Characterization Of Electrical Properties Research Articles

Characterization of the Anisotropic Electrical Properties of Additively Manufactured Structures Made from Electrically Conductive Composites by Material Extrusion.

Additive manufacturing (AM) of components using material extrusion (MEX) offers the potential for the integration of functions through the use of multi-material design, such as sensors, actuators, energy storage, and electrical connections. However, there is a significant gap in the availability of electrical composite properties, which is essential for informed design of electrical functional structures in the product development process. This study addresses this gap by systematically evaluating the resistivity (DC, direct current) of 14 commercially available filaments as unprocessed filament feedstock, extruded fibers, and fabricated MEX-structures. The analysis of the MEX-structures considers the influence of anisotropic electrical properties induced by the selective material deposition inherent to MEX. The results demonstrate that composites containing fillers with a high aspect ratio, such as carbon nanotubes (CNT) and graphene, significantly enhance conductivity and improve the reproducibility of MEX structures. Notably, the extrusion of filaments into MEX structures generally leads to an increase in resistivity; however, composites with CNT or graphene exhibit less reduction in conductivity and lower variability compared to those containing only carbon black (CB) or graphite. These findings underscore the importance of filler selection and composition in optimizing the electrical performance of MEX structures.

Schottky Diode Leakage Current Fluctuations: Electrostatically Induced Flexoelectricity in Silicon.

Nearly four decades have passed since IBM scientists pioneered atomic force microscopy (AFM) by merging the principles of a scanning tunneling microscope with the features of a stylus profilometer. Today, electrical AFM modes are an indispensable asset within the semiconductor and nanotechnology industries, enabling the characterization and manipulation of electrical properties at the nanoscale. However, electrical AFM measurements suffer from reproducibility issues caused, for example, by surface contaminations, Joule heating, and hard-to-minimize tip drift and tilt. Using as experimental system nanoscale Schottky diodes assembled on oxide-free silicon crystals of precisely defined surface chemistry, it is revealed that voltage-dependent adhesion forces lead to significant rotation of the AFM platinum tip. The electrostatics-driven tip rotation causes a strain gradient on the silicon surface, which induces a flexoelectric reverse bias term. This directional flexoelectric internal-bias term adds to the external (instrumental) bias, causing both an increased diode leakage as well as a shift of the diode knee voltage to larger forward biases. These findings will aid the design and characterization of silicon-based devices, especially those that are deliberately operated under large strain or shear, such as in emerging energy harvesting technologies including Schottky-based triboelectric nanogenerators (TENGs).

Characterization of electrical and mechanical properties of Pandanus Atrocarpus flexible organic-based substrate for microwave communication in ISM applications

Characterization of electrical and mechanical properties of Pandanus Atrocarpus flexible organic-based substrate for microwave communication in ISM applications

AFM-sMIM Characterization of the Recombination-Enhancing Buffer Layer for Bipolar Degradation Free SiC MOSFETs

Due to the expansion of defects like single Shockley-type Stacking Faults inside the SiC epitaxial drift layer, during high current stress, classical SiC MOSFETs can be victims of the degradation of their electrical characteristics. The introduction of an epitaxial SiC buffer layer between the substrate and the n- drift epilayer, called recombination-enhancing buffer layer, was shown to avoid this degradation. In this paper, TCAD simulations of the electrical behavior of such a commercial SiC MOSFET device with varying buffer layer thickness are studied, indicating only small modifications of the electrical characteristics. These simulations are combined with the characterization of the local electrical properties using an AFM-sMIM technique, allowing to determine the real thickness of the different layers of the device. These measurements highlight an inhomogeneous conductivity in the SiC substrate, being probably compensated by the introduction of the SiC buffer layer.

