Cylindrical Capacitor Research Articles

Performance improvement of HfO2-based ferroelectric with 3D cylindrical capacitor stress optimization

To meet commercialization requirements, the distributions of materials in hafnium-based ferroelectric devices—including their phase and orientation—need to be controlled. This article presents a method for improving the ferroelectric phase ratio and orientation by adjusting the stress distribution of the annealing structure in a three-dimensional capacitor. In such a structure, stress can be applied in three directions: tangential, axial, and radial; there are, thus, more ways to regulate stress in three-dimensional structures than in two-dimensional structures. This work sought to clarify the role of the stress direction on the proportions and orientations of ferroelectric phases. The results of stress simulations show that a structure with an internal TiN electrode, but no filling provides greater axial and tangential stresses in the hafnium-oxide layer. In comparison with the case of the hole being filled with tungsten, the proportion of the O phase is increased by approximately 20%, and in experiments, the projection of the polarization direction onto the normal was found to be increased by 5%. Axial and tangential stresses are regarded to be beneficial for the formation of the O phase and for improving the orientation of the polarization direction. This work provides a theoretical basis and guidance for the three-dimensional integration of hafnium-based ferroelectric materials.

Broadband dark matter axion detection using a cylindrical capacitor

Cosmological axions/axion-like particles can compose a significant part of dark matter; however, the uncertainty of their mass is large. Here, we propose to search the axions using a cylindrical capacitor, in which the static electric field converts dark matter axions into an oscillating magnetic field. Due to the odd CPs, the axions couple to the electric field differently compared to the magnetic field. The axion couples to the electric field via a derivative that carries spatial information of incoming dark matter flux, while the coupling to the magnetic field depends on the dark matter density. This difference could be helpful in searching the axions and studies of the integrity of the theory, especially when the axions are very light, in which case the magnetic field-induced signal is DC-like. Orientation dependence could also be used to reduce the kinetic fluctuation-induced noise when multiple detectors operate simultaneously. In addition, a cylindrical setup shields the electric field to the laboratory and encompasses the axion-induced magnetic field within the capacitor. The induced oscillating magnetic field can then be picked up by a sensitive magnetometer. Adding a superconductor ring-coil system into the scheme can further boost the sensitivity and maintain the axion dark matter inherent bandwidth. This proposed setup could be capable of wide mass range searches.

Determination of the capacitance of capacitor with orthotropic dielectric material

AbstractThe paper deals with the capacitance of cylindrical two-dimensional capacitor which consists of Cartesian orthotropic dielectric material. The determination of the capacitance of capacitor with orthotropic dielectric material by a suitable coordinate transformation is reduced to the computation of capacitance of an isotropic capacitor. It is proven that the capacitance of a Cartesian orthotropic capacitor can be obtained in terms of an isotropic capacitor whose dielectric constant is the geometric mean of the dielectric constant of the orthotropic capacitor.

The Design and Experimentation of a Corn Moisture Detection Device Based on Double Capacitors.

Detecting the moisture content of grain accurately and rapidly has important significance for harvesting, transport, storage, processing, and precision agriculture. There are some problems with the slow detection speeds, unstable detection, and low detection accuracy of moisture contents in corn harvesters. In that case, an online moisture detection device was designed, which is based on double capacitors. A new method of capacitance complementation and integration was proposed to eliminate the limitation of single data. The device is composed of a sampling mechanism and a double-capacitor sensor consisting of a flatbed capacitor and a cylindrical capacitor. The optimum structure size of the capacitor plates was determined by simulation optimization. In addition to this, the detection system with software and hardware was developed to estimate the moisture content. Indoor dynamic measurement tests were carried out to analyze the influence of temperature and porosity. Based on the influencing factors and capacitance, a model was established to estimate the moisture content. Finally, the support vector machine (SVM) regressions between the capacitance and moisture content were built up so that the R2 values were more than 0.91. In the stability test, the standard deviation of the stability test was 1.09%, and the maximum relative error of the measurement accuracy test was 1.22%. In the dynamic verification test, the maximum error of the measurement was 4.62%, less than 5%. It provides a measurement method for the accurate, rapid, and stable detection of the moisture content of corn and other grains.

