Article
Chemistry, Physical
Taito Yoshie, Kenji Ishikawa, Thi-Thuy-Nga Nguyen, Shih-Nan Hsiao, Takayoshi Tsutsumi, Makoto Sekine, Masaru Hori
Summary: In the fabrication of semiconductor devices, the feature profiles of high-aspect-ratio Si trenches need to be controlled considering aspect-ratio-dependent etching. This control is achieved by a cyclic process involving sustained Ar plasma, alternating injection of C4F8 and SF6, and short-period substrate bias supply. The transient behaviors of gaseous and surface reactions are currently revealed through measurement of plasma parameters using a surface wave probe and optical emission spectroscopy. By fluorinating the etched surface during the cycle and controlling the bias-supply timing, an ARDE-free Si trench feature profile can be fabricated.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Sophie C. Patrick, Robert Hein, Paul D. Beer, Jason J. Davis
Summary: Continuous, real-time ion sensing using redox capacitance spectroscopy shows potential for sensitive and adaptable ion sensing, with the ability to provide a simple sensory readout by modulating the redox capacitance upon anion binding. This method allows for monitoring at a constant electrode polarization and tuning of sensor performance and anion binding affinity. In addition to surpassing standard voltammetric methods, this approach offers a means of modulating and monitoring host-guest interactions at redox-active interfaces.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Engineering, Electrical & Electronic
Hugo S. Alvarez, Frederico H. Cioldin, Audrey R. Silva, Luana C. J. Espinola, Alfredo R. Vaz, Jose A. Diniz
Summary: In this study, thermally evaporated aluminum was used as a hardmask to fabricate silicon microchannels using an ICP-RIE system in SF6/Ar gas mixture. The treated aluminum hardmasks demonstrated high resistance against the etching process, leading to successful fabrication of SiMCs with desired depths. SEM images showed uniform etching on the channel walls and bottom, indicating good etch uniformity for all samples.
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
(2021)
Article
Engineering, Electrical & Electronic
Thomas R. Jones, Alden Fisher, Douglas W. Barlage, Dimitrios Peroulis
Summary: This article presents a millimeter-wave solid-state waveguide switch fabricated using bulk silicon micromachining, with a photogenerated plasma within a silicon post as the switching element. The switch offers high OFF-state isolation and low insertion loss, making it suitable for high-performance millimeter-wave waveguide systems.
IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES
(2021)
Article
Chemistry, Physical
Jian Yu, Jiafeng Tang, Long Wang, Yanjie Guo, Wenyao Ma, Lei Yang, Shiyin Chen
Summary: Monitoring solution parameters is crucial in various industries and daily applications. This study introduces a dual-mode sensor combined with deep learning method to monitor multiple solution parameters effectively. By optimizing the design and increasing the dielectric constant, the sensitivity of the sensor is improved. The sensor can accurately identify solution type and concentration through capacitive and triboelectric sensing modes. Additionally, an intelligent system is developed to visualize the monitoring process.
Article
Chemistry, Analytical
Christian Riboldi, Danilo A. Carnevale Castillo, Daniele M. Crafa, Marco Carminati
Summary: To simplify the installation of sensors, we demonstrate the clamping of piezoelectric transducers and strip electrodes on plastic pipes for measurement of water flow rate, temperature, and impedance. Experimental results validate the sensors in realistic conditions, and tradeoffs in accuracy, deployment, and fabrication are discussed.
Article
Engineering, Electrical & Electronic
Virender Singh, Vijay Kumar, Ashish Saini, P. K. Khosla, Sunita Mishra
Summary: The paper discusses the design, simulation, and fabrication of a MEMS-based acceleration threshold switch that does not require power to retain its mechanical state. Experimental results were in good agreement with theoretical and simulated results, demonstrating the effectiveness of the unique design.
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
(2021)
Article
Nanoscience & Nanotechnology
Melissa J. Goodwin, Cornelis A. M. Harteveld, Meint J. de Boer, Willem L. Vos
Summary: Periodic arrays of deep nanopores in silicon are important for silicon nanophotonics. Previous studies focused on achieving deep nanopores with high aspect ratios, but resulted in structural imperfections. This study aims to realize cylindrical nanopores for better comparison with theory and simulations. By optimizing etching parameters and implementing a multistep process, cylindrical nanopores with high aspect ratios were achieved, suitable for silicon nanophotonic structures.
