Micromachines最新文献

{"title":"Directional Fluidity of Dense Emulsion Activated by Transverse Wedge-Shaped Microroughness.","authors":"Giacomo Guastella, Daniele Filippi, Davide Ferraro, Giampaolo Mistura, Matteo Pierno","doi":"10.3390/mi16030335","DOIUrl":"10.3390/mi16030335","url":null,"abstract":"<p><p>The handling and fluidization of amorphous soft solids, such as emulsions, foams, or gels, is crucial in many technological processes. This is generally achieved by applying mechanical stress that overcomes a critical threshold, known as yield stress, below which these systems behave as elastic solids. However, the interaction with the walls can facilitate the transition from solid to fluid by activating rearrangements of the fluid constituents close to the wall, resulting in increased fluidity of the system up to distances greater than the spatial scale of the rearrangements. We address the impact of wedge-shaped microroughness on activating the fluidization of emulsion droplets in pressure-driven flow through microfluidic channels. We realize the micro wedges by maskless photolithography to texture one wall of the channel and measure the velocity profiles for flow directed accordingly and against the increasing ramp of the wedge-shaped grooves. We report the enhancement of the emulsion flow in the direction of the climbing ramp of the wedge activated by increasing the magnitude of the pressure gradient. A gain for the volumetric flow rate is registered with respect to the opposite direction as being to 30%, depending on the pressure drop.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"16 3","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11946712/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143720271","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":"Performance Degradation of Ga₂O₃-Based X-Ray Detector Under Gamma-Ray Irradiation.","authors":"Xiao Ouyang, Silong Zhang, Tao Bai, Zhuo Chen, Yuxin Deng, Leidang Zhou, Xiaojing Song, Hao Chen, Yuru Lai, Xing Lu, Liang Chen, Liangliang Miao, Xiaoping Ouyang","doi":"10.3390/mi16030339","DOIUrl":"10.3390/mi16030339","url":null,"abstract":"<p><p>X-ray response performances of a p-NiO/<i>β</i>-Ga₂O₃ hetero-junction diode (HJD) X-ray detector were studied before and after γ-ray irradiation at -200 V, with a total dose of 13.5 kGy(Si). The response performances of the HJD X-ray detector were influenced by the trap-assistant conductive process of the HJD under reverse bias, which exhibited an increasing net (response) current, nonlinearity, and a long response time. After irradiation, the Poole-Frenkel emission (PFE) dominated the leakage current of HJDs due to the higher electric field caused by the increased net carrier concentration of <i>β</i>-Ga₂O₃. This conductive process weakened the performance of the HJD X-ray detector in terms of sensitivity, output linearity, and response speed. This study provided valuable insights into the radiation damage and performance degradation mechanisms of Ga₂O₃-based radiation detectors and offered guidance on improving the reliability and stability of these radiation detectors.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"16 3","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11944653/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143720262","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":"Efficient Particle Capture and Release Method for DNA Library Preparation on Microfluidics.","authors":"Zihan Song, Yihui Wu, Fengfeng Shu, Xiao Lv, Junyu Dong, Huan Li","doi":"10.3390/mi16030332","DOIUrl":"10.3390/mi16030332","url":null,"abstract":"<p><p>To address the issues of agglomeration during magnetic particle capture and the incomplete release of these particles during reuse in microfluidic chips for library preparation, a microchamber was utilized to enhance the dispersion area for magnetic particle capture. Additionally, the release of magnetic particles was achieved through the synergistic action of flow field and magnetic field. The simulation results indicated that as the inlet flow velocity varied from 0.02 m/s to 0.16 m/s and the magnet spacing ranged from 1.2 mm to 1.8 mm, the coverage of magnetic particles in the microchamber increased from 17.29% to 63.59%. Meanwhile, the magnetic particle capture rate decreased from 100% to 35.2%. These processes were further validated through experimental methods. During the release process, the trajectory of magnetic particles under the synergistic effect of flow field and magnetic field aligned with expectations. The captured magnetic particles were released from the microchamber within 12 s, achieving a release rate of 100%.