Journal of Micromechanics and Microengineering最新文献

{"title":"Precise In-situ Fabrication of Perovskite Single Crystal Arrays via Cosolvent based Electrohydrodynamic Printing","authors":"Rui Yu, Wenshuo Xie, Weili Yang, Xinrui Yang, Yongqing Duan","doi":"10.1088/1361-6439/ad1b1b","DOIUrl":"https://doi.org/10.1088/1361-6439/ad1b1b","url":null,"abstract":"\u0000 Single crystal (SC) perovskites exhibit superior stability and optoelectronic performance compared to polycrystalline ones, offering significant potential for high-performance and low-cost photovoltaic/optoelectronic applications. However, conventional SC growth processes often require intricate cutting or transferring of SC in the manufacturing of optoelectronic devices. High-resolution, in-situ, and scalable fabrication of perovskite SC arrays remain challenging. In this work, we propose a method for in-situ deposition of cosolvent based perovskite precursor solutions using electrohydrodynamic (EHD) printing technology. The addition of a cosolvent (which exhibits good chemical compatibility with the precursor and the main solvent, accompanied by lower solubility and vapor pressure) to the mixed solution promotes early-stage supersaturation and nucleation in the solution, enabling precise control over crystal morphology, size, and positioning through in-situ EHD printing. The effect of different cosolvent ratios on SC growth and the inhibition of parasitic crystallization by altering the contact angle of substrate were investigated. Finally, the parameters for precise control of the EHD printing process were investigated, enabling the growth of SC arrays ranging from 1 to 35 μm in size. This strategy offers a direct patterning approach for SC perovskite preparation without complex temperature control or multi-step operation. The printed patterns exhibit high resolution and excellent uniformity, offering significant potential for manufacturing SC-based perovskite optoelectronic devices with precise size and positioning control.","PeriodicalId":16346,"journal":{"name":"Journal of Micromechanics and Microengineering","volume":"7 10","pages":""},"PeriodicalIF":2.3,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139385325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electrostatically actuated all metal MEMS Pirani gauge with tunable dynamic range","authors":"Manu Garg, D. S. Arya, Sushil Kumar, Khanjan Joshi, M. Yousuf, Yi-Yen Chiu, PUSHPAPRAJ SINGH","doi":"10.1088/1361-6439/ad1b1a","DOIUrl":"https://doi.org/10.1088/1361-6439/ad1b1a","url":null,"abstract":"\u0000 An electrostatically actuated all-metal MEMS Pirani gauge with a tunable dynamic range is proposed. Contrary to the conventional fixed gap Pirani gauges, an electrostatic mechanism is employed to tune the gaseous conduction gap. Due to the electrostatic force between the heating element and heat sink, this tuning results in shifting the transition pressure to a higher pressure. As a result, the operating range of the Pirani gauge can be tuned depending on the magnitude of the actuation voltage. Theoretical estimation of the transition pressure corresponding to different gaseous conduction gaps is also presented. Depending on the available margin of gap tuning, the electromechanical and electrothermal analyses are carried out in COMSOL Multiphysics. The analytical approach is validated by experimentally characterizing the fabricated device. The experimentally tested device with the proposed actuation mechanism shows an 11.2 dB increase in dynamic range in comparison to the conventional design. In a CMOS-compatible fabrication process flow, the proposed gauge can be used to monitor vacuum from 40 Pa to 5×10^5 Pa with the electrostatic actuation.","PeriodicalId":16346,"journal":{"name":"Journal of Micromechanics and Microengineering","volume":"50 8","pages":""},"PeriodicalIF":2.3,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139385803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Carbon dioxide reduction utilizing a bismuth halide perovskite as immobilized photocatalyst in a 3D printed microreactor","authors":"José Andrés Santamaría Cordero, Hannia López Mena, Marisol Ledezma, Leslie W. Pineda, J. E. Duran Herrera","doi":"10.1088/1361-6439/ad1b1c","DOIUrl":"https://doi.org/10.1088/1361-6439/ad1b1c","url":null,"abstract":"\u0000 The rising concerns about CO2 levels in the atmosphere and energy dependency on non-renewable sources, such as fossil fuels, could find an integral solution in CO2 photocatalytic reduction. The present work explores two alternatives to the main hindering factors for this reaction, i.e., the reactor configuration and the photocatalyst utilized. A microreactor was designed and 3D printed, providing a cheap and versatile