Letteratura scientifica selezionata sul tema "N/MOEMS"

The paper presents several statements of the problems of synthesis of holographic mask in the form of optimization problems for quality of holographic images. An effective algorithm for the synthesis of holographic masks based on FFT with complexity O(NlnN), where N is the number of elements of the depicted object, is described. Based on this algorithm, a scalable software package has been developed and implemented that allows synthesizing holographic masks for various lithography applications, including the production of MEMS, MOEMS and high-end chips. Experimental results are presented.

Wafer bonding is a critical manufacturing process for a vast number of experimental and commercial microelectromechanical system (MEMS) devices [1-5]. Wafer bonding is used for both the hermetic sealing of MEMS [3-5], and for integrating MEMS with electronic integrated circuits (IC) [1-2]. In this invited talk we present recent examples of wafer bonding approaches targeted at hermetic sealing of emerging MEMS devices such as silicon photonic MEMS [3, 4]. In these processes, the MEMS are sealed by wafer bonding and transferring individual lids, while at the same time keeping the final total die thickness as thin as possible. Furthermore, we also present examples of wafer bonding techniques targeted at integrating MEMS or nanoelectromechanical systems (NEMS) directly on top of electronic integrated circuits (IC), thereby closely packaging the MEMS devices with the electronic circuits that provide an interface to the outside world [1-2]. Ultimately the presented wafer bonding approaches can contribute to further miniaturization and thickness reduction of the final packaged MEMS components. REFERENCES [1] Fischer, A.C., Forsberg, F., Lapisa, M., Bleiker, S.J., Stemme, G., Roxhed, N. and Niklaus, F., 2015. Integrating mems and ics. Microsystems & Nanoengineering, 1(1), pp.1-16. [2] Lapisa, M., Stemme, G. and Niklaus, F., 2011. Wafer-level heterogeneous integration for MOEMS, MEMS, and NEMS. IEEE Journal of Selected Topics in Quantum Electronics, 17(3), pp.629-644. [3] Jo, G., Edinger, P., Bleiker, S.J., Wang, X., Takabayashi, A.Y., Sattari, H., Quack, N., Jezzini, M., Lee, J.S., Verheyen, P. and Zand, I., 2022. Wafer-level hermetically sealed silicon photonic MEMS. Photonics Research, 10(2), pp.A14-A21. [4] Edinger, P., Jo, G., Van Nguyen, C.P., Takabayashi, A.Y., Errando-Herranz, C., Antony, C., Talli, G., Verheyen, P., Khan, U., Bleiker, S.J. and Bogaerts, W., 2023. Vacuum-sealed silicon photonic MEMS tunable ring resonator with an independent control over coupling and phase. Optics Express, 31(4), pp.6540-6551. [5] Wang, X., Bleiker, S.J., Edinger, P., Errando-Herranz, C., Roxhed, N., Stemme, G., Gylfason, K.B. and Niklaus, F., 2019. Wafer-level vacuum sealing by transfer bonding of silicon caps for small footprint and ultra-thin MEMS packages. Journal of microelectromechanical systems, 28(3), pp.460-471. Figure 1

Two new annual fishes are described from the upper Rio Purus drainage, Amazonian basin, northern Brazil. Moema apurinan, new species, is similar to M. staecki, these two species distinguished from other congeners in having contact organs on scales of the flank in males, an acuminate caudal fin, fewer pectoral-fin rays, fewer vertebrae, and a narrower rostral cartilage. Moema apurinan differs from M. staecki in having a longer pectoral fin and a wider basihyal. Moema apurinan is distinguished from all other congeners by possessing fewer caudal-fin rays. Aphyolebias boticarioi, new species, differs from all other congeners by having a deeper body. It is similar to A. rubrocaudatus, A. obliquus, A. claudiae and A. schleseri in having a ventral marginal black stripe on the caudal fin in males. Aphyolebias boticarioi differs from these species by a combination of features including number of anal-fin rays, pectoral-fin rays, vertebrae and gill-rakers, and color patterns.