Synthesis and characterization of structural, electrical, magnetic and microwave properties of Ba0.5Sr0.5Fe12O19-polyaniline nanocomposites

Synthesis and characterization of structural, electrical, magnetic and microwave properties of Ba0.5Sr0.5Fe12O19-polyaniline nanocomposites

Comprehensive characterization of structural, optical and electrical properties of CdS thin films annealed in air and vacuum

Comprehensive characterization of structural, optical and electrical properties of CdS thin films annealed in air and vacuum

Synthesis and characterization of structure, emission and electrical properties of MgxZn1−xO films obtained by spray pyrolysis with different Mg precursors

Synthesis and characterization of structure, emission and electrical properties of MgxZn1−xO films obtained by spray pyrolysis with different Mg precursors

Experimental and DFT investigations of Al-doped ZnO nanostructured thin films

Al doped ZnO thin films at different concentrations have been successfully synthesized, characterized experimentally, and investigated theoretically by density functional theory (DFT). The crystal structure analysis was carried out using X-ray diffraction (XRD) data. Wurtzite structures of a single phase with a preferred orientation along the (002) plane are obtained. The surface morphology has been investigated by atomic force microscopy (AFM) which showed homogeneous and compact surfaces with spherical shape grains that change to a wave like nematic structure with increasing Al doping rate. For a complete characterization, experimental and theoretical analysis of optical and electrical properties have been done using UV–Vis spectrophotometry, the four-probe method, electronic band structure and density of states calculations, and the Boltz-Trap code based on the semi classical theory of Boltzmann. Both, experimental and theoretical, studies indicate an increase in gap energy with high transparency in the visible region and electrical conductivity improvement due to a non-localized state around the Fermi level. The experimental and theoretical studies agree well and show a similar tendency of the results. Therefore, these properties of Al-doped ZnO open a new avenue for optoelectronic and photonic device applications.

In-situ rapid nondestructive characterization of multiple irregular three-dimensional grain boundary structures and electrical properties by nanorobot with SEM in ZnO

To address the problem of spatial quantification of irregular grain boundaries, a unique approach for the nondestructive characterization of multiple irregular three-dimensional grain boundaries is proposed using nanorobots with scanning electron microscopy (SEM) to accomplish in-situ rapid synchronized quantification of structures and electrical properties. By constructing a three-dimensional trigonometric geometric mapping relationship, multiple irregular three-dimensional grain boundary structures and electrical properties can be rapidly quantified. Experimental results demonstrate that it is feasible to accomplish in-situ rapid nondestructive characterizations. The two-dimensional profile shapes of the targeted grain boundaries at each layer exhibit irregular and non-uniform features in the Y-Z plane. The hypotenuse length between the virtual space tilting lines presents a three-dimensional characteristic in the X-Z plane. The spatial tilt angle of the virtual space tilting line can be calculated using the right-triangle relation. The unequal numbers of grains along the same tilted hypotenuse direction with equal lengths directly illustrate the existence of irregular and nonlinear grain boundaries in bulk ZnO ceramics. The relatively uniform spatial sizes of the grain boundary illustrate the coupled spatial characteristics existing in the irregular micro-structures. The relatively uniform equivalent circuit fitting parameters confirm the existence of relatively uniform doping components in bulk ZnO ceramics. Furthermore, this method provides a unique approach for the rapid nondestructive quantitative analysis of multiple three-dimensional irregular grain boundaries in bulk polycrystalline materials.

Characterization of electrical conductivity and dielectric properties of electroless NiP/rGO composite coated hemp fiber with various weight% of rGO and coating duration

The present study made an attempt to develop a conductive hemp fiber (HF) through an electroless Ni-P composite coating with reduced graphene oxide (rGO) as reinforcement. Four different Ni-P/rGO coated fibers were prepared with the variations in the coating time (20/40 min) and weight percentages of rGO (5/10 %). The coated fibers were characterized using various tools like: Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and field-emission scanning electron microscopy (FESEM), to identify the functional groups, phase structure, and morphological changes, induced by the rGO reinforcement. The coating duration and weight percentage of rGO had influenced the dielectric properties and electrical conductivity. In comparison, the coating duration of 40 min with 10 % addition of rGO has enhanced the electrical conductivity to 13.75 % and 37.5 % respectively. Furthermore, the mechanism behind the improvement in the conductivity is detailed in this study.