reaction platform. Three bismuth halide perovskites, Cs3Bi2Cl9, Cs3Bi2I9, and Cs4MnBi2Cl12, were synthesized and characterized by their band gaps (Eg); Cs3Bi2I9 presented the lowest Eg and was therefore chosen for further evaluation as potential CO2-reduction photocatalyst. Aqueous-phase photocatalytic CO2 reduction was achieved using this perovskite in the microreactor, obtaining CO as a reduction product with maximal production rates of 737 μmol gcat\u0000 -1 h-1. The reaction system was evaluated under different flow rates and light intensities. A balance between space-time and reactant feed was found to define the behavior of CO concentration and production in the microreactor. For the light intensity, it was observed that as it increased, both CO production and concentration increased due to generating more electron-hole pairs, favoring the photocatalytic reaction. With these results, Cs3Bi2I9 perovskite immobilized in the designed microreactor demonstrates having great potential as an effective CO2 photocatalytic reduction system.","PeriodicalId":16346,"journal":{"name":"Journal of Micromechanics and Microengineering","volume":"38 4","pages":""},"PeriodicalIF":2.3,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139385951","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Large Area Nanoscale Patterning of Functional Materials Using Organosilicate ink based Nanotransfer Printing","authors":"Stephen Binderup, V. Korampally","doi":"10.1088/1361-6439/ad1b1d","DOIUrl":"https://doi.org/10.1088/1361-6439/ad1b1d","url":null,"abstract":"\u0000 This paper presents a versatile nanotransfer printing method for achieving large-area sub-micron patterns of functional materials. Organosilicate ink formulations combined with effective release layers have been shown to facilitate patterning of materials through the commonly used patterning approaches – lift off, physical etching and chemical etching. In this paper, we demonstrate that organosilicate ink formulations function as an effective resist owing to its superior physico-chemical stability whereas the release layers ensure clean removal of the resist post patterning. We successfully demonstrate patterning of sub-micron structures (800 nm feature sizes) of chromium metal through the lift off approach, silicon through reactive ion etching technique and silicon dioxide through wet chemical etching technique illustrating the versatility of the reported method. This patterning methodology represents a significant advancement in enabling nanostructure fabrication within resource-constrained laboratories. The approach requires nothing more than a master mold containing the desired structures, a spin coater, a low-temperature hotplate, and a desktop reactive ion etch tool.","PeriodicalId":16346,"journal":{"name":"Journal of Micromechanics and Microengineering","volume":"33 4","pages":""},"PeriodicalIF":2.3,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139385215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seven-shaped beam design for improving the sensitivity of two-dimensional MEMS sensors","authors":"Nanyan Zhou, Wu Liu, Feng Cui, Xinwei Zhang, Leyang Lv","doi":"10.1088/1361-6439/ad1709","DOIUrl":"https://doi.org/10.1088/1361-6439/ad1709","url":null,"abstract":"\u0000 The stiffness of the connecting beam is one of the most crucial factors affecting the performance of MEMS sensors. Many traditional methods reduce the stiffness by changing the parameters or number of connecting beams. This paper introduces a seven-shaped beam structure used for MEMS sensor. The acute angle between its two segments of seven-shaped structure realizes lower stiffness. Compared with the crab-leg beam, it can bring a maximum sensitivity gain of 1.29 times through different included angle designs. At the same time, compared with the combined beam, seven-shaped combined beam can bring a maximum sensitivity gain of 1.6 times. By using the seven-shaped beam, the two-dimensional MEMS sensor has been designed and fabricated. According to the experimental results, it achieved a detection sensitivity of 25 fF/g. The relative error of the differential capacitance change between the measurement result and the simulation result is only 8.6%.","PeriodicalId":16346,"journal":{"name":"Journal of Micromechanics and Microengineering","volume":" 5","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138960716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design and fabrication of microfluidic devices: a cost-effective approach for high throughput production","authors":"Tony Thomas, Amit Agrawal","doi":"10.1088/1361-6439/ad104b","DOIUrl":"https://doi.org/10.1088/1361-6439/ad104b","url":null,"abstract":"Microdevices have been recognized as a