Article
Chemistry, Analytical
Hongbo Feng, Jiabin Zhao, Chengsi Zhou, Mingxin Song
Summary: A novel RF MEMS switch design with two support pillars was proposed in this study to slow down the fall of the beam membrane and reduce the impact velocity. Simulation analysis was conducted to determine the optimal height and positioning of the support pillars for achieving a balance between impact velocity and pull-in time.
Article
Engineering, Electrical & Electronic
K. Girija Sravani, T. Lakshmi Narayana, Koushik Guha, K. Srinivasa Rao
Summary: This paper analyzes the impact of the dielectric layer and beam membranes on the performance of the shunt capacitive RF MEMS switch. By incorporating non-uniform meanders and a 50 nm AlN dielectric thin film, the actuation voltage is reduced and isolation is improved. The switch, with optimized design parameters, demonstrates suitable performance for Ka-band applications.
MICROSYSTEM TECHNOLOGIES-MICRO-AND NANOSYSTEMS-INFORMATION STORAGE AND PROCESSING SYSTEMS
(2021)
Article
Telecommunications
Mallikharjuna Rao Sathuluri, G. Sasikala
Summary: This paper presents the design of a reconfigurable microstrip patch antenna using RF MEMS switches. The antenna switches between different frequency bands with improved performance, offering an actuation voltage of 4.5 V, insertion losses of -0.55 dB, and isolation losses of -51 dB. The study also analyzes the impact of materials and micromechanical structures on enhancing pull-in voltage.
WIRELESS PERSONAL COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Joaquin Bermejo, Jaime Colchero, Elisa Palacios-Lidon
Summary: Conductive polymers have fundamental relevance and novel technological applications in organic optoelectronics. The photophysical and transport properties of conductive polymers depend on molecular arrangement, requiring nanoscale characterization to understand optoelectronic processes.
Article
Energy & Fuels
C-S Jiang, D. Albin, M. Nardone, K. J. Howard, A. Danielson, A. Munshi, T. Shimpi, C. Xiao, H. R. Moutinho, M. M. Al-Jassim, G. Teeter, W. Sampath
Summary: This paper investigates the stability and electric field distribution of CdTe devices with a structure of TCO/MZO/CdSeTe/CdTe/backcontact. The results show reversible transitions between the light-soak state (LSS) and the dark-soak state (DSS), but irreversible degradation occurs after long-hour light soaking at an elevated temperature. The electric field profiles at different states reveal the presence of a buried homojunction (BHJ) in the LSS and an increased electric field near the MZO/CdSeTe interface at the DgS.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2022)
Article
Nanoscience & Nanotechnology
Ryo Izumi, Masato Miyazaki, Yan Jun Li, Yasuhiro Sugawara
Summary: The recently proposed high-low Kelvin probe force microscopy (KPFM) allows for the evaluation of semiconductor interface states with high spatial resolution using high and low AC bias frequencies. This is important for assessing the energy spectrum of interface state density in semiconductor devices. In this study, a method called high-low Kelvin probe force spectroscopy (high-low KPFS) is proposed, which measures the interface state density inside semiconductors using high and low-frequency AC bias voltages. Preliminary experiments on ion-implanted silicon surfaces confirmed the dependence of electrostatic force on AC bias voltage frequency and obtained the interface state density.
BEILSTEIN JOURNAL OF NANOTECHNOLOGY
(2023)
Article
Energy & Fuels
Christian Kameni Boumenou, Amala Elizabeth, Finn Babbe, Alice Debot, Harry Moeenig, Alex Redinger
Summary: The study investigated the buried MoSe2/CuInSe2 interface of stoichiometric absorbers in thin film solar cells, revealing differences in local density of states compared to the front-side properties. This sheds new light on the complex interface formation in CuInSe2-based thin film solar cells grown under Cu-rich conditions.
