{"title":"Bidirectional Thermo-Acoustic Modulator Based on LiNbO₃ Thin Film","authors":"Xuankai Xu;Yushuai Liu;Tao Wu","doi":"10.1109/JMEMS.2024.3510540","DOIUrl":"https://doi.org/10.1109/JMEMS.2024.3510540","url":null,"abstract":"This letter presents a bidirectional thermo-acoustic (TA) modulator utilizing Y36-cut LiNbO<inline-formula> <tex-math>$_{mathbf {3}}$ </tex-math></inline-formula> thin film. The device integrates two TA phase modulators and a one-dimensional (1D) phase-control transducer within a compact footprint of less than 0.35 mm2. The suspended LN thin film TA phase modulator demonstrates a phase response of 17°/mW. The composed TA amplitude modulator supports bidirectional amplitude modulation, achieving over 30 dB modulation at 460 MHz with a control voltage of 1.1 V. This compact and efficient design makes it ideal for phononic integrated circuit (PnIC) and advanced acoustic signal processing applications. [2024-0162]","PeriodicalId":16621,"journal":{"name":"Journal of Microelectromechanical Systems","volume":"34 2","pages":"110-112"},"PeriodicalIF":2.5,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143801072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Disha Chugh;Hyun-Keun Kwon;Gabrielle D. Haddon-Vukasin;Thomas W. Kenny;Saurabh A. Chandorkar
{"title":"Sensing Voltage at Electrically Floating Nodes: A Path Toward Enhancing Performance and Robustness in Capacitive MEMS Resonators","authors":"Disha Chugh;Hyun-Keun Kwon;Gabrielle D. Haddon-Vukasin;Thomas W. Kenny;Saurabh A. Chandorkar","doi":"10.1109/JMEMS.2025.3528762","DOIUrl":"https://doi.org/10.1109/JMEMS.2025.3528762","url":null,"abstract":"Capacitively transduced micromechanical resonators for timing reference applications are overwhelmingly measured from the current output at their sensing electrodes, using a transimpedance amplifier (TIA). Continuous time floating-voltage measurement in capacitive resonators has not found its reach due to various reasons, the primary drawback being picking up of stray charges through stray/unknown capacitances linked to the electrically floating electrode. In this paper, we introduce a novel concept of bias tuning electrodes which alleviates this issue. Through theoretical modelling and experimental evidence, we show that voltage measurement performed at electrically-floating sensing-electrode using a voltage-amplifier (VA) is superior to TIA topology in terms of robustness, noise performance, and bandwidth. Furthermore, we introduce a new electrical circuit equivalent model for resonator devices with a bias tuning electrode in lieu of the standard Mason and Butterworth-Van Dyke (BVD) models which are unsuitable for our new topology. This new model also offers better insights for the combined system of resonator and sensing-unit. The theoretical and experimental work was carried out using a Epi-seal encapsulated DETF device wherein the superior performance of VA topology in key parameters and equivalent performance in other measures is demonstrated. This work is readily extendable to any general capacitively transduced device.[2024-0156]","PeriodicalId":16621,"journal":{"name":"Journal of Microelectromechanical Systems","volume":"34 2","pages":"116-133"},"PeriodicalIF":2.5,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143800756","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Overcoming Welding and Contact Degradation Failures Incurred by Complementary N/MEMS Logic Gate Structures Fabricated on SOI Wafers","authors":"Bennett Smith;Md Ataul Mamun;Benjamin Horstmann;Ümit Özgür;Vitaliy Avrutin","doi":"10.1109/JMEMS.2025.3526543","DOIUrl":"https://doi.org/10.1109/JMEMS.2025.3526543","url":null,"abstract":"Nano/microelectromechanical systems (N/MEMS) based complementary logic circuits offer a physically robust alternative to conventional CMOS control systems, which are able to function in environments unsuitable for transistor devices. In this work we demonstrate novel, configurable, complementary logic circuits comprised entirely of relays at both NEMS and MEMS scale, which are capable of fulfilling all primary logic functions. Lifetime testing of the fabricated devices revealed two key failure modes: contact degradation and welding of high voltage cantilevers, both of which are caused by the charging and discharging of unwanted parasitic capacitances inherent to complementary relay structures. Devices are consequently damaged by high transient