Enhanced electrical, optical and magnetic properties of BiFeO3 perovskite nanoparticles co-doped with Y and Cu

The present work includes the fabrication of pure BiFeO3 and Bi0.9Y0.1Fe1−xCuxO3 (x = 0.05, 0.10, 0.15) nanoparticles by the usual sol-gel route. The characterization of structural, morphological, optical, electrical, and magnetic properties of the synthesized samples was achieved through x-ray diffraction spectroscopy, Raman spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, an impedance analyzer, and a vibrating sample magnetometer. The Fourier transform infrared study confirmed the presence of Bi–O and Fe–O bonds. The x-ray diffraction patterns confirmed the rhombohedral (R3c) structure as a major phase with the orthorhombic (Pnma) structure as a secondary phase in all samples, and few amount of impurity phase of Bi25FeO40 was also determined. The surface morphology analysis showed the variation of particle size from 63 to 174 nm. The Raman spectra of 13 optical phonon modes, including 4A1 and 9E symmetric phonons, are observed for all samples, and the positions of these modes are almost similar, except the intensities of A1 modes. The optical measurements show a reduction in bandgap from 2.17 to 2.03 eV with co-doping, revealing itself as a more promising applicant in photovoltaics. An enhanced value of the dielectric constant is observed for different doped samples at different frequency regions from 100 Hz to 10 MHz. Magnetic investigation demonstrates the improved ferromagnetism with co-doping of Y and Cu due to distortion in the FeO6 octahedron. A maximum saturation magnetization of 0.26 emu/gm and a coercivity of 2915 Oe were found for Y concentration of 10% and Cu concentration of 15%.

Pulsed ultrasound assisted extraction of alternative plant protein from sugar maple leaves: Characterization of physical, structural, thermal, electrical, and techno-functional properties

Plant proteins are gaining in popularity and are increasingly being considered as an alternative to animal protein, thus a sustainable, yet comparable source of plant protein is highly recommended. To this end, the current study was conducted to investigate the structural, thermal, physical, and functional attributes, as well as the volatile profile of sugar maple leaves (SML) protein. To this end, SML protein was extracted by homogenization (10000 rpm, 5 min) pretreated ultrasound-assisted extraction (120000 J, 60% amplitude, 5:5 pulse, 25 °C, and 15 min) at varying pH (8−10) and compared with conventionally extracted SML protein. Among the different protein extracts, sonicated extract (pH9) provided a good protein yield (up to 7%) having higher protein content (210 mg Bovine serum albumin/g dry matter), thermal stability (onset of denaturation temperature:114 °C), and functional properties (solubility, emulsion capacity, water holding capacity, and antioxidant activity). On contrary, the characteristic green aroma, caused by 3-hexen-1-ol and nonanal, was found higher in sonicated protein extracts than that of macerated extracts. Having said that, this study showed the versatile properties of SML protein fractions that can be used as plant-based food ingredients.

Three-dimensional inertial focusing based impedance cytometer enabling high-accuracy characterization of electrical properties of tumor cells.