Article
Engineering, Electrical & Electronic
Yijing Zhang, Lin Xu, Myrthe van der Ven, Sotir Ouzounov, Mohammed Meftah, Massimo Mischi, Eugenio Cantatore, Pieter Harpe
Summary: This article proposes a front-end amplifier structure with a fast reset scheme for noncontact capacitive electrodes in ECG/heart-rate monitoring applications. The fast-reset amplifier allows for MA recovery prior to saturation, avoiding a long recovery process and signal loss. Experimental results show that the proposed amplifier outperforms the conventional structure in terms of input resistance, noise level, and MA saturation handling ability.
IEEE SENSORS JOURNAL
(2023)
Article
Chemistry, Analytical
Angela M. Baracu, Christopher A. Dirdal, Andrei M. Avram, Adrian Dinescu, Raluca Muller, Geir Uri Jensen, Paul Conrad Vaagen Thrane, Hallvard Angelskar
Summary: Metasurfaces have gained significant attention for their potential to create high-performance flat, ultrathin optical devices. Research has shown that the cryogenic and Bosch etching methods can achieve efficiencies of around 39% for silicon metalenses, despite acceptable levels of sidewall surface roughness from the Bosch DRIE process. Further process modifications are recommended to improve efficiencies in metalens fabrication.
Article
Materials Science, Multidisciplinary
D. M. Tshwane, R. Modiba, G. Govender, P. E. Ngoepe, H. R. Chauke
Summary: The adsorption of halogen molecules on Ti (110) surface was studied using a first-principle approach, revealing that the adsorption is exothermic and occurs through dissociation bonding. The HF molecule was shown to be more thermodynamically stable than the HI molecule, and halogen ions were found to favorably adsorb on the Ti (110) surface compared to halogen molecules. Adsorption energy strength was found to have a linear relationship with charge transfer, and electronic interaction was investigated through density of states and charge density difference analysis, showing electron depletion on Ti atom and charge accumulation on the halogen region.
JOURNAL OF MATERIALS RESEARCH
(2021)
Article
Chemistry, Physical
F. Hoelzel, D. Rolon, J. Bauer, J. Kober, S. Kuehne, F. Pietag, D. Oberschmidt, T. Arnold
Summary: Investigated the reactive ion beam finishing process of rapidly solidified aluminum (RSA) 501 using CF4 and N2 gasses to improve the surface roughness for UV optics. Found that surface modification can prevent grain orientation-dependent etching and adjusting ion incidence angle can reduce the protrusion of precipitates after UP-machining. Achieved a surface roughness value of Sq = 0.9 nm +/- 0.1 nm in the micro-roughness range using collimated ion beams with CF4 process gas at 40 degrees and 80 degrees angle of incidence.
SURFACES AND INTERFACES
(2023)
Review
Chemistry, Analytical
Michael Huff
Summary: This paper reviews advances in reaction-ion etching (RIE) for high-aspect-ratio microfabrication, highlighting the importance of anisotropic etching for precise control of device dimensions. Newer RIE methods have enabled deeper etches and higher aspect ratios, particularly in the development and production of silicon-based micro- and nano-machined devices.
Article
Engineering, Civil
Rahul Prasanna Kumar, David Melcher, Pietro Buttolo, Yunyi Jia
Summary: This paper presents a system that uses capacitive sensing and machine learning to monitor occupant activities in vehicle seats, such as actions and posture changes. The system employs a capacitance-sensing mat on the seat to measure capacitances and converts them into capacitance-sensing images. Machine learning algorithms are then used to recognize occupant actions and posture changes based on these images.
IEEE TRANSACTIONS ON INTELLIGENT TRANSPORTATION SYSTEMS
(2023)
Article
Engineering, Electrical & Electronic
Sina Zare Pakzad, Seckin Akinci, Mehrdad Karimzadehkhouei, B. Erdem Alaca
Summary: Silicon nanowires show great promise in various applications, particularly in the field of nanoelectromechanical systems. Optimizing their structure is key to further enhancing their performance. The current study aims to explore the limits of batch fabrication for silicon nanowires.