potential platform for performing numerous biomedical analysis and diagnostic applications. However, promising and viable techniques for a cost-effective and high throughput production of microfluidic devices still remain as a challenge. This paper addresses this problem with an alternative solution for the fabrication of microfluidic devices in a simple and efficient manner. We utilized laser-assisted engraving technique to fabricate a master mold on an acrylic sheet of different thicknesses from 4 to 20mm. Low cost indigenously developed CO₂ (10.6<italic toggle=\"yes\">μ</italic>m wavelength) laser engraving device was used for the experiments. The effect of various laser parameters such as power and speed of operation on the height of engraved structures was studied in detail. Optimal engraving results were obtained with a laser speed of 200–250mm s⁻¹ with a spacing interval of 0.002mm at a laser power of 10–12W. Master mold of microdevice with a channel width of 100<italic toggle=\"yes\">μ</italic>m were produced using this technique. The replica transfer was performed by a simple imprinting method using a benchtop universal testing machine that can provide a maximum compressive load upto 1kN. The replicas were successfully generated on various thin film substrates including polymers, plastics, Whatman filter paper, teflon, vinyl sheets, copper, and aluminum sheets. The effect of load applied on the depth of the microfluidic channel was studied for the substrates such as teflon and Whatman filter paper. A load of 1kN can generate a depth of a few hundred micrometers on various substrates mentioned above. The replicas were also transferred to thermoformable PETG (polyethylene terephthalate glycol) sheets under load with an elevated temperature. The channel-imprinted PETG substrates were later sandwiched between two acrylic sheets with adhesive-coated polymer sheets and screws at the corners. Soft lithographic techniques were also performed to replicate the channel on a poly dimethyl siloxane substrate which was later bonded to a glass plate using an oxygen plasma cleaner device. Fluidic flow testing was conducted by pumping dye-mixed deionized (DI) water through the channels using a syringe pump and connecting tubes at a constant flow rate of 5ml min⁻¹. The outcomes of this study provide an alternative solution for a simple and low-cost method for microdevice fabrication at a large scale.","PeriodicalId":16346,"journal":{"name":"Journal of Micromechanics and Microengineering","volume":"34 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138686502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"One-to-two internal resonance in a micro-mechanical resonator with strong Duffing nonlinearity","authors":"Jun Yu, Ata Donmez, Hansaja Herath, Hanna Cho","doi":"10.1088/1361-6439/ad0de8","DOIUrl":"https://doi.org/10.1088/1361-6439/ad0de8","url":null,"abstract":"This paper investigates the implementation of 1:2 internal resonance (InRes) in a clamped–clamped stepped beam resonator with a strong Duffing effect, focusing on its potential for frequency stabilization in micro-electro-mechanical systems (MEMS) resonators. InRes can arise in a nonlinear system of which mode frequencies are close to an integer ratio, facilitating the internal exchange of energy from an externally driven mode to an undriven mode. The presence of 1:2 InRes and Duffing hardening nonlinearity can result in frequency saturation phenomena, leading to a flat amplitude-frequency response range, which forms the basis for frequency stabilization. The stepped beam resonator design, combined with thermal frequency tuning, enables precise alteration of the frequency ratio between the second and third flexural modes required to achieve the desired 1:2 ratio for InRes. Experimental characterization and theoretical analysis revealed that frequency mismatch plays a significant role, with larger mismatch conditions leading to stronger energy exchange and a wider range of drive force for frequency saturation. The study highlights the frequency saturation mechanism utilizing 1:2 InRes and emphasizes the advantage of Duffing nonlinearity and larger intermodal frequency mismatch for broader frequency stabilization, providing valuable insights for the design and optimization of MEMS resonators.","PeriodicalId":16346,"journal":{"name":"Journal of Micromechanics and Microengineering","volume":"1 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138686541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Relationship between bonding strength and surface roughness in low-temperature bonding of glass for micro/nanofluidic device","authors":"Ryoichi Ohta, Kyojiro Morikawa, Yoshiyuki Tsuyama, Takehiko