current and arc discharge between contacts. Several solutions are proposed and implemented to mitigate these issues, including minimization of unwanted capacitances, optimization of metallization scheme, introduction of intermediate operation cycles intended to increase time between state changes, and prevention of welding by preemptively charging capacitors to an intermediate voltage. To this effect, a detailed study of lifetimes for both single cantilevers and logic gate structures is presented comparing a variety of metallization schemes using Pt, Ti, TiN, and W, including their multilayer combinations. These varied optimization methods yielded single cantilever lifetimes of 1.74 billion cycles on average for devices with a Ti adhesion layer, a Pt primary layer, and a W surface layer to increase durability. Using the same metallization scheme, complementary logic structures achieved 0.6 million cycles on average. These results demonstrate the viability of robust N/MEMS based complementary logic circuits for safety critical control applications.[2024-0203]","PeriodicalId":16621,"journal":{"name":"Journal of Microelectromechanical Systems","volume":"34 2","pages":"231-239"},"PeriodicalIF":2.5,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143800750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Study of Stiction Mitigation in Micromachine Structures via Naphthalene Sublimation","authors":"Hamed Nikfarjam;Sepehr Sheikhlari;Siavash Pourkamali","doi":"10.1109/JMEMS.2025.3527416","DOIUrl":"https://doi.org/10.1109/JMEMS.2025.3527416","url":null,"abstract":"Micromachined devices are susceptible to stiction failure, where suspended structures irreversibly adhere due to surface forces. This paper investigates the effectiveness and reproducibility of simple, low-cost sublimation methods to reduce stiction using a saturated naphthalene-isopropyl alcohol (IPA) solution or molten naphthalene. Six categories of test structures were fabricated on silicon-on-insulator wafers, including narrow and wide cantilevers, clamped-clamped beams, parallel clamped-clamped beams, meandering beams, and suspended proof masses. We evaluated the effectiveness of air drying, IPA rinse, supercritical point drying (CPD), naphthalene-IPA solution, and molten naphthalene by identifying the longest and least stiff intact structure released for each method. Results showed that molten naphthalene outperformed CPD for wider structures, and reproducibility was confirmed over 10 repetitions per structure and method. These cost-effective, room-temperature techniques are well-suited for mitigating stiction in larger and softer structures, enhancing accessibility and availability for MEMS fabrication. [2024-0170]","PeriodicalId":16621,"journal":{"name":"Journal of Microelectromechanical Systems","volume":"34 2","pages":"213-221"},"PeriodicalIF":2.5,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143801023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Haowen Hu;Zhiyu Sun;Chenzhe Du;Qiancheng Zhao;Yufeng Jin;Jian Cui
{"title":"Activation Model of Nano Getter for MEMS Devices Based on Sandwich Structures of Au-Porous Ti-Dense Ti Film","authors":"Haowen Hu;Zhiyu Sun;Chenzhe Du;Qiancheng Zhao;Yufeng Jin;Jian Cui","doi":"10.1109/JMEMS.2025.3526153","DOIUrl":"https://doi.org/10.1109/JMEMS.2025.3526153","url":null,"abstract":"Ti-based nano Nonevaporable getters (NEGs) have become essential materials for maintaining a long-term high vacuum in Micro-Electro-Mechanical System (MEMS) devices. However, it is still a confusing issue how to select the annealing temperature and time for the getter activation on the basis of the required activation level, excessive temperature and time will damage the MEMS devices inside the package. Therefore, the relationship between the activation temperature, activation time and activation level gains more attention since it can give guidance for the vacuum packaging process, which currently lacks an effective quantitative model to be followed. This paper introduces a simple and efficacious model for determining the activation parameters according to Fick’s diffusion law and reports a sandwich getter with an ‘Au-Porous Ti-Dense Ti’ structure based on this model to improve the getter performances. Experimental results indicate that ~50% activation level is achieved for a 3mm <inline-formula> <tex-math>$times 3$ </tex-math></inline-formula>mm sandwich-style getter with 2 hours of 300°C annealing, which is expected to enable a high vacuum for a <inline-formula> <tex-math>$1mu $ </tex-math></inline-formula>L microcavity up to 12 years. These results show close agreement with the model, proving to be valuable for optimizing the recipe of getter activation and providing an efficient way to prevent MEMS device failures.