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"16 3","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11946811/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143720275","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 Pathway for the Integration of Novel Ferroelectric Thin Films on Non-Planar Photonic Integrated Circuits.","authors":"Enes Lievens, Kobe De Geest, Ewout Picavet, Liesbet Van Landschoot, Henk Vrielinck, Gilles Freddy Feutmba, Hannes Rijckaert, Klaartje De Buysser, Dries Van Thourhout, Peter Bienstman, Jeroen Beeckman","doi":"10.3390/mi16030334","DOIUrl":"10.3390/mi16030334","url":null,"abstract":"<p><p>The heterogeneous integration of ferroelectric thin films on silicon- or silicon nitride-based platforms for photonic integrated circuits plays a crucial role in the development of nanophotonic thin film modulators. For this purpose, an ultrathin seed film was recently introduced as an integration method for ferroelectric thin films such as BaTiO₃ and Pb(Zr,Ti)O₃. One issue with this self-orienting seed film is that for non-planarized circuits, it fails to act as a template film for the thin films. To circumvent this problem, we propose a method of planarization without the need for wafer-scale chemical mechanical polishing by using hydrogen silsesquioxane as a precursor to forming amorphous silica, in order to create an oxide cladding similar to the thermal oxide often present on silicon-based platforms. Additionally, this oxide cladding is compatible with the high annealing temperatures usually required for the deposition of these novel ferroelectric thin films (600-800 °C). The thickness of this silica film can be controlled through a dry etch process, giving rise to a versatile platform for integrating nanophotonic thin film modulators on a wider variety of substrates. Using this method, we successfully demonstrate a hybrid BaTiO₃-Si ring modulator with a high Pockels coefficient of rwg=155.57±10.91 pm V^-1 and a half-wave voltage-length product of VπL=2.638±0.084 V cm, confirming the integration of ferroelectric thin films on an initially non-planar substrate.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"16 3","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11945360/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143719629","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 Review on Micro-Watts All-Digital Frequency Synthesizers.","authors":"Venkadasamy Navaneethan, Boon Chiat Terence Teo, Annamalai Arasu Muthukumaraswamy, Xian Yang Lim, Liter Siek","doi":"10.3390/mi16030333","DOIUrl":"10.3390/mi16030333","url":null,"abstract":"<p><p>This paper reviews recent developments in highly integrated all-digital frequency synthesizers suitable to deploy in low-power internet-of-things (IoT) applications. This review sets low power consumption as a key criterion for exploring the all-digital frequency synthesizer implemented in CMOS fabrication technology. The alignment with mainstream CMOS technology offers high-density, comprehensive, robust signal processing capability, making it very suitable for all-digital phase-locked loops to harvest that capacity, and it becomes inevitable. This review includes various divider-less low-power frequency synthesizers, including all-digital phase-locked loops (ADPLL), all-digital frequency-locked loops (ADFLL), and hybrid PLLs. This paper also discusses the latest architectural developments for ADPLLs to lead to low-power implementation, such as DTC-assisted TDC, embedded TDC, and various levels of hybridization in ADPLLs.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"16 3","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11944421/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143719754","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":"Spectral and Microscopic Behavior of Type III Femtosecond Fiber Bragg Gratings at High Temperatures.","authors":"Matilde Sosa, Maxime Cavillon, Thomas Blanchet, Matthieu Lancry, Guillaume Laffont","doi":"10.3390/mi16030331","DOIUrl":"10.3390/mi16030331","url":null,"abstract":"<p><p>Fiber Bragg gratings are key components for optical fiber sensing applications in harsh environments. Microvoids, or so-called type III fiber Bragg gratings, fabricated using femtosecond lasers and the point-by-point technique, were characterized at high temperatures (>1100 °C). For this purpose, we monitored the spectral characteristics of the grating, as well as the evolution of the microstructure during a 30 min isochronal annealing process. This study allowed us to correlate the behavior of the microvoids with the spectral performances (amplitude, wavelength drift) of the sensors at very high temperatures. As the grating signal is being lost at increasing temperatures (above 1125 °C), the periodic array of microvoids becomes disordered and deformed, ultimately losing its periodic spacing.