BackgroundMalignancies under the treatment of biologic agents (Bio) or JAK inhibitors (JAKi) are attracting public attention[1] [2]. It is important to administer Bio or JAKi safely to the patients, it seems to be absolutely necessary of the screening of cancer. Intensive pre-screening examinations for malignancies before the treatment of Bio or JAKi has been performed in our department since 2016.ObjectivesTo elucidate the utility of the intensive pre-screening examination and the prevalence of malignancies prior to the therapy of Bio or JAKi to the patients of connective tissue diseases (CTD).MethodsThree hundred thirty-six CTD patients (RA:254, SLE:27, SpA:25, Vasculitis:13, Overlap syndrome:6, others:11) before the administration of Bio or JAKi were enrolled from April 2016 to September 2021. Upper gastric intestinal endoscope, fecal occult blood test (twice), thyroid and abdominal ultrasound, chest and abdominal non-contrast enhanced CT, serum prostate-specific antigen (only for male) and screening for the cancer of the cervix and mammography (only for female) were performed to all patients above as an intensive pre-screening examination. Herein, we retrospectively analyzed the prevalence of both benign and malignant tumors including species before the therapy of Bio or JAKi, and the patient-treatment outcomes with cancers.ResultsThe patient characteristics were as follows: Median age: 68 yr.(n=336). (RA:69 yr., SLE:48yr., SpA:63yr., Vasculitis:73yr., Overlap syndrome:70yr., others:57yr.). The prevalence of benign tumors and malignant tumors were 24.7% (n=83, median age:68yr.) and 5.1% (n=17, median age:74yr.<Max:89yr. Min:50yr.>), respectively. The details of the malignancies were prostate cancer (n=6, 35.3%), uterus or ovarian cancer (n=3, 17.6%), gastric cancer (n=3, 17.6%), colon cancer (n=2, 11.8%), breast cancer (n=1,5.9%), lung cancer (n=1, 5.9%) and thyroid cancer (n=1, 5.9%). Most of the age complicated with cancers was 80yr (median) except for those of uterus or ovarian cancer:50yr(median). Eleven patients (64.7%) among cancer bearing patients (n=17) successfully administered Bio or JAKi after radical operation such as endoscopic or surgical resection and all of the 11 patients achieved clinical remission.ConclusionSubclinical malignancies were detected by means of intensive pre-screening examinations. The most common cancer was prostate cancer, subsequently uterus or ovarian cancer and gastric cancer. It is important to perform pre-screening examinations before an aggressive therapy such as Bio or JAKi to CTD patients.References[1]N Engl J Med 2022;27;386(4):316-326[2]Rheumatol Ther 2017;4:333-347Acknowledgements:NIL.Disclosure of InterestsKenta Misaki Speakers bureau: Astellas, Bayer, Boehringer Ingelheim, Eli Lilly, Chugai, Sanofi, Kyowa-Kirin, Abbvie, Kowa, Pfizer, Ono Pharmaceutical, UCB, Mitsubishi-Tanabe, Gilead Sciences, Nippon Shinyaku, Novartis, Eisai, Janssen, Taisho, Teijin, VIATRIS and Asahi-kasei; and has received research grants from Ono Pharmaceutical, Grant/research support from: ONO PHARMACEUTICAL CO., LTD, Yamamoto Mako: None declared, Takuya Okada: None declared, Yusuke Tarutani: None declared, Moemi Yabe: None declared, Kenshi Inoue: None declared, Naofumi Dobashi: None declared, Yasuhiko Imaizumi: None declared.