[2024-0165]","PeriodicalId":16621,"journal":{"name":"Journal of Microelectromechanical Systems","volume":"34 2","pages":"204-212"},"PeriodicalIF":2.5,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143801022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Modeling Temperature Effects in a MEMS Ring Gyroscope: Toward Physics-Aware Drift Compensation","authors":"Mehran Hosseini-Pishrobat;Erdinc Tatar","doi":"10.1109/JMEMS.2024.3524796","DOIUrl":"https://doi.org/10.1109/JMEMS.2024.3524796","url":null,"abstract":"Temperature plays an indispensable role in the long-term performance of MEMS gyroscopes, and despite extensive studies in the literature, analytical treatment of temperature effects is still an open problem. This paper, to the best of our knowledge, is the first attempt to address this gap for ring gyroscopes. We start with a superposition principle that disentangles thermal displacement fields from the gyroscope’s nominal vibration. We set forth a geometrically nonlinear variational formulation to obtain the temperature-induced stiffness matrix. We conduct temperature tests on our 3.2 mm-diameter, 58 kHz ring gyroscopes equipped with 16 capacitive stress sensors. The experimental data validate our analytical modeling in the following key aspects: 1) The model accounts for not only changes in material properties but also a less explored factor, thermal stresses. Thanks to a strain interpolation module that leverages the measured stresses, the model predicts frequency variations consistently and captures hysteresis loops arising from residual stresses. Notably, we accurately estimate the deviation of the temperature coefficient of frequency (TCF) from the expected value −30 ppm/°C (based on the widely known −60 ppm/°C dependency of Young’s modulus of silicon). 2) The model is able to capture stiffness couplings in the orders of less than 0.1 N/m (in a 7 kN/m device) and closely predicts the quadrature error and its leakage into the in-phase channel. Additionally, the model incorporates temperature variations of mechanical scale factor, drive mode’s amplitude, damping coupling, and sense mode’s phase in terms of their contribution to the in-phase error. Based on these merits, our model serves as a building block toward drift compensation algorithms encompassing the underlying physics of the temperature effects. [2024-0163]","PeriodicalId":16621,"journal":{"name":"Journal of Microelectromechanical Systems","volume":"34 2","pages":"150-163"},"PeriodicalIF":2.5,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10843100","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143800948","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":"Turnover Temperature Point Adjustment in Mechanically Coupled Single-Crystal Silicon MEMS Resonators","authors":"Yuhao Xiao;Jinzhao Han;Bowen Li;Guoqiang Wu","doi":"10.1109/JMEMS.2024.3524384","DOIUrl":"https://doi.org/10.1109/JMEMS.2024.3524384","url":null,"abstract":"This paper presents an effective approach for adjusting the zero temperature coefficient of frequency (turnover point) in mechanically coupled single-crystal silicon (SCS) microelectromechanical system (MEMS) resonators. The mechanically coupled MEMS resonators are fabricated on a heavily n-type doped SCS with a phosphorus doping concentration of around <inline-formula> <tex-math>$1.0times 10^{20}$ </tex-math></inline-formula> cm<inline-formula> <tex-math>$^ - 3 $ </tex-math></inline-formula> for achieving high turnover points. A turnover point tuning prediction model is derived, showing that the turnover point of mechanically coupled resonators can be represented as the weighted average sum of the product of the effective mass and the second order TCF of each individual resonator, along with its corresponding turnover point. By leveraging mechanical coupling between breathing-ring (BR) mode resonators and length-extensional (LE) or width-extensional (WE) mode resonators, the turnover point of mechanically coupled resonator can be purposely manipulated to above industrial temperature ranges by adjusting the dimensions of the coupled components. Such turnover temperatures can be employed in micro-oven-controlled MEMS oscillators (OCMOs) to achieve excellent frequency stability. The results offer valuable insights into optimizing the frequency-temperature characteristic of MEMS resonators in high-end timing field.