Electrical Characteristics Research Articles

Rapid and Cost-Effective Fabrication and Performance Evaluation of Force-Sensing Resistor Sensors

In this study, we developed a cost-effective and rapid method for fabricating force-sensing resistor (FSR) sensors as an alternative to commercial force sensors. Our aim was to achieve performance characteristics comparable to existing commercial products while significantly reducing costs and fabrication time. We analyzed the material composition of two widely used commercial force sensors: Interlink FSR-402 and Flexiforce A201-1. Based on this analysis, we selected 4B and 9B pencils, which contain high concentrations of graphite, and silicone sealant to replicate these material properties. The fabrication process involved creating piezoresistive sheets by shading A4 copy paper with 4B and 9B pencils to form a uniform layer of graphite. Additionally, we prepared a mixture of 9B pencil lead powder and silicone sealant, ensuring a consistent application on the paper substrate. Measurement results indicated that the force sensor fabricated using a mixture of 9B pencil powder and silicone sealant exhibited electrical and mechanical characteristics closely resembling those of commercial sensors. Load tests revealed that the hand-made sensors provided a proportional voltage output in response to increasing and decreasing loads, similar to commercial FSR sensors. These results suggest that our fabrication method can produce reliable and accurate FSR sensors suitable for various applications, including wearable technology, robotics, and force-sensing interfaces. Overall, this study demonstrates the potential for creating cost-effective and high-performance FSR sensors using readily available materials and simple fabrication techniques.

Enhancement in power factor through rare-earth samarium doping in Cu2SnSe3 system

Cu2SnSe3 has drawn enough attention as a potential thermoelectric material due to its unique electronic and thermal properties. We present the impact of Sm doping on the Cu2SnSe3 system’s Sn site. The polycrystalline samples of Cu2Sn1-x Sm x Se3 (0 ≤ x ≤ 0.08) were prepared using the solid-state reaction technique followed by conventional sintering. The crystal structure was characterized using XRD and the results reveal that the samples have a diamond cubic structure with a space group of F4̄3m. Scanning Electron Microscopy (SEM) analysis indicates a uniform surface homogeneity within the sample. Furthermore, the introduction of Sm causes a reduction in porosity. The electrical transport characteristics were studied in the mid temperature range of 300–650 K. The Seebeck coefficient of all the samples were found to be positive within the temperature range under study, suggesting that holes constitute the majority charge carriers. This is also confirmed by the Hall measurements as the carrier concentration was positive for all the samples. The inclusion of Sm has led to a reduction of electrical resistivity and Seebeck coefficient and hence power factor of ~539 μW mK−2 for x = 0.08 at 630 K which is ten times greater as compared to x = 0 whose power factor is ~56 μW mK−2 at 630 K is achieved which makes it suitable for thermoelectric applications.

Unravelling NbSe2 single crystal: First principle insights, optical properties, synthesis and X-ray diffraction profile investigation

Niobium diselenide (NbSe2) crystals were synthesized using the chemical vapour transport (CVT) technique. The Generalized Gradient Approximation (GGA) method was used in the density functional theory (DFT) calculation. The Perdew-Burke-Ernzerhof (PBE) pseudopotential function was utilised to emphasise the structural, electrical, elastic constant, and optical characteristics of the hexagonal P63/mmc symmetric structured crystalline phase of NbSe2. Additionally, the density of states (DOS) revealed that, at the Fermi level, the Nb (3d) states predominated, with the Se (5p) and Se (5 s) states playing a minor role. The band structure confirmed the crystal's metallic nature, which showed an overlap between the conduction and valence bands. Scherrer method, Williamson-Hall (WH) analysis, Size-Strain Plot (SSP), and Halder-Wagner (HW) plot utilising uniform deformation model (UDM), uniform stress deformation model (USDM), and uniform deformation energy density model (UDEDM) models were used to investigate the X-ray diffraction (XRD) profile. The crystallite size, inherent stress, strain, and energy density parameters were estimated. Optical microscopy and transmission electron microscopy (TEM) had both been used to study surface morphology.

