang","doi":"10.3390/mi17091034","DOIUrl":"10.3390/mi17091034","url":null,"abstract":"<p><p>This study examines interfacial intermetallic compound (IMC) growth in Pb-free/Pb mixed assemblies comprising 450 µm SAC305 solder balls and Cu pads printed with a 0.12 mm layer of Sn63Pb37 solder paste. Samples were reflowed at peak temperatures of 200, 220, 240, and 260 °C, with the time above 217 °C fixed at 40 s. Scanning electron microscopy, energy-dispersive X-ray spectroscopy, and electron backscatter diffraction were used to characterize the interfacial composition, morphology, layer thickness, grain size, and kernel average misorientation (KAM). The IMC layer thickened from 1.5 µm at 200 °C to 6.0 µm at 260 °C, while KAM<i>_ave</i> increased from 0.36° to 0.59°. At 220 °C, the IMC thickness changed only slightly to 1.6 µm, accompanied by local Pb and Ag enrichment. At 240 °C, the IMC thickness increased sharply to 4.7 µm and KAM<i>_ave</i> increased to 0.55°, together with larger Cu₆Sn₅ grains and localized coarsening. At 260 °C, the IMC thickness reached 6.0 µm and KAM<i>_ave</i> reached 0.59°, while Pb-rich regions became more pronounced and the Ag content decreased markedly, indicating substantial interfacial solute redistribution and increasingly heterogeneous IMC growth. The results link the reflow temperature to changes in interfacial chemistry, and microstructure and can help define a suitable process window for Pb-free/Pb mixed assembly.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"17 9","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13609102/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149062382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electrolyte-Regulated Ion Accommodation and Microstructural Stability in WO₃ Electrochromic Thin Films.","authors":"Xuefeng Chu, Siming Qiao, Wenhao Ma, Kunjie Lin, Faxin Peng, Xinyuan Zhang, Jie Wu, Haiyang Zhao, Longyu Guo, Huan Wang, Sa Lv, Xiaotian Yang","doi":"10.3390/mi17091033","DOIUrl":"10.3390/mi17091033","url":null,"abstract":"<p><p>Electrochromic tungsten oxide (WO₃) films suffer from gradual performance degradation during repeated ion insertion/extraction processes, while the relationship between electrolyte-dependent ion accommodation and structural stability remains insufficiently understood. Herein, magnetron-sputtered WO₃ thin films were systematically investigated in H₂SO₄, LiClO₄, ZnSO₄, and Al₂(SO₄)₃ electrolytes to clarify the coupling relationship among ion accommodation, electronic structure evolution, microstructural retention, and electrochromic durability. Combined electrochemical measurements with UV-visible spectroscopy, atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and reflected electron energy loss spectroscopy (REELS) reveal that electrolyte chemistry regulates the balance between electrochemical activation and structural tolerance. Highly mobile H⁺ and strongly interacting Al³⁺ ions promote rapid ion transport and enhanced W⁶⁺ reduction but may induce excessive structural perturbation, defect accumulation, and accelerated degradation during cycling. Zn²⁺ exhibits intermediate behavior, whereas Li⁺ enables balanced ion accommodation through reversible W⁶⁺/W⁵⁺ conversion while preserving the WO₃ framework. Consequently, the LiClO₄ electrolyte achieves superior electrochromic performance with an optical modulation of 80.97% and improved cycling stability. These results demonstrate that durable electrochromic behavior is governed not by maximizing ion transport or reduction degree, but by achieving a reversible ion accommodation regime compatible with the structural tolerance of the host framework. This work provides a microstructure-oriented strategy for designing stable WO₃-based electrochromic devices through electrolyte regulation.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"17 9","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13609757/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149062450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecularly Imprinted Polymers for Biosensing: From Synthetic Recognition to Integrated Biointerfaces.","authors":"Giovanna Di Pasquale, Antonino Pollicino","doi":"10.3390/mi17091037","DOIUrl":"10.3390/mi17091037","url":null,"abstract":"<p><p>Molecularly imprinted polymers (MIPs) are synthetic receptors with cavities shaped around a template, combining antibody-like selectivity with chemical, thermal, and mechanical robustness; low cost; and reusability. This Review examines recent advances in MIP-based biosensing, from bulk materials to thin-film, nanostructured, surface-imprinted, and epitope-imprinted architectures designed to improve site accessibility and performance in complex biofluids. We connect polymer chemistry and interface design to molecular recognition and electrochemical, optical, and mass-sensitive transduction. Applications range from small molecules, proteins, nucleic acids, and viruses to whole cells, encompassing miniaturized, wearable, and point-of-care formats. Particular attention is devoted to design assisted by computational methods and machine learning, as well as to the challenges of reproducibility, standardization, metrology, and sustainability that still limit translation. Rather than universal substitutes for antibodies, MIPs are presented as programmable biointerfaces that integrate molecular recognition, signal transduction, device engineering, and the design of low-environmental-impact materials.