[2024-0184]","PeriodicalId":16621,"journal":{"name":"Journal of Microelectromechanical Systems","volume":"34 2","pages":"134-143"},"PeriodicalIF":2.5,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143800757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Optical Characterization of Dynamic CMUTs Using Zygo Optical Profilometers: An Alternative to Laser Doppler Vibrometers","authors":"Ahmad Elshenety;Merve Mintas Kucuk;Mehmet Yilmaz","doi":"10.1109/JMEMS.2024.3524004","DOIUrl":"https://doi.org/10.1109/JMEMS.2024.3524004","url":null,"abstract":"Laser Doppler Vibrometers (LDVs) are the most common optical characterization equipment for CMUTs since LDVs characterize both static and dynamic CMUTs in terms of static deflection and resonance frequency, respectively. However, LDVs are not always available for the researchers of ultrasonic transducers. Zygo optical profilometer is also used as an optical characterization equipment for CMUTs but only for static CMUTs. In this study, we show that Zygo optical profilometers could be used to characterize dynamic CMUTs as well. The study shows that Zygo optical profilometers could be an alternative to LDVs performing both static and dynamic analyses of CMUTs. A circular CMUT cell fabricated by wafer bonding technique is characterized using Zygo optical profilometer. The first three resonance frequencies obtained by Zygo optical profilometer match the resonance frequencies obtained by impedance analyzer and ANSYS modal analysis. The equipment could also be used to characterize other ultrasonic transducers such as PMUTs and piezoelectric transducers.[2024-0171]","PeriodicalId":16621,"journal":{"name":"Journal of Microelectromechanical Systems","volume":"34 2","pages":"144-149"},"PeriodicalIF":2.5,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143800755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"2024 Index Journal of Microelectromechanical Systems Vol. 33","authors":"","doi":"10.1109/JMEMS.2024.3522404","DOIUrl":"https://doi.org/10.1109/JMEMS.2024.3522404","url":null,"abstract":"","PeriodicalId":16621,"journal":{"name":"Journal of Microelectromechanical Systems","volume":"33 6","pages":"807-828"},"PeriodicalIF":2.5,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10818783","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142905693","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}
Guijie Wang;Shenglin Hou;Lifang Ran;Jianhua Li;Bo Zhang;Xiaolong Wen;Najib Kacem;Ashwin A. Seshia
{"title":"A Weakly Coupled Tuning Fork MEMS Electric Field Sensor With High Resolution and Wide Measurement Range","authors":"Guijie Wang;Shenglin Hou;Lifang Ran;Jianhua Li;Bo Zhang;Xiaolong Wen;Najib Kacem;Ashwin A. Seshia","doi":"10.1109/JMEMS.2024.3518622","DOIUrl":"https://doi.org/10.1109/JMEMS.2024.3518622","url":null,"abstract":"High-resolution and sensitive MEMS DC electric field sensors offer the possibility for the integration of detection in multiple fields, such as atmospheric electricity, power grids and biomedical sciences. In this work, a mode-localized sensor prototype based on a double-ended tuning fork design (DETF) is presented. The theoretical derivations and lumped model simulations reveal the key performance enhancements regarding the wide measurement range and high resolution of such a coupled resonator structure. A prototype is fabricated using Silicon-On-insulator (SOI) approaches, which is further tested to achieve a sensitivity of 0.016/(kV/m), a resolution of 21.3 V/m, a measurement range of 200kV/m and a bias instability of 0.29 V/m. The metrics are improved compared to the traditional Euler beam designs and the micro-machined counterparts. This shows the capability to meet the demands for electric field sensing in modern atmospheric electricity, power grids and biomedical sciences, with enhanced sensitivity, measurement range and stability.[2024-0154]","PeriodicalId":16621,"journal":{"name":"Journal of Microelectromechanical Systems","volume":"34 1","pages":"82-91"},"PeriodicalIF":2.5,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143107188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}