Lithium metal has been considered as a promising candidate for the negative electrode of secondary batteries for several decades because its capacity (3860 mAh g–1) is higher than those of currently used electrode materials. However, the lithium metal anode has been known to exhibit poor cycle performance or give rise to short circuits due to the dendritic or whisker-like morphology of lithium formed during deposition and dissolution. Analysis of the morphology of lithium deposits, especially the cross-section, is considered to be important for contributing to research on improving the charge-discharge ability of lithium metal anode. The formation of a uniform and highly Li+conductive solid electrolyte interphase (SEI) on the lithium metal surface leading to dense and low porosity lithium deposits and a reversible deposition-dissolution reaction of lithium is a significant challenge. It has been suggested that the bis(fluorosulfonyl)amide (FSA–)-derived SEI in ionic liquid (IL) electrolyte containing a high concentration of LiFSA can improve cycle performance and suppress dendritic growth [1,2]. We have reported the cycle performance of lithium and the formation of a SEI for electrolytes comprised of LiFSA in MOEMPFSA (MOEMP+: 1-methyl-1-methoxyethylpyrrolidinium) or BMPFSA (BMP+: 1-methyl-1-butylpyrrolidinium) [3]. The resistance of the SEI in LiFSA-MOEMPFSA (1:1 molar ratio) was lower than that in LiFSA-BMPFSA (1:1 molar ratio), and the deposition and dissolution performance of a lithium metal anode was improved in LiFSA-MOEMPFSA compared to LiFSA-BMPFSA. This is thought to be due to the variation in SEI composition with IL cation structure. Previous studies have demonstrated the cycle performance at a capacity of 1 or 4 mAh cm–2 [3,4] for lithium metal. However, these values are rather low when considering the proposed application as a negative electrode material for next-generation batteries, and it is essential to study a larger capacity. In the present study, the morphological changes of Li during deposition and dissolution cycle at 10 mAh cm–2 and the relationship between cycle performance and the morphology of deposited Li was investigated. The electrolytes were prepared by mixing MOEMPFSA or BMPFSA and LiFSA at 50.0-50.0 mol%. The water contents in the ionic liquid electrolytes were less than 50 ppm, as determined by Karl Fischer titration. The preparation of 10 mAh cm–2 deposited Li on Cu was conducted using a Cu|Li planar electrode cell (laminate-like) at 0.1, 0.5 and 1.0 mA cm–2. Celgard 3501 was used as the separator. The cross-sections of the deposited lithium on Cu were revealed by processing with Ar ion milling at –80 °C. The observation of the cross-section of deposited lithium on Cu was carried out with a scanning electron microscope (SEM) with energy dispersive X-ray spectroscopy (EDX) and without exposure to air. The SEM images of the cross-sections of a 10 mAh cm–2 lithium deposit on Cu at 0.1 or 0.5 mA cm–2 in LiFSA-MOEMPFSA reveal a denser and lower porosity than that at 1.0 mA cm–2. It is suggested that columnar growth of lithium was observed due to particle growth rather than nucleation at lower current density. The morphology of the 10 mAh cm–2 lithium deposits on Cu at 0.5 mA cm–2 in LiFSA-MOEMPFSA was denser than that in LiFSA-BMPFSA. This is thought to be due to the differences in the resistance of the SEI derived from MOEMPFSA and BMPFSA. The denser and lower porosity deposited lithium is considered to be promising for operation at as high a capacity as 10 mAh cm–2, and is expected to contribute to the improvement of the reversibility of the lithium anode with suppressing dendritic growth. Acknowledgments This study was supported by the Green Technologies of Excellence (GteX, JPMJGX23S0) program of the Japan Science and Technology Agency (JST). MOEMPCl was supplied by Nisshinbo Holdings Inc. References R. Furuya, T. Hara, T. Fukunaga, K. Kawakami, N. Serizawa, and Y. Katayama, J. Electrochem. Soc., 168, 100516 (2021). G. Girard, M. Hilder, N. Dupre, D. Guyomard, D. Nucciarone, K. Whitbread, S. Zavorine, M. Moser, M. Forsyth, D. MacFarlane, and P. Howlett, ACS Appl. Mater. Interfaces, 10, 6719 (2018). N. Serizawa, R. Yamashita, and Y. Katayama, J. Phys. Chem. C, 127, 10434 (2023). Y. Maeyoshi, K. Yoshii, and H. Sakaebe, J. Electrochem. Soc., 90, 047001 (2022).

This paper reports the development and integration of (Poly‐Si/Air)n Distributed BRAGG Reflectors (DBR) in a MOEMS Fabry‐Pérot‐Interferometer (FPI) concept. The realized reflectors constitute a promising and resource‐efficient alternative to complex Ion‐Assisted Deposition based DBRs while maintaining their advantages. Compared to state of the art MOEMS FPIs the (Poly‐Si/Air)n DBRs can be integrated into two moveable reflector carriers based on two individually fabricated wafers which are bonded. The (Poly‐Si/Air)n DBRs are investigated as (HL) and (HL)2 reflector stacks showing a reflectance above 91% within the wavelength range of 2.8–5.7 μm. © 2023 The Authors. IEEJ Transactions on Electrical and Electronic Engineering published by Institute of Electrical Engineer of Japan and Wiley Periodicals LLC.