The differences in the cross-sectional positions of cells in the detection area have a severe negative impact on achieving accurate characterization of the impedance spectra of cells. Herein, we proposed a three-dimensional (3D) inertial focusing based impedance cytometer integrating sheath fluid compression and inertial focusing for the high-accuracy electrical characterization and identification of tumor cells. First, we studied the effects of the particle initial position and the sheath fluid compression on particle focusing. Then, the relationship of the particle height and the signal-to-noise ratio (SNR) of the impedance signal was explored. The results showed that efficient single-line focusing of 7-20 μm particles close to the electrodes was achieved and impedance signals with a high SNR and a low coefficient of variation (CV) were obtained. Finally, the electrical properties of three types of tumor cells (A549, MDA-MB-231, and UM-UC-3 cells) were accurately characterized. Machine learning algorithms were implemented to accurately identify tumor cells based on the amplitude and phase opacities at multiple frequencies. Compared with traditional two-dimensional (2D) inertial focusing, the identification accuracy of A549, MDA-MB-231, and UM-UC-3 cells using our 3D inertial focusing increased by 57.5%, 36.4% and 36.6%, respectively. The impedance cytometer enables the detection of cells with a wide size range without causing clogging and obtains high SNR signals, improving applicability to different complex biological samples and cell identification accuracy.

Synthesis, morphology and electrical property characteristics of MXene based titanium carbide (Ti3C2Tx) coating on non-woven cotton paper

In the present study, Ti3C2Tx type MXene was prepared by selective etching of Al from Ti3AlC2 with mesh size of 200. The powder form of raw material was used to fabricate Ti3C2Tx by in-situ HF etching method. The MXene is further coated on non-woven paper by simply dip coating method. The detailed structural, morphology and elemental content study of as prepared Ti3C2Tx MXene have demonstrated. The MXene (Ti3AlC2) powders show compact, layered morphology as expected for bulk layered ternary carbide. The detailed elemental analysis has carried out for Titanium carbide based MXene coated and uncoated woven paper. The lower conducting property obtained for paper coating due less amount of coating in the surface of paper instead of coating on glass substrate. The electrical property characterization of MXene coated non-woven paper and glass substrate have also been studied. Hence, the conductive coating of MXene-in water formulation achieved through simple dip coating methods is promising for low cost sensor, wearable shielding device fabrication towards renewable energy and healthcare applications.

Using multilayer structures to enhance the electrical properties of porous silicon for thermal sensing

Porous silicon holds great promise as an optically and electrically tuneable material platform for high performance thermo-resistive sensing. Fulfilling this promise requires the ability to independently control the two critical parameters which determine the sensitivity (specifically the minimum temperature difference resolution) of thermal detectors: the temperature coefficient of resistance (TCR) and 1/f noise of the sensing material. In single porosity films these two properties are monolithically dependent, with both TCR and 1/f noise constant increasing with porosity. Here we show that use of multilayer films allows manipulation of properties of the overall structure to simultaneously achieve high TCR and low 1/f noise. Characterization of electrical properties of various porosity combinations revealed that using a two-layer heterostructure on Si substrate with low porosity (48 %) as the top layer and a high porosity (80 %) as the lower layer, both high TCR (∼ 4.4 %/K) and low 1/f noise constant (4 × 10−13) could be simultaneously achieved. This transforms the ability to exploit porous silicon for future high sensitivity based thermal detectors.

Correction to: Structural and electrical property characterization of thermoelectric (Ca3Co4O9+δ) ceramic oxide fabrication by various reducing agent method

Correction to: Structural and electrical property characterization of thermoelectric (Ca3Co4O9+δ) ceramic oxide fabrication by various reducing agent method

Synthesis and characterization of structural, magnetic and electrical properties of Mn substituted Co-Zn ferrite

Spinel – type Zn0.5Co0.5 - xMnxFe2O3 ferrites were synthesized via solid-state reaction method with x values of 0.0, 0.1, 0.2, 0.3, and 0.4. X-ray diffraction was used to identify the crystallographic structure, which revealed the formation of a single-phase cubic spinel structure. The lattice parameter of Co-Zn ferrite samples was measured with a maximum value of 8.76 Å, and the density decreased with increasing concentration. The average grain size decreased with increasing Mn concentration. The Vibrating sample magnetometry (VSM) technique confirmed the soft ferromagnetic character of the entire sample, with a maximum magnetic saturation value of 73.67 emu/g, which was decreased with increasing Mn concentration. The magnetic coercivity (Oe) value led to a slightly hard magnetic phase with increasing Mn concentration, with a maximum value of 6.22. AC resistivity and permeability decreased with increasing frequency but were more activated at lower frequency, which is typical for ferrite behavior. The resistivity and dielectric constant correlated with the value of porosity and bulk density with increasing Mn percentage.