Bounding Formulae for the Capacitance of a Cylindrical Two-dimensional Capacitor with Cartesian Orthotropic Dielectric Material

This paper addresses the evaluation of a two-dimensional cylindrical capacitor featuring homogeneous Cartesian anisotropic dielectric material. The development of a bounding formula forms the crux of the investigation and is grounded in the principles of the Cauchy-Schwarz inequality, a mathematical concept widely acknowledged for establishing relationships between different mathematical entities. In the course of this study, a dual-sided bound is systematically derived for the circular cylindrical two-dimensional capacitor through the application of well-established inequality relations. These bounds play a pivotal role in setting limits on the capacitance of the system, providing valuable insights into its electrical behavior.

Light dark matter axion-wind detection with a static electric field

We explore the axionic dark matter search sensitivity with a narrow-band detection scheme aimed at the axion-photon conversion by a static electric field inside a cylindrical capacitor. An alternating magnetic field signal is induced by effective currents as the axion dark matter wind flows perpendicularly through the electric field. At low axion masses, such as in a KKLT scenario, front-end narrow band filtering is provided by using LC resonance with a high Q factor, which enhances the detectability of the tiny magnetic field signal and leads to thermal noise as the major background that can be reduced under cryogenic conditions. We demonstrate that high gaγ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$g_{a\\gamma }$$\\end{document} sensitivity can be achieved by using a strong electric field E∼\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$E\\sim $$\\end{document}MVm-1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^{-1}$$\\end{document}. The QCD axion theoretical parameter space would require a high E∼\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$E\\sim $$\\end{document} GVm-1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^{-1}$$\\end{document} field strength. Using the static electric field scheme essentially avoids exposing the sensitive superconducting pickup to an applied laboratory magnetic field.

A design strategy for performance improvement of capacitive sensors for in-flight oil-level monitoring aboard helicopters

Cylindrical capacitors are largely employed in avionic industry as contact submerged probes of level sensors for in-flight oil-level monitoring for many reasons: their high robustness, their long MTBF (Mean Time Between Failures), maintenance-free character, virtually infinite resolution readings and last, relatively low cost. However, the cylindrical capacitors suffer from low sensitivity mainly due to small oil permittivity. This is clearly a disadvantage which collides with the ever-increasing demand for higher static and dynamic performances. To improve that, the approach adopted here consists in tweaking the conventional design of this kind of sensors guided by the study of their limitations in terms of static errors and poor responsiveness caused by phenomena of capillarity, high viscosity, and vibrations. Indeed, sensitivity doubling is proved to be achieved without compromising the indispensable former qualities. This is shown by the results of electrostatic, fluid mechanics, and structural dynamics analyses presented with enough details. Numerical simulations have been carried out and are here presented to confirm results. To summarize, with respect to the conventional capacitive level sensors currently available on the market, the achievements of the proposed design are i) an improved sensitivity that, for engine oils, is greater than 700pF/m, ii) a lower cost even though extra-costs for surface perforation must be accounted for, iii) cancellation of systematic error due to capillary phenomena and iv) improved dynamic response. Also, accurate experimental verifications are being carried out and will be shared in a future paper.

Development of the theory and schematic solutions of the gyroscope based on superconducting quantum interferometers

Based on the principle of equivalence of the general theory of relativity and the definition of the non-Euclidean metric of space in a non-inertial frame of reference associated with rotation, a geometric (topological) phase is found that occurs when traversing any closed loop. This approach made it possible to establish a deep physical analogy between various wave effects (both classical and quantum) in closed waveguides that arise under the conditions of their rotation. Due to the coherence of the wave function of spinless charge carriers (Cooper pairs of conduction electrons with oppositely directed spins) in superconductors in the ground quantum state (superconducting state), the appearance of a geometric phase in closed loops under rotation conditions can lead to interference effects in the presence of weak bonds in the loop. To register interference effects, it was proposed to use superconducting quantum interferometers placed in the electric field of a cylindrical or spherical capacitor. In accordance with the general theory of the geometric phase of rotation, the study obtained the basic relations between the geometric phase of rotation and the phase of the wave function induced by an external magnetic field, and an estimate of their values was obtained for acceptable values of the angular velocity of rotation, dimensions of superconducting quantum interferometers, and voltages on the capacitor. The errors in measuring the magnetic flux during the rotation of the measuring complex are determined. Taking into account the dependence of the magnitude of the geometric phase of rotation on the voltage across the capacitor and the size of the superconducting quantum interferometers, and also taking into account the specific range of angular velocities of rotation, the sensitivity of superconducting quantum interferometers to the angular velocity can be regulated by a rational choice of these parameters. Based on the results obtained, a new method for measuring magnetic fields was proposed using two superconducting quantum interferometers with different values of areas bounded by closed contours under conditions of rotational movements, which makes it possible to compensate for the disturbing influence of rotations on magnetic measurements, as well as to simultaneously determine the magnetic induction and angular velocity of rotation.