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"16 3","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11944549/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143720436","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":"Multilevel Multimodal Physical Unclonable Functions by Laser Writing of Silicon Carbide Color Centers.","authors":"Yuxing Ma, Yue Qin, Hao Guo, Ye Tian, Lishuang Liu","doi":"10.3390/mi16030329","DOIUrl":"10.3390/mi16030329","url":null,"abstract":"<p><p>Information security serves as the cornerstone for ensuring the stable development of today's highly digitized era. As cryptographic primitives with high security and robust encryption capabilities, physical unclonable functions (PUFs) are recognized as one of the critical solutions to address information leakage issues. However, the encoding of PUFs often relies on the inherent properties of materials, which limits the potential for further enhancement of their encoding capacity (EC). In this study, we introduce a four-level encoding scheme by leveraging the stochastic characteristics of free radical chemical reactions and energy deposition in the fabrication process of silicon carbide (SiC) color centers. A multilevel multimodal PUF (MMPUF) encoding strategy (ES) for flexible substrates with high EC, low cost, and simple and fast readout was constructed. The spatially random distribution of SiC and silicon vacancy (V_si) color-center concentrations as well as the offsets of the laser pyrolysis position along the <i>X</i>- and <i>Y</i>-axes are four independent physical properties that ensure the encoding performance of the PUF, achieving a high encoding capacity of 2^4×10×10 and secure, stable, and unclonable encoding. Furthermore, the integration of the PUF tags with the products through a doping manufacturing process, rather than simple attachment, enhances the security and practicality of the anti-counterfeiting system. The proposed encoding hierarchy based on the offsets provides a novel encoding solution for improving PUF EC.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"16 3","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11946732/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143720294","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":"Application Characteristics of Ultra-Fine 15 μm Stainless Steel Wires: Microstructures, Electrical Fatigue, and Ball Formation Mechanisms.","authors":"Hsiang-Chi Yang, Fei-Yi Hung, Bo-Ding Wu, Yi-Tze Chang","doi":"10.3390/mi16030326","DOIUrl":"10.3390/mi16030326","url":null,"abstract":"<p><p>Stainless steel wires exhibit excellent mechanical properties and are widely used in engineering applications. This study fabricates 15 μm stainless steel wires for potential integration into wire bonding technology for electronic packaging. The research explores the microstructural characteristics, electrical conduction mechanisms, and ball formation behavior of ultra-fine stainless-steel wires to assess their feasibility for wire bonding applications. Results indicate that both 15 μm and 30 μm stainless steel wires exhibit elongated grains with outstanding tensile strength and hardness. Compared to the 30 μm wires, the 15 μm wires undergo more pronounced work hardening, leading to higher tensile strength and resistance. This study investigates the differences between vacuum and electrified annealing processes to address the work hardening and ductility issues in stainless steel wires. Results confirm that the hardness of the original wire significantly decreases after vacuum annealing at 780 °C for 15 min. Furthermore, using the derived equation, T=IV2.3085×10-3+25, the annealing temperature of 780 °C is converted into an equivalent current, and electrify annealing is conducted under a condition of 0.08 A for 15 min. The annealed wires exhibit a softening effect and enhance ductility. Furthermore, due to stored deformation energy and recrystallization effects, the electrical fatigue life of 15 μm stainless steel wires is approximately 300 cycles. After electrifying annealing, the base microstructure becomes more homogeneous due to thermal effects, reducing fatigue life to around 150 cycles. However, due to the softening effect, the annealed wires make the EFO process easier and minimize solidification segregation in the free air ball (FAB) microstructure, demonstrating their potential for electronic packaging applications.