Relationship between the induced voltage of a rotor bar and the rotation characteristics of a high-temperature superconducting induction motor

Although high-temperature superconducting induction motors have a simple structure, they are distinguished by their high efficiency and high power density. However, an accurate theoretical model that defines the primary electrical characteristics controlling the motor has not been established because of the nonlinear characteristics of high-temperature superconducting squirrel-cage rotor winding. As part of establishing such a model, an experiment was conducted to analyze the relationship between the induced voltage of the rotor bar in a high-temperature superconducting squirrel-cage rotor winding and stator-side quantities (voltage and transport current), as well as its rotation characteristics. A subject was a 1.5 kW class induction motor using Bi–Sr–Ca–Cu–O high-temperature superconducting rotor bars and the experiment was performed at a temperature and a frequency of 77 K and 60 Hz, respectively. The induced voltages of the rotor bars were measured by applying a rotating magnetic field and exhibited a distorted waveform characterized by a third-order harmonic in a magnetic flux flow state. Despite the distorted voltage waveform of the rotor bar, the stator transport current responsible for driving the induction motor remained unaffected and the motor initiated rotation in a slip rotation mode. From the above results, it was experimentally clarified that a stator voltage exceeding the critical current of the rotor bar must be applied when starting the induction motor. It was also shown that the rotor bar can be regarded as a constant resistance for a constant effective value of the stator current when transitioning the motor into a slip rotation state.

Analog and Digital Resistive Switching in W/TiO2/ITO Devices: The Impact of Crystallinity and Indium Diffusion

Abstract The resistance-switching memristor with capabilities of information storage and brain-inspired computing has prime importance in recent research. In this study, the impact of crystallinity and Indium diffusion on the existence of analog and digital resistive switching in a W/TiO2/ITO device has been reported. The memristor devices are fabricated by depositing titania films by sol-gel and spin-coating techniques. The films annealed at 250 ℃ and 400 ℃ were characterized using X-ray diffraction, Raman spectroscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy (XPS). The characteristic anatase phase started appearing after annealing at 400 ℃, whereas the 250 ℃ annealed sample was in the amorphous state. The electrical characterization revealed significant differences in the switching characteristics of amorphous and crystalline samples, especially in the switching interface, compliance properties, and current conduction mechanism. The grain boundary assisted oxygen vacancy migration, and the diffusion of indium ions from the ITO substrate helped the crystalline sample to show highly stable and reproducible resistive switching compared to amorphous film. The XPS studies confirmed the indium ion diffusion in the crystalline sample. The oxygen vacancy-induced barrier modulation and conductive filament formation caused characteristic switching in amorphous and crystalline samples, respectively. Schottky emission in the amorphous film and SCLC mechanism in the crystalline film confirmed the experimental results. This study provides a distinctive viewpoint and an innovative strategy for developing multifunctional resistive switching devices.

The effect of temperature on the electrical characteristics of zigzag and armchair black phosphorus based 2D MOSFET

Abstract A first time comparative study of the thermal dependence of vital electrical characteristics of 2D MOSFETs based on black phosphorus for both zigzag and armchair orientations is presented in this paper. It is seen that a higher in-plane thermal conductivity in zigzag direction results in a much better on state current performance which comes at the cost of orders of magnitude increase in gate leakage and a reduced on to off state current ratio. The effect of temperature on threshold voltage (VTH), short channel effects like drain induced barrier lowering (DIBL), subthreshold swing (SS), Schottky barrier height ΦSB and transconductance behavior in both zigzag and armchair orientations is thoroughly discussed and the inherent physical mechanisms resulting the variations are also presented. Though increase in temperature is found to deteriorate the SS and drain conductance but at the same time, it is found to improve the short channel performance of the devices under consideration.

Comprehensive analysis of the performance of a microfluidic photoelectrochemical solar cell with heat exchanger