Cellular excitability and ns-pulsed electric fields: Potential involvement of lipid oxidation in the action potential activation

Recent studies showed that nanosecond pulsed electric fields (nsPEFs) can activate voltage-gated ion channels (VGICs) and trigger action potentials (APs) in excitable cells. Under physiological conditions, VGICs’ activation takes place on time scales of the order 10–100 µs. These time scales are considerably longer than the applied pulse duration, thus activation of VGICs by nsPEFs remains puzzling and there is no clear consensus on the mechanisms involved. Here we propose that changes in local electrical properties of the cell membrane due to lipid oxidation might be implicated in AP activation. We first use MD simulations of model lipid bilayers with increasing concentration of primary and secondary lipid oxidation products and demonstrate that oxidation not only increases the bilayer conductance, but also the bilayer capacitance. Equipped with MD-based characterization of electrical properties of oxidized bilayers, we then resort to AP modelling at the cell level with Hodgkin-Huxley-type models. We confirm that a local change in membrane properties, particularly the increase in membrane conductance, due to formation of oxidized membrane lesions can be high enough to trigger an AP, even when no external stimulus is applied. However, excessive accumulation of oxidized lesions (or other conductive defects) can lead to altered cell excitability.

Advance of microfluidic flow cytometry enabling high-throughput characterization of single-cell electrical and structural properties.

This paper reported a micro flow cytometer capable of high-throughput characterization of single-cell electrical and structural features based on constrictional microchannels and deep neural networks. When single cells traveled through microchannels with constricted cross-sectional areas, they effectively blocked concentrated electric field lines, producing large impedance variations. Meanwhile, the traveling cells were confined within the cross-sectional areas of the constrictional microchannels, enabling the capture of high-quality images without losing focuses. Then single-cell features from impedance profiles and optical images were extracted from customized recurrent and convolution networks (RNN and CNN), which were further fused for cell-type classification based on support vector machines (SVM). As a demonstration, two leukemia cell lines (e.g., HL60 vs. Jurkat) were analyzed, producing high-classification accuracies of 99.3% based on electrical features extracted from Long Short-Term Memory (LSTM) of RNN, 96.7% based on structural features extracted from Resnet18 of CNN and 100.0% based on combined features enabled by SVM. The microfluidic flow cytometry developed in this study may provide a new perspective for the field of single-cell analysis.

The Effect of Heat Treatment on Crystalline, Electrical and Optical Properties of ZnO/PVA Nanocomposites

ZnO/PVA nanocomposites have been successfully synthesized using the spin coating method by using synthesized ZnO, ZnO nanoparticles as filler, and PVA as a matrix. The synthesized films were treated at temperatures of 70, 90, and 120 °C. Some characterizations, such as I-V, UV-Vis, XRD, and SEM, have been carried out to study the electrical, crystalline, and optical properties of ZnO/PVA nanocomposites. The characterization of electrical properties using I-V measurements showed that ZnOsynthesized/PVA had a high current value of 1.55 nA, while ZnOnano/PVA had a smaller current value of 1.49 nA when treated at 120 °C. In addition, the higher the treatment temperature, the greater the resistance of ZnOsynthesized/PVA and ZnOnano/PVA. UV-Vis characterization showed that ZnOnano/PVA experienced a red shift when the temperature increased, while ZnOsynthesized/PVA and ZnOnano/PVA when treated at 120 °C experienced a blue shift. XRD characterization of ZnOnano/PVA showed that the higher the given temperature, the lower the crystallinity, from 45.77 to 34.81%. SEM characterization showed that ZnOnano/PVA at room temperature agglomerated and formed larger particles.