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"16 3","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11946405/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143720049","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":"Design, Fabrication, and Application of Large-Area Flexible Pressure and Strain Sensor Arrays: A Review.","authors":"Xikuan Zhang, Jin Chai, Yongfu Zhan, Danfeng Cui, Xin Wang, Libo Gao","doi":"10.3390/mi16030330","DOIUrl":"10.3390/mi16030330","url":null,"abstract":"<p><p>The rapid development of flexible sensor technology has made flexible sensor arrays a key research area in various applications due to their exceptional flexibility, wearability, and large-area-sensing capabilities. These arrays can precisely monitor physical parameters like pressure and strain in complex environments, making them highly beneficial for sectors such as smart wearables, robotic tactile sensing, health monitoring, and flexible electronics. This paper reviews the fabrication processes, operational principles, and common materials used in flexible sensors, explores the application of different materials, and outlines two conventional preparation methods. It also presents real-world examples of large-area pressure and strain sensor arrays. Fabrication techniques include 3D printing, screen printing, laser etching, magnetron sputtering, and molding, each influencing sensor performance in different ways. Flexible sensors typically operate based on resistive and capacitive mechanisms, with their structural designs (e.g., sandwich and fork-finger) affecting integration, recovery, and processing complexity. The careful selection of materials-especially substrates, electrodes, and sensing materials-is crucial for sensor efficacy. Despite significant progress in design and application, challenges remain, particularly in mass production, wireless integration, real-time data processing, and long-term stability. To improve mass production feasibility, optimizing fabrication processes, reducing material costs, and incorporating automated production lines are essential for scalability and defect reduction. For wireless integration, enhancing energy efficiency through low-power communication protocols and addressing signal interference and stability are critical for seamless operation. Real-time data processing requires innovative solutions such as edge computing and machine learning algorithms, ensuring low-latency, high-accuracy data interpretation while preserving the flexibility of sensor arrays. Finally, ensuring long-term stability and environmental adaptability demands new materials and protective coatings to withstand harsh conditions. Ongoing research and development are crucial to overcoming these challenges, ensuring that flexible sensor arrays meet the needs of diverse applications while remaining cost-effective and reliable.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"16 3","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11945720/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143720180","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":"Composite Magnetic Filaments: From Fabrication to Magnetic Hyperthermia Application.","authors":"Athanasios Alexandridis, Apostolos Argyros, Pavlos Kyriazopoulos, Ioannis Genitseftsis, Nikiforos Okkalidis, Nikolaos Michailidis, Makis Angelakeris, Antonios Makridis","doi":"10.3390/mi16030328","DOIUrl":"10.3390/mi16030328","url":null,"abstract":"<p><p>The printing of composite magnetic filaments using additive manufacturing techniques has emerged as a promising approach for biomedical applications, particularly in bone tissue engineering and magnetic hyperthermia treatments. This study focuses on the synthesis of nanocomposite ferromagnetic filaments and the fabrication of bone tissue scaffolds with time-dependent properties. Three classes of polylactic acid-based biocompatible polymers-EasyFil, Tough and Premium-were combined with magnetite nanoparticles (Fe₃O₄) at concentrations of 10 wt% and 20 wt%. Extruded filaments were evaluated for microstructural integrity, printed dog-bone-shaped specimens were tested for elongation and mechanical properties, and cylindrical scaffolds were analyzed for magnetic hyperthermia performance. The tensile strength of EasyFil polylactic acid decreased from 1834 MPa (0 wt% Fe₃O₄) to 1130 MPa (-38%) at 20 wt% Fe₃O₄, while Premium polylactic acid showed a more moderate reduction from 1800 MPa to 1567 MPa (-13%). The elongation at break was reduced across all samples, with the highest decrease observed in EasyFil polylactic acid (from 42% to 26%, -38%). Magnetic hyperthermia performance, measured by the specific absorption rate, demonstrated that the 20 wt% Fe₃O₄ scaffolds achieved specific absorption rate values of 2-7.5 W/g, depending on polymer type. Our results show that by carefully selecting the right thermoplastic material, we can balance both mechanical integrity and thermal efficiency. Among the tested materials, Tough polylactic acid composites demonstrated the most promising potential for magnetic hyperthermia applications, providing optimal heating performance without significantly compromising scaffold strength. These findings offer critical insights into designing magnetic scaffolds optimized for tissue regeneration and hyperthermia-based therapies.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"16 3","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11946111/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143720218","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}