A dye-sensitized solar cell (DSSC) is a type of photoelectrochemical cell that converts sunlight directly into electricity using a photoanode with a dye-sensitized, nonporous semiconductor layer. This study investigates the impact of integrating microfluidic capabilities into DSSCs, resulting in a flow-cell configuration that introduces new electrical characteristics without compromising its performance. The primary goal of the work was to define and determine the values of heat, mass, and charge transport resistances, and to explore their relationships with the cell’s current–voltage characteristics, temperature, light intensity, and spectra. We employed both experimental methods and computational fluid dynamics using the Lattice-Boltzmann solver to analyze the cell’s dynamics. A novel multilayered microfluidic DSSC (µDSSC) was designed, featuring an innovative “gapless” configuration with a photoactive surface area exceeding 7 cm2, integrated directly with a microfluidic heat exchanger. This configuration allowed the µDSSC to achieve a power conversion efficiency (PCE) of at least 6 % under standard test conditions, with a fill factor reaching up to 68 %. By gradually covering the cell surface, the impact of series resistance (Rs) on PCE was minimized, enabling a maximum PCE of 19–22 %. A new integral definition of the fill factor (IFF) was proposed, which accurately describes the performance of cells constrained by ion mass transport resistance. For the gapless µDSSC, the IFF ranged from 58 % to 88 %. Additionally, we introduced a maximum cell efficiency (MCE) parameter to represent the cell’s efficiency at the theoretical limit of Rs = 0, determined to be 20.7 % for the gapless µDSSC. This MCE value is specific to the cell and is independent of the illuminated surface area and incident light intensity. The thermal efficiency of µDSSC cells is generally limited by heat conduction through the multilayer structure, but at practical cell surface temperatures of 50–80 °C, this limitation is 3 to 6 times less significant than the limitation imposed by the maximum solar energy flux reaching the cell surface. The integration of microchannels into the cell led to a 58 % reduction in hydraulic resistance along the main flow direction. While electrolyte flow typically reduces efficiency in wide-gap DSSCs, the gapless configuration minimizes mass transport resistance, ensuring that fluid flow does not adversely affect the performance of gapless µDSSCs.

Experimental and theoretical study of two Salen-type Schiff bases: green synthesis, characterization, corrosion inhibition efficiency, and biological activity

As eco-friendly corrosion inhibitors, antioxidants, and antibacterial agents, this study assesses 1,3-bis(2-hydroxybenzylidene) thiourea (B1) and 1,3-bis(2-hydroxybenzylidene) urea (B2), two new Schiff bases, on their performance in these areas. We successfully synthesized these Schiff bases in just 15 minutes using an environmentally friendly approach, and the yield was rather good, ranging from 69.8% to 87.53%. When compared to B2, B1 showed more effective corrosion inhibition and better antioxidant activity. Both chemicals were highly effective against microbes, while B1 was particularly effective against Aspergillus. B. We measured the weight loss to examine the corrosion inhibition impact of XC48 carbon steel in 1M HCl. The findings revealed that at the ideal concentration of 5.10–4 M, the estimated IE% of the Schiff bases was 63.8% for B2 and 87.28% for B1. This study employed the Langmuir isotherm model to determine a number of thermodynamic and kinetic characteristics, all of which pointed to a physical adsorbed state. Promising electrical characteristics and robust adsorption on metal surfaces for B1 were corroborated by theoretical investigations employing density functional theory (DFT) and molecular dynamics (MD) simulations. Both the theoretical and practical aspects align with one another.

Effects of NiO Doping and Trench Wall Tilt on Ga2O3 PiN Diodes Performance

Gallium Oxide (Ga2O3) is a promising material for next-generation power semiconductors due to its wide bandgap (∼4.9 eV), high Baliga’s figure of merit (FOM) (3444 W/cmK), and high breakdown field (Ec, 8 MV/cm). To achieve high blocking and low leakage current, research has been conducted on PN heterojunctions and bevel structures. In this paper, we performed simulations using Sentaurus TCAD to investigate the impact of NiO doping concentration and NiO’s trench tilt angle on the electrical characteristics of NiO/Ga2O3 PiN diodes with trench NiO. As the NiO doping concentration increased, the resistance decreased from 21.5 to 7.5 mΩcm2, and we observed the expansion of depletion from NiO to the NiO/Ga2O3 interface. Furthermore, we confirmed a reduction in resistance and a change in breakdown voltage with an increase in NiO trench tilt. By understanding the optimal angle to mitigate the concentration of high electric fields in the edge region, we anticipate the fabrication of stable Ga2O3 PiN diodes.

Development of a Miniaturized 2-Joule Pulsed Plasma Source Based on Plasma Focus Technology: Applications in Extreme Condition Materials and Nanosatellite Orientation

