Micromachines最新文献

{"title":"The Effect of MoS₂ and Si₃N₄ in Surface Plasmon Resonance Biosensors for HIV DNA Hybridization Detection: A Numerical Study.","authors":"Talia Tene, Diana Coello-Fiallos, María de Lourdes Palacios Robalino, Fabián Londo, Cristian Vacacela Gomez","doi":"10.3390/mi16030295","DOIUrl":"10.3390/mi16030295","url":null,"abstract":"<p><p>This study presents a numerical investigation of surface plasmon resonance (SPR) biosensors incorporating silicon nitride (Si₃N₄) and molybdenum disulfide (MoS₂) for HIV DNA hybridization detection. By optimizing the thickness of Ag and Si₃N₄ and the number of MoS₂ layers, two configurations, Sys₂ (Ag-Si₃N₄) and Sys₃ (Ag-Si₃N₄-MoS₂), were selected for comparative analysis. Performance metrics, including the resonance angle shift, sensitivity, detection accuracy, and quality factor, demonstrated that Sys₂ achieved the highest sensitivity of 210.9°/RIU and an enhanced figure of merit (86.98 RIU^-1), surpassing state-of-the-art SPR sensors. Although Sys₃ exhibited a lower sensitivity of 158.1°/RIU due to MoS₂-induced optical losses, it provided a lower limit of detection, suggesting a trade-off between sensitivity and spectral broadening. Compared to previous SPR biosensors, the proposed configurations achieve superior sensitivity while maintaining stability and selectivity, positioning them as promising candidates for next-generation nucleic acid detection platforms.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"16 3","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11946481/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143720483","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 MEMS Pirani Vacuum Gauge Based on Porous Silicon.","authors":"Yuzhe Lin, Zichao Zhang, Jifang Tao, Lianggong Wen","doi":"10.3390/mi16030296","DOIUrl":"10.3390/mi16030296","url":null,"abstract":"<p><p>Vacuum gauges based on Micro-Electro-Mechanical System (MEMS) technology have the advantages of small size, high reliability, and low cost, so they are widely used in semiconductor, chemical, laboratory, and aerospace. In this paper, a high-reliability MEMS Pirani vacuum gauge based on a porous silicon platform is designed, fabricated, and characterized. The repeatability within 4~10⁵ Pa has been tested. The porous silicon acting as a support material achieved a porosity of 68% and a thermal conductivity of 3.5 W/(m·K), and the surface morphology of the porous silicon is smooth. The proposed MEMS Pirani vacuum gauge containing no suspended thin-film structures has good mechanical stability and is unaffected by mechanical shock and vibration in operation.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"16 3","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11946229/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143720170","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":"The Strength of Ti-6AL-4V Investigated Using Micro-Pillars.","authors":"Rayan B M Ameen, Dilveen W Mohammed, Yu-Lung Chiu, Ian P Jones","doi":"10.3390/mi16030293","DOIUrl":"10.3390/mi16030293","url":null,"abstract":"<p><p>Focused Ion Beam (FIB) has been used to create single α-β colony micro-pillars from a polycrystalline commercial Ti-6Al-4V (Ti-64) sample. Each pillar was selected to have either a single alpha phase, a single beta phase, or two α lamella separated by a thin β phase filet. Then, utilizing a diamond flat tip as a compression platen, uniaxial micro-compression tests were performed on the single crystal α and β pillars as well as a tri-crystal α/β/α pillar using a nano-indenter. Then, utilizing a diamond flat tip as a compression platen, uniaxial micro-compression tests were performed on the single crystal alpha and beta pillars as well as a tri-crystal α/β/α pillar using a nano-indenter. Through the use of Electron Back Scattering Diffraction (EBSD) to choose the crystal orientation along the micro-pillar, three distinct unique slip systems have been selectively triggered by maximizing the Schmid factor for each system. The potential to localize a single crystal volume that can be characterized after deformation is one benefit of the micro-compression approach over traditional mechanical testing. The sample strengths compare well with published data. The mechanical properties of the α-β colonies and the single α and β phases have been compared in order to elucidate the role of the α/β interfaces in determining the critical resolved shear stress.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"16 3","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11944709/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143720491","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":"Low Capillary Elastic Flow Model Optimization Using the Lattice Boltzmann Method and Non-Dominated Sorting Genetic Algorithm.","authors":"Yaqi Hou, Wei Zhang, Jiahua Hu, Feiyu Gao, Xuexue Zong","doi":"10.3390/mi16030298","DOIUrl":"10.3390/mi16030298","url":null,"abstract":"<p><p>In simulations of elastic flow using the lattice Boltzmann method (LBM), the steady-state behavior of the flow at low capillary numbers is typically poor and prone to the formation of bubbles with inhomogeneous lengths. This phenomenon undermines the precise control of heat transfer, mass transfer, and reactions within microchannels and microreactors. This paper establishes an LBM multiphase flow model enhanced by machine learning. The hyperparameters of the machine learning model are optimized using the particle swarm algorithm. In contrast, the non-dominated sorting genetic algorithm (NSGA-II) is incorporated to optimize bubble lengths and stability. This results in a coupled multiphase flow numerical simulation model that integrates LBM, machine learning, and the particle swarm algorithm. Using this model, we investigate the influence of elastic flow parameters on bubble length and stability in a T-shaped microchannel. The simulation results demonstrate that the proposed LBM multiphase flow model can effectively predict bubble elongation rates under complex conditions. Furthermore, multi-objective optimization determines the optimal gas-liquid two-phase inlet flow rate relationship, significantly mitigating elastic flow instability at low capillary numbers. This approach enhances the controllability of the elastic flow process and improves the efficiency of mass and heat transfer.