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"17 9","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13609329/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149062337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Reconfigurable Electro-Optic Photonic Integrated Circuit Architecture.","authors":"Paulo Lourenço, André Moreira, Ernesto Velázquez, Alessandro Fantoni","doi":"10.3390/mi17091035","DOIUrl":"10.3390/mi17091035","url":null,"abstract":"<p><p>In this work, we present the design and numerical validation of a reconfigurable electro-optic photonic integrated circuit architecture for dynamic 1 × 4 optical routing, based on electro-optic phase shifters and a chain of cascaded multimode interference structures, and implemented in an amorphous silicon platform. By exploiting recent developments in symmetry-engineered silicon photonics to enable phase control in a platform compatible with complementary metal-oxide-semiconductor fabrication requirements, this approach addresses the increasing demand for ultra-fast, compact and energy efficient reconfigurable photonic integrated circuits. The photonic circuit design bases its functionality on self-imaging theory and has been optimized through simulations implementing the beam propagation method, while optical performance and electro-optical behavior have been validated through finite difference time-domain simulations and multiphysics modeling. The numerical results obtained confirm the operational performance of the individual building blocks and demonstrate the proposed architecture as being able to perform as a reconfigurable electro-optic platform and provide the dynamic 1 × 4 optical routing. Hence, this architecture provides a scalable platform for reconfigurable silicon photonics, complementary metal-oxide-semiconductor compatible, and the fabrication-ready layout establishes a practical path to experimental validation and future reconfigurable photonic integrated circuits.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"17 9","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13609311/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149062493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Solid Dispersion Characteristics of an Oscillatory Microfluidic Mixer: An Experimental and Numerical Investigation.","authors":"Yao Lu, Haixuan Sun, Yifan Qin","doi":"10.3390/mi17091036","DOIUrl":"10.3390/mi17091036","url":null,"abstract":"<p><p>Point-of-care (POC) diagnostic testing based on microfluidic technology plays an important role in coagulation management. Its precision is, however, limited by the inefficient mixing between blood and solid activators in laminar microfluidic flow. In this study, a novel micromixer incorporating periodic oscillatory flow was developed to enhance blood-activator mixing. A computational fluid dynamic (CFD) model was established to investigate the microscale hydrodynamic characteristics and solid dispersion behavior in the oscillatory multiphase flow system. The numerical predictions were validated against tracer mixing experiments. Sample calculations for the air-liquid-solid flow system demonstrated that the initial loading position of activator particles significantly affected the dispersion efficiency due to the spatial variation in the radial velocity field. Compared with the center-initialized case, the solid dispersion level in the corner-initialized case decreased by approximately 42% after two oscillation cycles. Furthermore, the influence mechanism of oscillation period on solid dispersion was clarified through multi-physics coupling analysis. This study provided new insights into solid-liquid mixing in oscillatory microfluidic systems and established an effective CFD-based framework for optimizing microdevice design and operating conditions.