SEMICONDUCTOR SCIENCE AND TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Kehao Feng, Zhenghua Zhang, Guohua Bai, Xiuyuan Fan, Rongzhi Zhao, Xuefeng Zhang
Summary: This paper proposes a new method to accurately evaluate the high-frequency power loss of soft magnetic materials. Through a two-step calibration, the system is able to compensate for the phase angle discrepancy between the exciting current and induced voltage, enabling a higher power loss measurement frequency.
SENSORS AND ACTUATORS A-PHYSICAL
(2024)
Article
Engineering, Electrical & Electronic
Mingfang Kang, Tong Liu, Hongmei Sun, Lin Li, Keliang Wang
Summary: In this study, the absorption performance of ambient nitrogenous toxic gases on a monolayer of blue phosphorus phase germanium selenide (GeSe) was investigated using density-functional theory calculations. The results showed that GeSe monolayer exhibits higher sensitivity and selectivity for the hazardous gas NO.
SENSORS AND ACTUATORS A-PHYSICAL
(2024)
Article
Engineering, Electrical & Electronic
Yaqiong Niu, Zhicheng Zou, Longsheng Cheng, Chaofeng Ye
Summary: This paper proposes a novel method to stabilize the laser diode output using a close-loop control with two feedbacks. The proposed method performs better for long-time operations.
SENSORS AND ACTUATORS A-PHYSICAL
(2024)
Article
Engineering, Electrical & Electronic
Jiajie Li, Ying Liu, Zhen Chai, Qian Cao, Renjie Li, Yueyang Zhai
Summary: This study proposed an efficient and high-quality beam-splitting method based on a diffractive optical element, enabling multichannel SERF atomic magnetometers to achieve ultra-high consistency and sensitivity. It has significant applications in array biomagnetic measurement systems.
SENSORS AND ACTUATORS A-PHYSICAL
(2024)
Article
Engineering, Electrical & Electronic
E. Oliveira, C. Doering, H. Fouckhardt
Summary: With the development of Lab on a chip technology, fluid management using dispersed droplets has become an important approach. Electrowetting on dielectric (EWOD) is one method for droplet actuation, but it requires prior definition of droplet positions. Optoelectrowetting (OEW) goes further by allowing changes in electrical parameters through impinging light spots, without the need for predefined droplet positions. This study re-evaluates the key parameters of OEW and explores their effects on droplet actuation using numerical optimization methods.
SENSORS AND ACTUATORS A-PHYSICAL
(2024)
Article
Engineering, Electrical & Electronic
Haipeng Wang, Zhiguo Wang, Gancheng Zhu, Shuai Zhang
Summary: A novel capacitive proximity skin was developed to improve the performance of robotics in handling liquid-filled containers. This skin features a flexible structure that can adapt to different grippers and seamlessly integrate with Robot Operating System. Experimental results demonstrated that this proximity skin achieved data-lossless detection and contactless measurement of liquid level, making it suitable for grasping operations.
SENSORS AND ACTUATORS A-PHYSICAL
(2024)
Article
Engineering, Electrical & Electronic
Tsenguun Byambadorj, Xiangyu Zhao, Yutao Qin, Yogesh B. Gianchandani
Summary: In this research, a monolithically microfabricated Knudsen pump (KP) without suspended membranes was presented. These pumps offer improved mechanical robustness, wider process window, and simplified microfabrication process compared to previous designs. The experimental results matched the modeling results well, indicating the potential for monolithic integration onto complex lab-on-a-chip systems.
SENSORS AND ACTUATORS A-PHYSICAL
(2024)
Article
Engineering, Electrical & Electronic
Hamed Karami, Saeed Karami Chemeh, Vahid Azizi, Hooman Sharifnasab, Jose Ramos, Mohammed Kamruzzaman
Summary: Aroma is a significant quality trait for pharmaceutical plants and their products, indicating the quality of the raw material. An electronic nose is an efficient approach for identifying and evaluating the aroma of essential oils. In this study, tarragon was dried at different temperatures and air velocities, and the purity of tarragon essential oil was evaluated using an electronic nose. Multivariate data analysis and artificial neural networks modeling were employed to quantify and classify the obtained essential oils.