Plasma focus devices represent a class of hot and dense plasma sources that serve a dual role in fundamental plasma research and practical applications. These devices allow the observation of various phenomena, including the z-pinch effect, nuclear fusion reactions, plasma filaments, bursts, shocks, jets, X-rays, neutron pulses, ions, and electron beams. In recent years, considerable efforts have been directed toward miniaturizing plasma focus devices, driven by the pursuit of both basic studies and technological advancements. In this paper, we present the design and construction of a compact, portable pulsed plasma source based on plasma focus technology, operating at the ~2–4 Joule energy range for versatile applications (PF-2J: 120 nF capacitance, 6–9 kV charging voltage, 40 nH inductance, 2.16–4.86 J stored energy, and 10–15 kA maximum current at short circuit). The components of the device, including capacitors, spark gaps, discharge chambers, and power supplies, are transportable within hand luggage. The electrical characteristics of the discharge were thoroughly characterized using voltage and current derivative monitoring techniques. A peak current of 15 kiloamperes was achieved within 110 nanoseconds in a short-circuit configuration at a 9 kV charging voltage. Plasma dynamics were captured through optical refractive diagnostics employing a pulsed Nd-YAG laser with a 170-picosecond pulse duration. Clear evidence of the z-pinch effect was observed during discharges in a deuterium atmosphere at 4 millibars and 6 kilovolts. The measured pinch length and radius were approximately 0.8 mm and less than 100 μm, respectively. Additionally, we explore the potential applications of this compact pulsed plasma source. These include its use as a plasma shock irradiation device for analyzing materials intended for the first wall of nuclear fusion reactors, its capability in material film deposition, and its utility as an educational tool in experimental plasma physics. We also show its potential as a pulsed plasma thruster for nanosatellites, showcasing the advantages of miniaturized plasma focus technology.

Unveiling the structural and electrical features of Al/p-CZTS thin film schottky structure for photovoltaic application: a comparative parameter extraction study

Unveiling the structural and electrical features of Al/p-CZTS thin film schottky structure for photovoltaic application: a comparative parameter extraction study

A Perspective on the Identity of the Acupoint.

Recently, several previously undiscussed concerns in acupuncture research have been brought to light. Among these, the core issue stems from the ambiguity surrounding the identity of acupoints. Hence, the question "What is the identity of acupoints?" remains of particular importance in acupuncture research. To answer this question, we reviewed the original concept of acupoints explained in Oriental medicine, from which acupuncture treatment originated, and examined scientific research on acupuncture and acupoints. We then proposed a perspective on the identity of acupoints and speculated about a possible reason for their elusive nature: qi, which congregates at and flows in and out of acupoints, might be bioelectricity, making these points inherently difficult to measure anatomically or histologically. Consequently, acupoints are suggested to be spaces where bioelectricity congregates, thus inevitably exhibiting electrical characteristics.

Comparison of the effect of different external electrodes on discharge plasma-assisted diffusion flame stabilization

To optimize the design of plasma injectors, the influence of different external electrodes on plasma-assisted flame stabilization was assessed by using a nonequilibrium plasma injector flame control setup. The electrical characteristics of the injector, flame structure parameters, flame intensity, discharge power, and cost-to-effectiveness ratio under different external electrodes (four mesh electrodes and one copper foil electrode) were analyzed using electrical and optical methods. The results show that reducing the mesh size of the external electrode leads to a decrease in breakdown voltage. Compared with a ceramic dielectric barrier-based injector, an injector with a quartz dielectric barrier produces a higher breakdown voltage under the same conditions. For the same actuation voltage, the discharge current increases as the mesh size of the external electrode decreases, and combustion is enhanced by the discharge plasma; therefore, it is better to adopt a smaller mesh hole size to realize good flame stabilization under a lower actuation voltage. However, under the studied working conditions, reducing the mesh hole size of the external electrode increases the cost-to-effectiveness ratio of plasma injector-based flame stabilization. Thus, considering the cost-to-effectiveness ratio and the weight of the injector, an external electrode with a larger mesh hole size should be chosen, which contradicts the above rule.

OFETs Electric Characteristics with different Organic Material for Low Power Flexible Electronics Design

OFETs Electric Characteristics with different Organic Material for Low Power Flexible Electronics Design

Effect of doping of metal salts on polymers and their applications in various fields

Abstract Transition metal compounds (TMCs) provide the benefits of vast reserves, affordability, non-toxicity, and environmental friendliness, making them highly sought-after in recent times. Integrating transition metal salts into polymers may result in substantial enhancements in optical and electrical characteristics, making them appealing for many applications. Transition metal ions may display a range of electronic transitions, which enables the adjustment of absorption and emission spectra. This characteristic has significant value in applications such as light-emitting devices (LEDs) and sensors. The photoluminescence of polymers may be improved by the addition of transition metal salts, which results in light emission that is both more brilliant and more efficient. On the other hand, this is advantageous for screens and optoelectronic devices. The presence of transition metal salts in polymers may help to improve their optical stability, hence lowering the probability that the polymers will degrade or change color over time. When it comes to the performance of optical devices over the long run, this is quite essential. Elevating the electrical conductivity of polymers is possible via the use of transition metal salts. This is very helpful in the process of developing conductive polymers for use in applications such as electronic fabrics, organic solar cells, and flexible electronic devices. Transition metal salts can affect the electrical band structure of polymers, which enables the band gap of the material to be tuned. This is very necessary in order to maximize the amount of light that is absorbed by photovoltaic devices. Through having all these benefits, we conducted a review to find out the effects on polymeric materials.