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"16 3","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11945988/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143720240","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 of Metamaterial Sensor for Non Destructive Testing of Aircraft Composite Skin Damage.","authors":"Zhaoxuan Zhu, Rongqing Kang, Kaiyu Qin","doi":"10.3390/mi16030284","DOIUrl":"10.3390/mi16030284","url":null,"abstract":"<p><p>The detection of aircraft skin is an important part of the process of aircraft design, manufacturing, and application. This paper proposes a metamaterial sensor for non-destructive detection of aircraft composite skin damage. Firstly, Using the perturbation theory, an electromagnetic nondestructive detection model of aircraft composite skin is established. Then, according to the plasmon theory, a nested multi-layer complementary split resonant ring (CSRR) metamaterial sensor is designed. Simulation using the high frequency structure simulator (HFSS), it shows that it can effectively detect defect with diameters of 2 mm and above and burial depth within 3 mm. Finally, the physical test is carried out, and the 10 mm diameter defect in the aircraft composite skin sample can be detected.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"16 3","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11946658/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143720158","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 Method for Fabricating Cavity-SOI and Its Verification Using Resonant Pressure Sensors.","authors":"Han Xue, Xingyu Li, Yulan Lu, Bo Xie, Deyong Chen, Junbo Wang, Jian Chen","doi":"10.3390/mi16030297","DOIUrl":"10.3390/mi16030297","url":null,"abstract":"<p><p>Cavity silicon on insulator (Cavity-SOI) offers significant design flexibility for microelectromechanical systems (MEMS). Notably, the shape and depth of the cavity can be tailored to specific requirements, facilitating the realization of intricate multi-layer structural designs. The novelty of the proposed fabrication methodology is manifested in its employment of a micromachining process flow, which integrates dry etching, wafer level Au-Si eutectic bonding, and chemical mechanical polishing (CMP) to create Cavity-SOI. This innovative approach substantially mitigates the complexity of fabrication, and the implementation of wafer-level gold-silicon eutectic bonding and vacuum packaging can be achieved, representing a distinct advantage over conventional methods. To evaluate the technical viability, a MEMS resonant pressure sensor (RPS) was designed. Experimental findings demonstrate that during the formation of Cavity-SOI, dry etching can accurately fabricate cavities of predefined dimensions, wafer-level Au-Si eutectic bonding can achieve efficient sealing, and CMP can precisely regulate the depth of cavities, thus validating the feasibility of the Cavity-SOI formation process. Additionally, when implementing Cavity-SOI in the fabrication of MEMS RPS, it enables the spontaneous release of resonators, effectively circumventing the undercut and adhesion issues commonly encountered with hydrofluoric acid (HF) release. The sensors fabricated using Cavity-SOI exhibit a sensitivity of 100.695 Hz/kPa, a working temperature range spanning from -10-60 °C, a pressure range of 1-120 kPa, and a maximum error of less than 0.012% full scale (FS). The developed micromachining process for Cavity-SOI not only streamlines the fabrication process but also addresses several challenges inherent in traditional MEMS fabrication. The successful fabrication and performance validation of the MEMS RPS confirm the effectiveness and practicality of the proposed method. This breakthrough paves the way for the development of high-performance MEMS devices, opening up new possibilities for various applications in different industries.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"16 3","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11944984/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143720243","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":"Investigation of Transient Thermal Behavior in Thyristors Under Pulse Conditions.","authors":"Guanxiang Zhang, Xiao Zhang, Junyong Lu, Yufeng Dai, Tao Ma, Bofeng Zhu","doi":"10.3390/mi16030291","DOIUrl":"10.3390/mi16030291","url":null,"abstract":"<p><p>Under pulsed discharge conditions, high-power thyristors face challenges such as an excessively high current rise rate (di/dt) and the issue of triggering front expansion, which are difficult to accurately simulate. Traditional modeling approaches often neglect the non-uniform distribution and expansion process of the internal current within the silicon wafer. In this study, we address these limitations by incorporating these critical factors into our analysis. Using a two-dimensional device-circuit co-simulation approach, we investigate the current, temperature, and thermal power distribution within the thyristor during the turn-on process under pulsed discharge conditions. Based on the simulation results, we derive the velocity equation governing the transverse expansion of the thyristor current. Furthermore, we establish a three-dimensional finite element model of the thyristor and develop a generalized extended model for complex gate structures. These models enable us to obtain the transient temperature distribution during the thyristor turn-on process under pulsed conditions. Finally, we conduct cycle surge life tests on various types of thyristors, providing valuable insights for the selection and optimization of thyristors designed for pulsed applications.