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"17 9","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13609804/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149062350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Two-Dimensional, Vision-Based Measurement for Experimental Characterization of Planar Compliant Mechanisms: A Critical Review and Uncertainty-Aware Framework.","authors":"Rohan R Ozarkar, Nilesh P Salunke, Prajitsen G Damle, Shakeelur Raheman, Khursheed B Ansari","doi":"10.3390/mi17091031","DOIUrl":"10.3390/mi17091031","url":null,"abstract":"<p><p>In planar compliant mechanisms, single-input dual-output (SIDO) displacement amplifiers driven by piezoelectric actuators are frequently used in precision positioning, micro/nano manipulation, and biomedical microdevices. Accurate experimental verification of these mechanisms remains challenging because traditional contact sensors can add excess stiffness and impact the structure's normal behavior, and single-axis interferometers cannot measure multiple points simultaneously. In contrast, 2D vision-based measurement offers a non-contact alternative capable of capturing full planar motion and synchronized displacement tracking within a single image frame. This paper reviews the literature on camera calibration, homography-based planar reconstruction, sub-pixel edge extraction, vision-based characterization of compliant mechanisms, and benchmarking of vision systems against laser interferometers and coordinate measuring machines (CMMs). In the review, the SIDO-CDAM developed by Ozarkar et al. based on the Instantaneous Center Building Block (IC-BB) approach has been chosen as the target characterization system. The reviewed studies confirm that the major technical components needed for a high-precision 2D vision framework have been independently validated. However, there seems to be a lack of an integrated framework designed for synchronized dual-output SIDO-CDAM characterization. To overcome this gap, a seven-layer 2D vision-based characterization framework is proposed for scalable inspection of prototype-scale and MEMS-scale compliant mechanisms.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"17 9","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13609846/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149062461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Frontier Advances in Wind-Driven Triboelectric Nanogenerators for Realistic Wind Environments: Scenario-Oriented Architecture Design, System Integration, and Critical Assessment.","authors":"Mingkang Zhu, Jing Wu, Guangxi Li, Zikang Li, Hao Liu, Kaicheng Yu, Sheng Zhang, Chao Wang","doi":"10.3390/mi17091024","DOIUrl":"10.3390/mi17091024","url":null,"abstract":"<p><p>Triboelectric nanogenerators (TENGs) offer promising opportunities for distributed wind energy harvesting owing to their low-speed responsiveness, structural flexibility, and adaptability to non-stationary airflow. This review examines wind-driven TENGs from the perspective of realistic wind-field constraints, focusing on three representative scenarios: urban micro-winds, offshore wind-wave environments, and low-altitude complex flows. Scenario-specific advances in device architectures, materials and interfaces, environmental protection, power management, and system integration are systematically reviewed. Representative devices are further quantitatively compared in terms of wind-speed range, activation threshold, electrical output, power density, durability, and system-level energy delivery. Particular attention is given to inconsistent definitions of cut-in wind speed, output normalization, electrical loading, and validation conditions that limit cross-study comparison. Field-validation evidence is assessed from controlled laboratory tests to long-term field operation. Key challenges involving usable regulated energy, environmental reliability, lifetime prediction, array scaling, sustainability, and deployment economics are critically discussed. Finally, five grand challenges with actionable milestones are proposed to facilitate the transition of wind-driven TENGs from laboratory prototypes toward deployable distributed micro-energy systems.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"17 9","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13609712/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149062536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Asymmetric Flow Dynamics in a Pneumatically Actuated Polydimethylsiloxane (PDMS) Micropump: Numerical Simulation and Experimental Validation.","authors":"Pei-Pei Hsu, Jr-Lung Lin","doi":"10.3390/mi17091027","DOIUrl":"10.3390/mi17091027","url":null,"abstract":"<p><p>This study presents a comprehensive numerical and experimental investigation on a pneumatically actuated polydimethylsiloxane (PDMS) micropump integrated with passive check valves (PCVs). Advanced three-dimensional (3D) fluid-structure interaction (FSI) simulations were conducted to capture the nonlinear large deformation of the membrane and elucidate the Newtonian flow dynamics. The maximum deformation calculated by the simulations was compared with the theoretical Timoshenko formula, demonstrating excellent agreement across the entire pressure range (3.0-100.0 kPa). The 3D FSI simulations revealed a considerable asymmetry in the flow dynamics between the suction and compression phases. Notably, at applied pressures exceeding 20.0 kPa, the