Simulation of synaptic properties of ferroelectric memory capacitors and neural network applications

In this work, the electrical properties and synaptic characteristics of hafnium oxide-based ferroelectric memory capacitor with metal - ferroelectric layer - metal (MFM) structure were simulated using TCAD (technology computer aided design) software. Based on the synaptic potentiation/depression characteristics of the simulated memory capacitor, a multilayer perceptron (MLP) network was constructed, and the recognition accuracy and convergence speed of the MLP network in the MNIST recognition task were simulated, and the feasibility of the ferroelectric memory capacitor synaptic device for real neural network operation was analyzed. The results show that the recognition accuracy of the MLP network reaches 93% and stabilizes after 50 iterations of training, and the recognition accuracy of the MLP network is already at a high usable level after a smaller number of training times of 20, which suggests that the synaptic plasticity of the ferroelectric memory capacitor has a good potential for the practical application of the weight updating of the MLP network.

Artificial optoelectronic synapse based on CdSe nanobelt photosensitized MoS2 transistor with long retention time for neuromorphic application

Abstract Optoelectronic synaptic devices have been regarded as the key component in constructing neuromorphic computing systems. However, the optoelectronic synapses based on conventional 2D transistor are still suffering low photosensitivity and volatile retention behavior, which can affect the recognition accuracy and long-term memory. Here, a novel optoelectronic synaptic device based on surface-state-rich CdSe nanobelt photosensitized 2D MoS2 transistor is demonstrated. Benefiting from the excellent light absorption of CdSe and effective charge trapping at the hetero-interface, the device exhibits not only high photosensitivity but also long retention time (>1,500 s). In addition, typical synaptic functions including the excitatory postsynaptic current, paired-pulse facilitation, the transformation from short-term to long-term plasticity, the transformation from short-term to long-term plasticity, spike-amplitude-dependent plasticity, and learning-forgetting-relearning process are successfully simulated and modulated by light stimulation. Most importantly, an artificial neural network is simulated based on the optical potentiation and electrical habituation characteristics of the synaptic devices, with recognition accuracy rates of 89.2, 93.8, and 91.9 % for file type datasets, small digits, and large digits are achieved. This study demonstrates a simple and efficient way to fabricate highly photosensitive optoelectronic synapse for artificial neural networks by combining the merits of specific materials and device architecture.

Enhancing Polylactic Acid Properties with Graphene Nanoplatelets and Carbon Black Nanoparticles: A Study of the Electrical and Mechanical Characterization of 3D-Printed and Injection-Molded Samples

Enhancing Polylactic Acid Properties with Graphene Nanoplatelets and Carbon Black Nanoparticles: A Study of the Electrical and Mechanical Characterization of 3D-Printed and Injection-Molded Samples

Effect of Gaussian defect density variations on electrical characteristics of TIPS-pentacene-based OTFT

Effect of Gaussian defect density variations on electrical characteristics of TIPS-pentacene-based OTFT

Fabrication of Al/n-GaN/p-Si/Al diodes by thermal evaporation and evaluation of effect of gamma irradiation on device properties

This study investigates the impact of γ-irradiation on the material and device properties of Al/n-GaN/p-Si/Al heterojunction diodes. GaN thin films were deposited on glass and p-Si substrates using thermal evaporation, followed by annealing at 450 °C. The diodes were subjected to γ-irradiation doses of 0, 3, and 6 kGy. X-ray diffraction (XRD) measurements revealed significant structural changes, including phase transitions influenced by radiation. Electrical characteristics were assessed through current–voltage (I-V) measurements within the ± 2 V range. Notably, the ideality factor for the annealed diodes improved from 6.60 to 4.62 and 3.85 with increased γ-irradiation. The barrier height was determined to be 0.85 eV, and it did not exhibit a significant change upon γ-irradiation dose. The results provided valuable insights into the response of heterojunction diodes to radiation exposure, aiding in the understanding and potential improvement of the radiation resistance of GaN-based electronic devices.