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"16 3","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11944675/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143720230","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":"Ultra-Wideband Passive Polarization Conversion Metasurface for Radar Cross-Section Reduction Across C-, X-, Ku-, and K-Bands.","authors":"Xiaole Ren, Yunqing Liu, Zhonghang Ji, Qiong Zhang, Wei Cao","doi":"10.3390/mi16030292","DOIUrl":"10.3390/mi16030292","url":null,"abstract":"<p><p>In this study, we present a novel ultra-wideband passive polarization conversion metasurface (PCM) that integrates double V-shaped patterns with circular split-ring resonators. Operating without any external power supply or active components, this design effectively manipulates the polarization state of incident electromagnetic waves. Numerical and experimental results demonstrate that the proposed PCM can convert incident linear polarization into orthogonal states across a wide frequency range of 7.1-22.3 GHz, encompassing the C-, X-, Ku-, and K-bands. A fabricated prototype confirms that the polarization conversion ratio (PCR) exceeds 90% throughout the specified band. Furthermore, we explore an additional application of this passive metasurface for electromagnetic stealth, wherein it achieves over 10 dB of monostatic radar cross-section (RCS) reduction from 7.6 to 21.5 GHz. This broad effectiveness is attributed to strong electromagnetic resonances between the top and bottom layers, as well as the Fabry-Pérot cavity effect, as evidenced by detailed analyses of the underlying physical mechanisms and induced surface currents. These findings confirm the effectiveness of the proposed design and highlight its potential for future technological applications, including 6G communications, radar imaging, anti-interference measures, and electromagnetic stealth.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"16 3","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11946656/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143720513","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":"Ultrasonic Signal Processing Method for Dynamic Burning Rate Measurement Based on Improved Wavelet Thresholding and Extreme Value Feature Fitting.","authors":"Wenlong Wei, Xiaolong Yan, Juan Cui, Ruizhi Wang, Yongqiu Zheng, Chenyang Xue","doi":"10.3390/mi16030290","DOIUrl":"10.3390/mi16030290","url":null,"abstract":"<p><p>Ultrasonic measurement techniques are increasingly used to measure the burning rates of solid rocket fuel, but challenges arise due to noise and signal attenuation caused by the motor's multi-layered structure. This paper proposes an adaptive thresholding method combined with a wavelet threshold function for effective ultrasonic signal denoising. Additionally, an extreme value feature fitting algorithm is introduced for accurate echo signal localization, even in low signal-to-noise ratio (SNR) conditions. Numerical simulations show a 10 dB improvement in SNR at -20 dB, with a correlation coefficient of 0.83 between the denoised and true signals. Echo localization tests across 12 SNR levels demonstrate a consistent error below 1 μs. Compared to other algorithms, the proposed method achieves higher precision, with a maximum displacement error of 0.74 mm. Hardware-in-the-loop experiments show an increase in SNR from -15 dB to 5.78 dB, with maximum displacement and rate errors of 0.9239 mm and 0.781 mm/s. In fuel-burning experiments, the burning rate curve closely matches the theoretical curve, with an initial fuel thickness error of only 0.12 mm, confirming the method's effectiveness in complex environments.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"16 3","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11945480/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143720510","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":"One-Step Fabrication of Microfluidic Channels in Polydimethylsiloxane: Influence of Laser Power on Channel Formation.","authors":"Seong-Yeop Kim, Han-Byeol Son, Hyo-Ryoung Lim","doi":"10.3390/mi16030282","DOIUrl":"10.3390/mi16030282","url":null,"abstract":"<p><p>Recent advancements in microfluidic technologies have revolutionized their applications, particularly in drug monitoring, continuous biochemical analysis, and real-time physiological assessments. However, the fabrication of microfluidic devices with precise flow control remains constrained by either cost-prohibitive photolithography processes or limited-precision 3D printing techniques. In this study, we propose a one-step fabrication method employing picosecond laser processing to directly create microfluidic channels in (PDMS). This method achieves micron-scale channel precision while significantly simplifying the fabrication process and reducing costs. This approach eliminates the need for additional encapsulation steps, further reducing contamination risks and improving production scalability. These findings highlight the potential of this fabrication method to advance next-generation wearable biochemical devices and personalized healthcare technologies.</p>","PeriodicalId":18508,"journal":{"name":"Micromachines","volume":"16 3","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11944243/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143720314","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}