Design and Characterization of a Mckibben Pneumatic Muscle Prototype with an Embedded Capacitive Length Transducer

The McKibben muscle types are pneumatic actuators known to be intrinsically safe for their high power-to-weight ratio. For these reasons, they are suitable for robotic, biomechanical, and medical applications. In these application fields and, above all, in collaborative robotics, where safety must be ensured for human–robot interactions, the values of pressure, force, and length are necessary and must be continuously monitored and controlled. Force and pressure transducers are commercially available to be integrated into a McKibben muscle type. On the contrary, no commercial-length transducers can be adopted. This work presents a novel McKibben muscle prototype with an embedded capacitive-length transducer. The latter is a cylindrical capacitor made of a telescopic system composed of two tubes: one of its ends is connected to the muscle. A change in the length of the muscle causes a proportional change in the transducer capacitance. The paper reports in detail on the working principle of McKibben’s muscle, its fabrication, characterization, and validation of four prototype capacitive transducers. The results achieved from the experimental activities demonstrate that it is possible to control the variations of the muscle length relative to its elongation and compression for values less than 1 mm. This is the consequence of the ability to measure the transducer capacitance with a typical statistical relative indetermination better than 0.25%, which is a figure of merit for the reliability and mechanical and electrical stability of the proposed McKibben muscle prototype. Moreover, it has been demonstrated that the transducer capacitance as a function of the muscle length is linear, with maximum deviations from linearity equal to 2.44% and 5.22% during the muscle elongation and compression, respectively.

Practical realization and design of three-cascade prism mass analyzer for isotopic analysis of H-He mixtures using MS-platform technology

The paper presents the construction of a mass analyzer for the analysis of hydrogen-helium mixtures based on a magnetic prism using a three-stage circuit that includes two cylindrical capacitors. The choice of an ion-optical scheme that provides a high resolution of 3300, which is necessary for the separation of all nuclides formed during the analysis of hydrogen-helium mixtures, is justified. It is shown that the innovative «MS-Platform» technology makes it possible to ensure high assembly accuracy of the elements of the prism mass analyzer ion-optical circuit, which is necessary to realize all the advantages of a prism mass spectrometer compared to sector ones.

Integrated sub-micron vacuum gaps in semiconductor devices

We present characterization results of integrated vacuum gaps in semiconductors and report the highest breakdown field of dielectric layers ever recorded within microfabricated semiconductor devices. Difficulties associated with the characterization of vacuum gaps in the presence of high electric fields could be overcome by using cylindrical capacitors with silicon electrodes that were manufactured with standard semiconductor technology. With this approach, breakdown fields of up to 6 × 109 V/m were achieved. The vacuum gaps of 175(5) nm were significantly smaller than the mean free path of electrons within the gap such that a breakdown due to avalanche discharge was avoided. As the voltage was increased, initially a field emission current was observed that followed a Fowler–Nordheim tunneling behavior. The tunneling current started to increase at voltages about four times greater as compared to equivalent dielectric layers of silicon oxide. At higher voltages, a mechanical breakdown occurred, where the pillars that formed the central electrode of the capacitor snapped due to electrostatic forces. We provide characteristics of thin vacuum layers, which could be useful for device design in micro- and nanoelectromechanical systems as well as semiconductor devices.

INCONSISTENCIES IN EM THEORY - THE KELVIN POLARIZATION FORCE DENSITY CONTRADICTION

Calculations of resultant electrostatic force on a charged spherical or cylindrical capacitor with two sectors of different dielectrics, based on the classical formulas of electrostatic pressure, Kelvin polarization force density, and Maxwell stress tensor predict a reactionless force that violates Newton’s 3rd law. Measurements didn’t confirm the existence of such a reactionless thrust, thus there is an apparent inconsistency in the classical EM theory that leads to wrong results.

Magneto-Dielectric Effects in Polyurethane Sponge Modified with Carbonyl Iron for Applications in Low-Cost Magnetic Sensors.