PROGRESS IN PHOTOVOLTAICS
(2021)
Article
Physics, Applied
Yushan Chen, Wenbin Xu, Liang Jiang, Linmao Qian
Summary: This study developed a probe switching unit with electrical measurement for in situ multifunctional characterization in nanotribology research, which provides important insights.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Nanoscience & Nanotechnology
Jill Serron, Albert Minj, Valentina Spampinato, Alexis Franquet, Yevhenii Rybalchenko, Marie-Emmanuelle Boulon, Steven Brems, Henry Medina Silva, Yuanyuan Shi, Benjamin Groven, Renan Villarreal, Thierry Conard, Paul van der Heide, Thomas Hantschel
Summary: This study investigates the rapid intercalation of water vapor at the interface of transition metal dichalcogenides (TMDs) and sapphire, as well as between two TMD monolayers, and examines its impact on their electrical properties. The findings reveal that water vapor can intercalate rapidly within a few minutes and show partial reversibility under (ultra)-high vacuum conditions. Complete desorption of intercalated water clusters significantly enhances the electronic properties of TMDs, but also indicates that the characterization of TMD samples is significantly affected by the presence of water intercalation in air, inert environments, and even vacuum. Moreover, the study highlights a correlation between water intercalation and the presence of defects, contributing to the gradual degradation of TMDs as they age.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Shangzhi Gu, Wenyu Liu, Shuo Mi, Guoyu Xian, Jiangfeng Guo, Fei Pang, Shanshan Chen, Haitao Yang, Hong-Jun Gao, Zhihai Cheng
Summary: In this study, the twist angle-dependent work functions of twisted bilayer graphene (tBLG) were investigated using Kelvin probe force microscopy (KPFM) and Raman spectroscopy. The surface potentials of Bernal-stacked multilayer graphene were measured to determine the relationship between twist angle and surface potential. It was found that the work function of tBLG decreases and tends to saturate with increasing number of layers. Controlled annealing process showed that tBLG transforms into Bernal-stacked bilayer graphene. This research provides valuable insights into the twist angle-dependent surface potentials and electronic properties of tBLG.
Article
Chemistry, Physical
Hwi Je Woo, Seongchan Kim, Young-Jin Choi, Jeong Ho Cho, Seong Heon Kim, Young Jae Song
Summary: The work function of graphene devices on SiO2 substrates is studied using Kelvin probe force microscopy, revealing gate voltage-dependent work-function hysteresis. The inhomogeneous distribution of chemical species at the graphene/SiO2 interface leads to varying degrees of hysteresis across different positions on the graphene.
Article
Chemistry, Multidisciplinary
Devon S. Jakob, Nengxu Li, Huanping Zhou, Xiaoji G. Xu
Summary: This article introduces a novel method to generate Coulombic force in KPFM, increasing the spatial resolution to approximately 25 nm. By integrating PiFM, high spatial resolution chemical distributions and surface potential maps can be obtained concurrently. This is expected to facilitate characterizations of nanoscale electrical properties of photoactive materials, semiconductors, and ferroelectric materials.
Article
Chemistry, Multidisciplinary
Minwoo Lee, Eunyoung Choi, Arman Mahboubi Soufiani, Jihoo Lim, Moonyong Kim, Daniel Chen, Martin Andrew Green, Jan Seidel, Sean Lim, Jincheol Kim, Xinchen Dai, Robert Lee-Chin, Bolin Zheng, Ziv Hameiri, Jongsung Park, Xiaojing Hao, Jae Sung Yun
Summary: This study presents an effective strategy to improve the performance of halide perovskite-based PV devices by using a hole-selective layer formed by PEAI salt, achieving high efficiency and stability under different light conditions.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Engineering, Electrical & Electronic
Kanaka Joy, Anurag Swarnkar, M. S. Giridhar, Amitava DasGupta, Deleep R. Nair
Summary: A radio frequency microelectromechanical system capacitive shunt switch with metal-to-metal contact was designed, fabricated, and tested to achieve very low insertion loss (<0.2 dB) for high frequencies. The switch utilizes two identical parallel side beams without overlapping the signal line, effectively eliminating self-actuation issues at high RF power. The measured isolation of the switch exceeds 40 dB at the resonant frequency, which can be easily tuned by adjusting the length of a thin floating metal layer beneath the signal line.
JOURNAL OF MICROMECHANICS AND MICROENGINEERING
(2023)
Article
Nanoscience & Nanotechnology
Ana Senkic, Antonio Supina, Mert Akturk, Christoph Gadermaier, Margherita Maiuri, Giulio Cerullo, Natasa Vujicic
Summary: Using non-invasive techniques, we investigated the spatial distribution of defects in as-grown CVD MoS2 monolayers and found that increasing the growth temperature reduces the concentration of defects and changes their spatial distribution and type, leading to effects on the electronic and optical properties of the sample.
Article
Nanoscience & Nanotechnology
F. Mortreuil, L. Boudou, K. Makasheva, G. Teyssedre, C. Villeneuve-Faure
Summary: The study focuses on the properties of plasma deposited SiOxNy dielectric layers at different thicknesses, finding that the thickness of the dielectric film affects the charging phenomena, but has a weak influence on the injected charge amount and decay dynamics.