Kitamori","doi":"10.1088/1361-6439/ad104c","DOIUrl":"https://doi.org/10.1088/1361-6439/ad104c","url":null,"abstract":"The bonding of glass substrates is an important process in the fabrication of glass micro/nanofluidic devices. In this study, the influence of the surface roughness of glass substrates after low-temperature bonding is investigated. It is found that plasma etching can be used to control the surface roughness to the range 2–9 nm. Substrates with a roughness of 5 nm or less can be bonded. The pressure capacity of devices tends to decrease with increasing surface roughness. A pressure capacity of 500 kPa or higher is obtained with a surface roughness of 2 nm or less. This criterion for bonding conditions can be applied to roughness formed by other methods (e.g. via a Cr layer). The proposed approach will facilitate the design and fabrication of glass micro/nanofluidic devices, especially those that complicated fabrication processes or embedding of multiple materials.","PeriodicalId":16346,"journal":{"name":"Journal of Micromechanics and Microengineering","volume":"16 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138686787","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A combined MEMS thermal vacuum sensor with a wide pressure range","authors":"Chuang Yuan, Jianyu Fu, Fan Qu, Qiong Zhou","doi":"10.1088/1361-6439/ad104d","DOIUrl":"https://doi.org/10.1088/1361-6439/ad104d","url":null,"abstract":"MEMS thermal vacuum sensors have been widely applied in many academic and industry fields, and pressure range is a key performance of MEMS thermal vacuum sensors. To extend the pressure range, a combined MEMS thermal vacuum sensor that consists of two diode-type MEMS thermal vacuum sensors in series is proposed in this work. The two diode-type sensors are designed to have different areas of sensitive region and distances between sensitive region and heat sink, and their responses to the pressure are from 3.0 × 10⁻³ to 3 × 10⁴ Pa and from 1.7 × 10⁻² to 4.4 × 10⁵ Pa, respectively. By series-connecting them, the combined sensor achieves a pressure range of 1.3 × 10⁻³ to 6.9 × 10⁵ Pa without any additional control circuit. In addition, it possesses a relatively small size of 400 × 300 <italic toggle=\"yes\">μ</italic>m². These indicate that the combined MEMS thermal vacuum sensor has the characteristics of wide pressure range, high sensitivity and small size.","PeriodicalId":16346,"journal":{"name":"Journal of Micromechanics and Microengineering","volume":"1 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138686331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic micromechanical measurement of the flexural modulus of micrometre-sized diameter single natural fibres using a vibrating microcantilever technique","authors":"Ali Reda, Thomas Dargent, Steve Arscott","doi":"10.1088/1361-6439/ad124e","DOIUrl":"https://doi.org/10.1088/1361-6439/ad124e","url":null,"abstract":"\u0000 The dynamic response of a structure is a manifestation of its inherent characteristics, including material density, mechanical modulus, thermo- and viscoelastic properties, and geometric properties. Together, these factors influence how the material behaves in dynamic scenarios, dictating its damping properties and behaviour under varying forces. In this study we present a novel approach to accurately determine the flexural (bending) modulus of microscopic diameter natural fibres (flax) using microcantilever vibration analysis. Traditionally, the characterisation of the mechanical properties of fibres has relied on macroscopic methods such as tensile testing, which often results in high scatter in measurement data; furthermore, tensile testing does not accurately represent microscale or dynamic conditions and can be complex in terms of sample preparation and loading. To address this, we have developed a microscale technique involving the fabrication of microcantilevers using flat polypropylene support chips, inspired by microelectromechanical systems (MEMS) approaches. Our approach provides a refined method for accurately characterising the mechanical modulus of flax fibres, with reduced data dispersion compared to traditional macroscopic testing. Furthermore, by reducing the influence of inherent fibre defects and maintaining homogeneity along the length of the fibre, our micro-scale technique provides reliable modulus determination. This work opens up avenues for improved understanding and application of natural and man-made fibres, such as glass and optical fibres, in a variety of fields.","PeriodicalId":16346,"journal":{"name":"Journal of Micromechanics and Microengineering","volume":"53 6","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138598539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}