In this study, magnetizable polyurethane sponges (MSs) were obtained from commercial absorbent polyurethane sponges (PSs) doped with carbonyl iron microparticles (CIPs). Based on MSs, we manufactured cylindrical capacitors (CCs). The CCs were subjected to both a magnetic field and an alternating electric field, with a frequency of . Using an RLC bridge, we measured the series electric capacitance, , and the tangent of the loss angle, . From the functions and , we extracted the components of the complex dielectric permittivity. It was found that the CIPs embedded in the MS matrix aggregated, leading to magneto-dielectric effects such as the enhancement of the complex dielectric permittivity components when applying the magnetic field as a principal effect and the enhancement of the electric capacitance and time constant of the capacitors as a secondary effect. The obtained results represent landmarks in the realization of low-cost magnetic field sensors, deformation and mechanical stress transducers in the robotics industry, etc.

An Oil Multipollutant Detection Sensor With High Sensitivity and High Throughput

Oil is rich in information about the operating status of machinery and equipment, and oil condition monitoring is essential for maintaining the safety and reliability of machinery and equipment. Most sensors not only have the problem of small detection throughput and low detection efficiency, but also large-sized contaminants can easily block or even scratch the detection channel. A sensor with high sensitivity and high throughput for detecting multiple oil contamination is designed in this paper. The sensor comprises four glass capillary detection channels and four detection units, including a planar coil, solenoid coil, cylindrical parallel plate capacitor and rectangular parallel plate capacitor. Detection flux of the sensor is increased by 12 times its initial value, which significantly improves the detection efficiency. Through experimental research, in the inductance mode, the best excitation frequency is 2 MHz, and the voltage is 2 V. In the capacitance mode, the best excitation frequency is 1.8 MHz, and the voltage is 2 V. In addition, the sensor has a higher detection capability for Fe than Cu in the inductance mode, and a higher detection capability for water droplets than air bubbles in the capacitance mode. By analyzing the signal characteristics of each sensor unit, the sensor can distinguish between Fe of 38~900 μm and Cu of 88~900 μm, as well as water droplets greater than 130 μm and air bubbles greater than 100 μm. This research provides a new idea for online oil monitoring.

Bounding Formulae for Capacitance of Cylindrical Capacitor with Nonhomogeneous Dielectric Material

The paper deals with the capacitance of cylindrical capacitor which consists of nonhomogeneous dielectric materials. The infinite long cylindrical surfaces of capacitor have uniform distributed electric charges in axial direction, so that electrostatic boundary value problem which determines the electric field in the nonhomogeneous dielectric material is a twodimensional boundaryvalue problem. The derivation of the bounding formulae is based on the CauchySchwarz inequality. Examples illustrate the applications of the derived upper and lower bound formulae.

Thermographic Measurement of the Temperature of Reactive Power Compensation Capacitors

An excessive increase in reactive power consumption is unfavorable from the point of view of a power system. For this reason, devices compensating reactive power consumption are used. The capacitor is one such device. Capacitors must be tested regularly during their exploitation. One of the activities that should be performed is testing the degree of heating of the cells of a capacitor bank. Thermography can be used to perform such tests. This non-contact method has its limitations. Due to the angular emissivity and the change in the distance between the lens and the object under observation, the temperature measured with a thermographic camera may differ from the actual temperature. This phenomenon is visible on cylindrical capacitor cases. Consequently, depending on the location of the observation point on the capacitor case, the result of the thermographic temperature measurement may be different. To investigate this phenomenon, experimental work has been undertaken.

Ferroelectric Hafnium Zirconium Oxide Compatible With Back-End-of-Line Process

To scale the ferroelectric random access memory (FeRAM) technology toward 28 nm or beyond, it is critical to develop stacked capacitor (with sufficient surface area) to allow good sense margin for the 1-transistor- 1-capacitor (1T1C) bit cell. Therefore, to enable 3-D integration in back-end-of-line (BEOL) process, it is essential to optimize the fabrication recipes in low-thermal budget ( 50 s) in low temperature (\sim 350 °C), the ferroelectric properties of HZO could be fully manifested. No degradation is shown in the remnant polarization ( ${P}_{r}$ ) under the optimized low-temperature process. Furthermore, the retention/endurance characteristics with different ${P}_{r}$ states were measured to determine the minimally required write voltage. Finally, the SPICE simulation is conducted to evaluate the sense margin of the projected 28-nm 1T1C array with stacked cylindrical capacitors using the measured ${P}_{r}$ drift behavior over time.