Article
Engineering, Electrical & Electronic
Dominique Henry, Timothee Marchal, Julien Philippe, Patrick Pons, Herve Aubert
Summary: This article presents a method for wirelessly querying and identifying multiple passive pressure sensors in an industrial environment with a reading range of at least 4 m. The 3-D beamscanning of the scene is performed using a 24-GHz FM-CW radar, with diverse electric field polarizations. The use of cross-polarized electric fields combined with radar imagery technique enables remote interrogation of passive pressure sensors up to 17.7 m away, with measurement uncertainty on pressure discussed.
IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES
(2021)
Article
Chemistry, Physical
M. Mitronika, C. Villeneuve-Faure, F. Massol, L. Boudou, W. Ravisy, M. P. Besland, A. Goullet, M. Richard-Plouet
Summary: TixSi1-xO2 thin films were deposited using low pressure PECVD with tunable properties obtained by varying precursor flow rates. Surface chemical composition was analyzed by XPS, showing increased surface roughness with higher Titanium content. Electrical properties investigation at nanoscale revealed that a small amount of Titanium can improve dielectric permittivity and charge transport behavior.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Applied
Mathieu Chalnot, Anthony Coustou, Herve Aubert, Patrick Pons, Maylis Lavayssiere, Alexandre Lefrancois, Jerome Luc
Summary: This paper discusses the limitations of wired transmission of blast pressure signals delivered by sensors and proposes a new wireless solution for dynamic measurement. Experimental results confirm that the measurement bandwidth of the wireless setup is not limited by distance, paving the way for dynamic measurement of blast pressure variations during explosions.
PROPELLANTS EXPLOSIVES PYROTECHNICS
(2021)
Review
Physics, Applied
Gilbert Teyssedre, Feihu Zheng, Laurent Boudou, Christian Laurent
Summary: The trapping phenomena in insulating materials play a crucial role in controlling transport properties, with traps either assisting transport or leading to long-lasting charge storage depending on energy depth. Various techniques are discussed for probing the energetics of traps, focusing on methods involving thermal or optical excitation coupled with electrical or luminescence response. The review also emphasizes the differences in response obtained through various approaches and the impact of distributed trap depths on charge recombination.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Chemistry, Analytical
Julien Philippe, Muriel Ferry, Samuel Charlot, Sandrine Assie, Aurelie Lecestre, Guillaume Libaude, Andre Ferrand, Patrick Pons, Herve Aubert
Summary: This paper presents the design, fabrication, and performance measurement of a passive microelectromechanical transducer for the wireless monitoring of high irradiation doses in nuclear environments. The sensor is composed of high-density polyethylene material sealed inside a cavity, and its design allows for the estimation of radiation dosage through the deflection of a dielectric membrane.
Article
Physics, Applied
C. Rigoudy, K. Makasheva, M. Belhaj, S. Dadouch, G. Teyssedre, L. Boudou
Summary: This study examines the electron emission phenomenon from very thin dielectric layers, finding that there is an atypical dip in the TEEY curve for primary electrons with energy around 1 keV, which is closely related to layer thickness. The effects of SiO2 layer thickness, incidence angle of primary electrons, and applied external electric field on the TEEY curves are reported.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Chemistry, Analytical
Mathieu Chalnot, Patrick Pons, Herve Aubert
Summary: This article presents a methodology to determine the required bandwidth for accurately measuring and estimating the overpressure magnitude at the front of a blast wave.
Article
Engineering, Electrical & Electronic
John Theocharis, Spiros Gardelis, George Papaioannou
Summary: This study investigates the impact of ambient on the field emission of rigid MEMS capacitive structure and the resulting breakdown induced damage. The findings include asperities burning due to Joule heating and explosive breakdown, which leads to mirror-like craters on the cathode and anode electrodes. In vacuum, there is a linear relation between crater diameter and breakdown current. However, in ambient atmosphere, breakdown results in large amplitude current oscillations and extended damage on both electrodes.
IEEE TRANSACTIONS ON DEVICE AND MATERIALS RELIABILITY
(2022)
Article
Chemistry, Analytical
Kevin Sanchez, Bilel Achour, Anthony Coustou, Aurelie Lecestre, Samuel Charlot, Maylis Lavayssiere, Alexandre Lefrancois, Herve Aubert, Patrick Pons
Summary: In this paper, a new ultra-fast sensor is designed for accurately measuring static overpressure peaks in blast wave experiments. The sensor uses piezo-resistive gauges and has a response time lower than a few microseconds.