discharge volume substantially outweighed the suction one. To characterize both the ideal and practical volumetric flow rates, curve-fitting analyses revealed that both the simulation and experimental data follow a consistent 1/3-power-law relationship with respect to the applied pressure. Experimentally, the micropump achieved a maximum volumetric flow rate of 2.6 mL/min at 70.0 kPa and 12.0 Hz. Furthermore, the micropump demonstrated a peak pumping efficiency of 56.95% at 35.0 kPa and 10.0 Hz relative to the ideal numerical baseline. By bridging idealized numerical bounds with experimental realities, this validated framework offers a robust predictive tool for optimizing flow asymmetry and pumping efficiency in advanced microfluidic systems.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"17 9","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13609855/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149062134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Laser Ultrasonic Detection and Signal Enhancement of Internal Microdefects in LPBF Ti6Al4V with Anisotropic Microstructure: Simulations and Experiments.","authors":"Xingyu Zhou, Jia Xie, Yixuan He, Ping Hu","doi":"10.3390/mi17091025","DOIUrl":"10.3390/mi17091025","url":null,"abstract":"<p><p>Laser Powder Bed Fusion (LPBF) has revolutionized high-end manufacturing, particularly in aerospace and biomedical fields. However, internal defects such as pores, cracks, and inclusions compromise the structural integrity and service reliability of LPBF components. Laser ultrasonics, a non-contact, broadband non-destructive testing (NDT) method, offers a promising solution for detecting and characterizing these defects. This study systematically investigated laser ultrasonic testing technology for LPBF-fabricated Ti6Al4V using a combined approach of physics-driven simulation modeling and experimental validation. To accurately model material anisotropy, a finite element model was developed that integrated Voronoi algorithm-generated polycrystalline microstructures with orientation-dependent elastic tensors, providing a comprehensive representation of the material's microstructural heterogeneity. Simulation results revealed that while sub-100-μm defects yield weak ultrasonic scattering signals, the Synthetic Aperture Focusing Technique (SAFT) markedly improves the detection and imaging performance for such small-scale defects. Experimental validation using a laser ultrasonic system identified a 90 μm internal defect in the LPBF Ti6Al4V specimen, though a 75 μm defect was undetectable. This highlights the need for enhanced sensitivity. A signal processing method combining time-truncation principal component analysis (PCA) with targeted noise reduction and SAFT was proposed to reduce high-frequency noise and improve high-resolution imaging, enhancing defect detection accuracy. This study provides theoretical foundations and technical support for high-precision defect detection in metal additive manufacturing components, with significant implications for quality control in high-end equipment manufacturing.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"17 9","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13609852/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149062561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative Performance of Electrode Models for Thickness-Shear AT-Cut Quartz Resonators.","authors":"Hang Chen, Xin Fu, Wanli Yang, Chao Zhan, Feng Xiong, Xiaohu Wang, Hongping Hu, Yuantai Hu","doi":"10.3390/mi17091023","DOIUrl":"10.3390/mi17091023","url":null,"abstract":"<p><p>In this study, we compare four electrode models, i.e., solid model, added mass model, thin-film model, and a combining model of thin-film with added mass, for a 76.8 MHz AT-cut quartz resonator. Relative to the high-fidelity solid electrode benchmark, the combining model accurately captures the thickness-shear mode but overestimates displacement confinement due to mass loading and boundary effects. The thin-film model fails to replicate practical device states by ignoring mechanical mass and stiffness. In contrast, the added mass model optimally balances fidelity and efficiency, matching the benchmark's frequency and resistance predictions with a 43% reduction in computation time. Parametric studies further indicate that cut angle deviations (33°~37°) alter equivalent shear stiffness, while electrode mass variations (mass coefficient 0.99~1.02) modify vibrational inertia. Both of them are critical for frequency tuning. Our findings clarify the scope and limitations of these strategies, guiding high-precision simulations and designs for high-frequency resonators.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"17 9","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13609347/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149062331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}