Sensitivity of superconducting quantum interferometers to rotational motions

Based on the principle of equivalence of the general theory of relativity and the definition of the non-Euclidean metric of space in a non-inertial frame of reference associated with rotation, a geometric (topological) phase is found that occurs when traversing any closed loop. This approach made it possible to establish a deep physical analogy between various wave effects (both classical and quantum) in closed waveguides that arise under the conditions of their rotation. Due to the coherence of the wave function of spinless charge carriers (Cooper pairs of conduction electrons with oppositely directed spins) in superconductors in the ground quantum state (superconducting state), the appearance of a geometric phase in closed loops under rotation conditions can lead to interference effects in the presence of weak bonds in the loop. To register interference effects, it was proposed to use superconducting quantum interferometers placed in the electric field of a cylindrical or spherical capacitor. In accordance with the general theory of the geometric phase of rotation, the study obtained the basic relations between the geometric phase of rotation and the phase of the wave function induced by an external magnetic field, and an estimate of their values was obtained for acceptable values of the angular velocity of rotation, dimensions of superconducting quantum interferometers, and voltages on the capacitor. The errors in measuring the magnetic flux during the rotation of the measuring complex are determined. Taking into account the dependence of the magnitude of the geometric phase of rotation on the voltage across the capacitor and the size of the superconducting quantum interferometers, and also taking into account the specific range of angular velocities of rotation, the sensitivity of superconducting quantum interferometers to the angular velocity can be regulated by a rational choice of these parameters. Based on the results obtained, a new method for measuring magnetic fields was proposed using two superconducting quantum interferometers with different values of areas bounded by closed contours under conditions of rotational movements, which makes it possible to compensate for the disturbing influence of rotations on magnetic measurements, as well as to simultaneously determine the magnetic induction and angular velocity of rotation.

Parasitic Capacitance Analysis of Three-Independent-Gate Field-Effect Transistors

Three-Independent-Gate Field-Effect Transistors (TIGFETs) are a promising alternative technology that aims to replace or complement CMOS at advanced technology nodes. In this paper, we extracted the parasitic and intrinsic capacitances of a silicon-nanowire TIGFET device using three-dimensional numerical simulations in an attempt to accurately compare its capacitances and, consequently, circuit-level performances to CMOS at comparable nodes. Analytical models of the parasitic capacitances of a TIGFET transistor were derived using techniques such as the equivalent Schwarz-Christoffel transformation and standard cylindrical capacitors and show close agreement with numerical simulations. The maximum capacitance of a TIGFET transistor is $2\times $ larger than for a 15 nm CMOS High Performance (HP) device due to the TIGFET’s two additional gated contacts, but this is countered by its ability for multiple modes of operation which reduces the effective switching capacitance per device. A TIGFET transistor sees, on average, only a 30% increase in total capacitance compared to a CMOS HP device. Additionally, the TIGFET’s increased device functionality can be used to modify the circuit-level architecture of a TIGFET-based design to mitigate the performance impact of its larger device-level capacitance. This combination of a TIGFET’s (1) multiple modes of operation, and (2) circuit-level architecture lead to enhanced system performance. In particular, we show that at the 15 nm technology node TIGFET technology has 18% lower energy-delay product for a fan-out of 4 and higher when using 1-bit full-adder logic circuit than for the equivalent node CMOS HP.

Development of a model to estimate moisture contents based on physical properties and capacitance of seeds

The moisture content of seeds is an important factor that affects harvesting, storage, processing, and marketing. Estimating the moisture content of the seeds requires the development of a practical device. In this case, a cylindrical capacitor with an oscillator circuit was developed to measure the capacitance of the seeds. The samples were provided considering five types of seeds (capsular bean, corn, lentil, wheat, and rice). The moisture content levels of each type of seed were between 5% and 21% on a dry basis. An oscillator was built up using a NE555 chip, which estimated a capacitance by measuring a frequency. As an initial step in the modeling, the linear regressions between capacitance and moisture content were examined, in which the R2 values were greater than 0.98. Finally, based on the physical properties of each type of seed (porosity, density and dielectric constant) and capacitance, a model was developed to estimate the moisture content. The coefficient of determination (0.99) and accuracy (97%) indicate that the model for estimating the water content of the seeds has been successfully developed.