Article
Chemistry, Analytical
Maylis Lavayssiere, Alexandre Lefrancois, Bernard Crabos, Marc Genetier, Maxime Daudy, Sacha Comte, Alan Dufourmentel, Bruno Salsac, Frederic Sol, Pascal Verdier, Patrick Pons
Summary: This paper proposes two ways to improve pressure measurement in air-blast experimentations for close-in detonations. Firstly, a custom-made pressure probe sensor with a modified tip material is presented, which can measure high-frequency pressure signals. Secondly, the paper introduces a deconvolution method using the pencil probe transfer function determination with a shock tube, and demonstrates its effectiveness on experimental results.
Article
Chemistry, Analytical
Antony Coustou, Alexandre Lefrancois, Patrick Pons, Yohan Barbarin
Summary: This study investigated the capacitive effect and electromagnetic coupling induced by impact experiments with a gas gun or powder gun on the measurement chain. The experiment results showed reduced bandwidth and increased noise on the signals. With modeling and calculations, the study reproduced these effects and identified the capacitive effect in the sample.
Proceedings Paper
Engineering, Electrical & Electronic
T. Marchal, D. Henry, P. Pons, H. Aubert
Summary: This paper reports the remote measurement of pressure using a novel microfluidic passive sensor and Radar technology. The sensor includes a microfluidic band-pass filter and cross-polarized antennas to enhance the measurement range. The filter is 3D-printed and shows a high full-scale measurement range and sensitivity for pressure ranging from 350 mbar to 640 mbar.
2021 IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM (IMS)
(2021)
Article
Nanoscience & Nanotechnology
C. Djaou, C. Villeneuve-Faure, K. Makasheva, L. Boudou, G. Teyssedre
Summary: Dielectric nanocomposite materials play a crucial role in electrical engineering applications, and this study investigates the impact of silver nanoparticles on electric field distribution and charge injection. Results show that higher temperatures lead to increased charge injection and faster lateral charge spreading in the nanocomposites.
Proceedings Paper
Engineering, Electrical & Electronic
Dominique Henry, Patrick Pons, Herve Aubert
Summary: This paper investigates the wireless interrogation of chipless and passive mechanical sensors using a range-Doppler imaging algorithm. A remote detection algorithm is proposed to estimate the reading range and Doppler harmonics embedded in the backscattered electromagnetic signal for accurate estimation of illuminance in cluttered environments at long reading ranges of at least 3.5m.
2021 15TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP)
(2021)
Article
Engineering, Electrical & Electronic
Zhiqiang Wang, Siyang Dai, Yao Zhao, Guofeng Li, Bing Ji, Volker Pickert, Bowen Gu, Shuai Ding
Summary: This paper proposes a lumped-charge model for IEGT single chip, considering the effect of carrier injection enhancement in the emitter. The parasitic inductance of the parallel branches in PP-IEGT is extracted using Ansys simulation, and the validity of Ansys simulation is verified. Furthermore, the switching inconsistency is evaluated by combining the electrical model and the effect of mutual inductance, and it is found that mutual inductance is an important factor influencing electrical parameter distribution.
MICROELECTRONICS RELIABILITY
(2024)
Article
Engineering, Electrical & Electronic
Sankha Subhra Ghosh, Surajit Chattopadhyay, Arabinda Das, Nageswara Rao Medikondu, Abdulkarem H. M. Almawgani, Adam R. H. Alhawari, Sudipta Das
Summary: This article describes a method for identifying the IGBT switch breakdown failure in a 3-phase, 3-level Voltage Source Converter linked to the photovoltaic grid. Comparative learning has been used to detect the specific parameter suitable for the detection of the failure.
MICROELECTRONICS RELIABILITY
(2024)
Article
Engineering, Electrical & Electronic
Milad Khajehvand, Henri Seppanen, Panthea Sepehrband
Summary: Using SEM/EDX analysis, microscale fracture at the bond-pad is detected during the wedge bonding process of Cu wire to a Cu or Al substrate. It is observed that the fracture of the bond leads to the formation of a bulge on the wire and a cavity in the substrate, causing fracture in the original substrate. 3D optical profiler reveals that the depth, radius, and surface area of the cavity increase with bond time for a constant bond force and power. These metrics are suggested as new factors for optimizing the wedge bonding process. The optimal bonding parameters should maximize the cavity's surface area (related to bond's pull force) while minimizing the cavity's depth relative to the substrate's thickness to avoid substrate damage. Furthermore, Molecular Dynamics simulations propose a potential plastic deformation mechanism for bond-pad damage, suggesting the benefits of using a small-grain-sized substrate, low transducer's vibration amplitude, and high transducer's frequency to minimize the cavity's depth.
MICROELECTRONICS RELIABILITY
(2024)