SENSORS AND ACTUATORS A-PHYSICAL
(2024)
Article
Engineering, Electrical & Electronic
Xiaoyang Duan, Dan Xu, Wenjun Jia, Ran Li, Bohao Sun, Ruitian Yan, Wenjie Zhao
Summary: Flower-like WO3/WS2 heterojunction materials constructed via a low-temperature in-situ oxidation method exhibit significant improvements in the detection of NO2 gas in gas sensors, along with good selectivity and reproducibility.
SENSORS AND ACTUATORS A-PHYSICAL
(2024)
Article
Engineering, Electrical & Electronic
Peng Yu, Mengyang Zhang, Manqi You, Yuxi Gao, Landong Xiao, Yan Peng, Jingxia Lai, Zhouzhao Shi, Siwei Luo, Gencai Guo, Gang Guo
Summary: Recent studies have shown that two-dimensional Janus transition metal dichalcogenides (TMDs) have great potential for applications in gas sensors. By conducting first principles calculations, this study explores the potential application of Pd-doped monolayer HfSeS as gas sensor materials for detecting CO, CO2, NH3, and NO. The results demonstrate the good thermodynamical stability and reversible adsorption of these molecules on both pristine and Pd-doped HfSeS, with Pd-doped HfSeS showing higher sensitivity towards NO due to its metallic behavior upon NO adsorption.
SENSORS AND ACTUATORS A-PHYSICAL
(2024)
Article
Engineering, Electrical & Electronic
Jinlan Yang, Linjiao Li, Jun Huang, Quan Zhang, Hiba Affane
Summary: This study proposes a method for large-scale aggregation of micro-particles by creating a vortex region using low-frequency oscillation. Experimental results show that this method can achieve a large aggregation area and has the advantages of low cost and low power consumption.
SENSORS AND ACTUATORS A-PHYSICAL
(2024)
Article
Engineering, Electrical & Electronic
Jitendra Singh, Saurabh Kumar Gupta, Vinita
Summary: In this investigation, a Surface Acoustic Wave (SAW) formalin gas sensor was explored for low-level formalin gas sensing applications. The sensor showed stable response and high sensitivity to formalin gas concentration, making it a reliable and useful sensor for room temperature operations.
SENSORS AND ACTUATORS A-PHYSICAL
(2024)
Article
Engineering, Electrical & Electronic
Junyao Wang, Yahao Liu, Huan Liu, Qi Hou, Jianxin Xu, Hongxu Pan, Jingran Quan, Yansong Chen, Hanbo Yang, Lixiang Li
Summary: A flexible electrode with a serpentine-shaped tetra-chiral structure was designed to improve the mechanical properties and prevent mechanical fracture of flexible electrodes. The research demonstrated that this structure reduced the maximum tensile stress by 87.19% compared to the existing tetra-chiral structure. The flexible electrode remained conductive even at a strain of 70% and showed resistance values of 5 ohm and 4.4 ohm at a bending angle of 180 degrees and after 1000 fold cycles. Furthermore, the flexible electrodes showed great potential in biological signal monitoring, particularly in collecting ECG and pulse signals.
SENSORS AND ACTUATORS A-PHYSICAL
(2024)
Article
Engineering, Electrical & Electronic
Taihao Chen, Yong Fang, Mengru Zhu, Zhiwei Zhao, Wei Lei, Zhuoya Zhu, Helong Jiang
Summary: Flexible dual-spectral carbon nanodots/flexible n-silicon heterojunction photodetectors with high responsivity and detectivity are reported. These detectors show photo response in UV illumination and only in forward bias under visible illumination. The photocurrent of the device remains high even under bending strain.
SENSORS AND ACTUATORS A-PHYSICAL
(2024)
Article
Engineering, Electrical & Electronic
M. S. Sikandar Bathusha, Israr Ud Din, Rehan Umer, Kamran A. Khan
Summary: Graphene-based nanomaterials are used as embedded sensors to monitor fracture behavior in composite structures. This study investigates the in-situ crack propagation and fracture behavior in a glass fiber reinforced polymer composite using embedded reduced graphene oxide coated fabrics and highly conductive graphene nanoplatelet paper.
SENSORS AND ACTUATORS A-PHYSICAL
(2024)