The fatigue characteristics of microelectromechanical systems (MEMS) material, such as silicon or polysilicon, have become very important. Many studies have focused on this topic, but none have defined a good methodology for extracting the applied stress and predicting fatigue life accurately. In this study, a methodology was developed for the life prediction of a polysilicon microstructure under bending tests. Based on the fatigue experiments conducted by Hocheng et al. (2008, “Various Fatigue Testing of Polycrystalline Silicon Microcantilever Beam in Bending,” Jpn. J. Appl. Phys., 47, pp. 5256–5261) and (Hung and Hocheng, 2012, “Frequency Effects and Life Prediction of Polysilicon Microcantilever Beams in Bending Fatigue,” J. Micro/Nanolithogr., MEMS MOEMS, 11, p. 021206), cantilever beams with different dimensions were remodeled with mesh control technology using finite element analysis (FEA) software to extract the stress magnitude. The mesh size, anchor boundary, loading boundary, critical stress definition, and solution type were well modified to obtain more correct stress values. Based on the new stress data extracted from the modified models, the optimized stress-number of life curve (S–N curve) was obtained, and the new life-prediction equation was found to be referable for polysilicon thin film life prediction under bending loads. After comparing the literature and confirming the new models, the frequency effect was observed only for the force control type and not for the displacement control type.

Abstract Familial Hypercholesterolemia (FH) is an autosomal dominant genetic disease, characterized by high levels of the cholesterol fraction present in low density lipoprotein (LDLc). FH is associated to early atherosclerotic coronary disease, which can result in acute myocardial infarction and angina pectoris. Clinical diagnosis of FH in adults is based on elevated LDLc levels ≥ 4,9 mmol/L and total cholesterol (TC) ≥ 7,5 mmol/L; in untreated children and adolescents LDLc ≥ 4,0 mmol/L and TC ≥ 6,7 mmol/L, associated or not with physical signs (xanthomas, corneal arch). In Brazil, it is estimated that there are from 402,000 to 607,000 cases of FH. This study aimed to evaluate the genetic variants related to FH in a small region from Minas Gerais, a southeast state in Brazil. Fifteen index cases (IC) were selected in two cities (Bom Despacho and Moema), that comprise 1.416 km2 in that region. Family members (n=69) were also selected, when possible, for genetic analysis, which was carried out by the NGS (Next Generation Sequencing) method, using Illumina® technology. Six different genetic variants were identified: 1) Pathogenic variants in LDLR gene - Asp224Asn in 74 individuals (10 IC); Cys34Arg in 1 individual (1 IC); Asp601His in 2 individuals (1 IC); and Ser854Gly in 2 individuals (1 IC); 2) Variant of uncertain significance (VUS) in APOB gene - Met499Val in 1 individual (1 IC); and 3) VUS in PCSK9 gene - Arg237TRP in 4 individuals (1 IC). All variants were identified in heterozygosis. The data suggest that the high prevalence of FH in that small region in Brazil is related to inbreeding observed in the families investigated. In addition, a founder effect could also contribute to the elevated frequency of LDLR gene variants, mainly Asp224Asn. The data show the importance of molecular investigation on clinical conduct in FH Brazilian patients and their family members.

Les systèmes micro et nanoélectromécaniques sont largement explorés pour des applications en photonique intégrée et pour sonder des phénomènes physiques fondamentaux. Un important corpus de recherches se concentre sur les dynamiques linéaires et non linéaires des résonateurs couplés ainsi que leurs comportements collectifs. Cette thèse présente la conception, la fabrication et la caractérisation de membranes opto-électromécaniques nanométriques couplées, dans les régimes linéaires et non linéaires, et est divisée en trois parties principales. La première partie détaille la conception, l'optimisation et la fabrication de résonateurs à membrane couplée qui sont mis en mouvement grâce à des électrodes interdigitées placées à quelques centaines de nanomètres sous la membrane. Les déplacements mécaniques de ces membranes sont lus par des moyens optiques. Afin d'améliorer la réflectivité et donc la lecture optique, des miroirs à cristaux photoniques sont conçus au sein de chaque membrane. Sur la base de simulations numériques, les modes propres mécaniques, l'efficacité de l'excitation électromécanique et le couplage mécanique entre les membranes sont discutés et évalués. La deuxième partie se concentre sur la dynamique linéaire et non linéaire de deux résonateurs couplés. Nous présentons un modèle pour caractériser la réponse du système dans le régime linéaire, en montrant comment les forces externes ont un impact sur les dynamiques en amplitude et en phase. Les expériences démontrent un contrôle interférométrique sur les réponses mécaniques par le biais d'une double excitation, conduisant à des phénomènes de type CPA (Coherent Perfect Absorption). Dans ce cadre, l'amplification et l'annihilation de la réponse en amplitude sont démontrées. De plus, grâce à la mesure de la phase, nous démontrons la présence d'une charge topologique dans l'espace des paramètres étudiés ainsi qu'une nouvelle stratégie pour l'amplification de phase d'un petit signal. Des forces électriques plus fortes induisent des non-linéarités mises en évidence par des bistabilités et modélisées par des résonateurs de Duffing couplés. L'implémentation d'une boucle de rétroaction électrique envoyant le signal enregistré d'une membrane à l'autre permet de contrôler les bistabilités. En outre, elle permet également d'accéder à des régions de multistabilité ouvrant ainsi de nouvelles voies vers des processus physiques et dynamiques plus riches et complexes. La troisième partie étend ces recherches au cas plus complexe de trois membranes couplées. Ici, nous explorons d'abord le système dans son régime linéaire et développons des techniques pour contrôler expérimentalement les modes propres mécaniques. Pour ce faire, les actionnements électriques ainsi que les moyens de lecture optique peuvent être réglées pour ajuster les résonances mécaniques. Ainsi, dans le régime linéaire, les résonances de Fano dues aux interférences entre modes de résonance sont révélées et contrôlées par des moyens in situ. En augmentant la force d'actionnement, on atteint un régime non linéaire où des régions de verrouillage de phase sont identifiées. Cela démontre l'interaction entre les résonances de Fano et la synchronisation dans un large espace de paramètres. Enfin, nous ouvrons des perspectives de recherche sur le comportement collectif et les phénomènes plus complexes dans des réseaux de résonateurs non linéaires couplés de plus grande taille. Cela nécessite d'explorer différents schémas de couplage et de relever les défis des techniques de détection. À terme, cela pourrait contribuer à des applications prometteuses dans le domaine de la modulation optique à faible puissance, des technologies de détection et des systèmes électro-optomécaniques non linéaires avancés
Micro and nanoelectromechanical systems are widely explored for applications in integrated photonics and for probing fundamental physical phenomena. A significant body of research focuses on coupled resonators' linear and nonlinear dynamics and their collective behaviors. This thesis presents the design, fabrication, and characterization of coupled nano-opto-electromechanical membranes in both linear and nonlinear regimes and is divided into three main parts. The first part details the design, optimization, and fabrication of coupled membrane resonators, which are put into motion thanks to interdigitated electrodes placed at a few hundred nanometers underneath the membrane. The mechanical displacement of these membranes is read by optical means. In order to enhance the reflectivity and thus the optical reading, photonic crystal mirrors are designed on each membrane. Based on numerical simulation, mechanical eigenmodes, electromechanical excitation efficiency, and mechanical coupling between membranes are discussed and assessed. The second part focuses on the linear and nonlinear dynamics of two coupled resonators. We present a model for characterizing the system's response in the linear regime, showing how external forces impact the amplitude and phase dynamical responses. Experiments demonstrate interferometric control over mechanical responses through double excitation, leading to CPA-like (Coherent Perfect Absorption) phenomena. Within this framework, amplification and annihilation of amplitude response is demonstrated. Moreover, thanks to the phase dynamics, we demonstrate a topological charge in the parameter space studied as well as a new strategy for phase amplification of small signals. Stronger electrical forces induce nonlinearities highlighted by bistabilities and modeled by coupled Duffing resonators. The implementation of an electrical feedback loop by sending the recorded signal from one membrane to the other allows the control of bistabilities. Beyond this, it also allows access to multistability regions, opening new avenues towards richer physics and more complex dynamical processes. The third part expands these investigations to the more complex case of three coupled membranes. Here, we first explore the system in its linear regime and develop techniques to experimentally control mechanical eigenmodes. In order to do so, electrical actuators, as well as optical readings, can be adjusted to tune mechanical resonances. Thus, in the linear regime, Fano resonances due to interferences between resonant modes are revealed and controlled by in-situ means. By pushing towards stronger actuation, a nonlinear regime is reached where phase-locking regions are identified. This demonstrates the interplay between Fano resonances and synchronization in a large parameter space. Finally, we provide perspectives for further research on collective behavior and more complex phenomena in larger nonlinear coupled resonator arrays. This requires exploring different coupling schemes and challenges related to detection techniques. Down the line, this may contribute to promising applications in low-power optical modulation, sensing technologies, and advanced nonlinear electro-optomechanical systems