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In this article, process of current flow in a nanowire radial p-i-n diode has been considered in detail. It has been shown that cylindrical geometry of the structure gives rise to specific asymmetry of the concentration distribution for current carriers injected to the i-layer, which is opposite to asymmetry that is due to inequality of carriers’ mobilities. This specific asymmetry rises with bringing the i-layer nearer to the nanowire center. Together with that, decrease of the current density in a “long” p-i-n diode and its increase in a “short” p-i-n diode take place (at given forward voltage). And variation of radial thickness of the i-layer demonstrates maximums in the current density at the thickness close to the bipolar diffusion length.

In this work, we analyzed the current-voltage characteristics in the temperature range of the hybrid organic material C24H24N6O3Zn in order to determine the prospects for using this compound as a semiconductor material. The range of temperature measurements was from 270 to 330 K. An electrochemical analysis of the studied coordination compound was carried out, the energies of the HOMO and LUMO levels were calculated. The method of obtaining, microscopy, and also the method of measuring the temperature dependences of the electrical properties of the obtained thin films of these hybrid materials based on zinc complexes are described. A number of fundamental values of the films of this coordination compound have been calculated: the activation energy is  0.88 eV and the mobility of charge carriers is  1.4710-11 cm V-1 s-1.

Photovoltaic modules are rated at standard test conditions, STC, but in real life operation they are exposed to very different conditions. The power of a module and its device parameters are obtained from the current-voltage characteristic (I-V curve) of the module but the curve varies with irradiance and temperature conditions. The I-V curve is transformed from real operational conditions to STC and vice versa with translation equations. In this paper we investigate the fundamental nature of the translation equations and show that they introduce consistent bias in the power and device parameters, obtained from the translated I-V curves. We show that the nature of the translation equations forces the device parameters to transform from one to another set of irradiance and temperature conditions by algebraic transformations, which are derived in this paper. Validation of our findings is given for the series resistance. Our findings have significant implications for the assessment of module degradation.

Bismuth telluride based photosensitive elements were obtained and their properties were studied. Liquid exfoliation was used for bismuth telluride 2D material suspensions preparation in organic solvent only with no additional surfactants. 2D sheets in suspension had average size of 200–300 nm and thickness of 2–2.5 nm. Resistive photosensitive elements were obtained by the drop-casting method. The photoresponses of sensitive elements studied at room temperature and liquid nitrogen temperature.

Degradation and partial shading impact the long-term reliability and power production of photovoltaic (PV) modules and power plants. Time-series power ( P mp ) and current–voltage (I-V) curve datastreams from PV modules enable a remote diagnostic approach to quantify active degradation mechanisms and identify partial shading. We study three to nine years of these datastreams, including 3.6 million I-V curves and 36 million P mp values, from eight PV modules, four each of double-glass and glass-backsheet module architectures, located in three distinctly different Koppen-Geiger climate zones, to determine the module’s performance loss rates (PLR), identify active degradation mechanisms and power loss modes, along with partial shading by local objects. Considering both module architectures, PLR results indicate that the BSh climate zone is the most aggressive for module degradation, while the Alpine ET zone is the mildest climate. PLR of double-glass modules located in BWh and BSh climate zones are different due to the significantly greater uniform current loss (ΔPIsc) for double-glass modules in BSh, at a 5% significance level. Power loss for four out of five modules located in the BWh and BSh climates are dominated by uniform current degradation. Statistical analysis of multistep I-V curves detects partial shading experienced by three studied modules with details of the shading profile, the shading Poynting vector diagram for the obstacle’s relative position, shading scenarios, and duration. This work demonstrates how remote monitoring and diagnosis of P mp & I-V time-series of modules can provide quantitative operations and maintenance insights into system performance, degradation mechanisms, and shading.

Perovskite solar cells are emerging photovoltaic devices with PCE of above 25%. Perovskite are suitable light absorber materials in solar cells with excellent properties like appropriate band gap energy, long carrier lifetime and diffusion length, and high extinction coefficient. Simulation study is an important technique to understand working mechanisms of perovskites solar cells. The study would help develop efficient, stable PSCs experimentally. In this study, modeling of perovskite solar cell was carried out through Setfos software. The optimization of different parameters of layer structure of solar cell would help to achieve maximum light absorption in the perovskite layer of solar cell. Simulation study is based drift-diffusion model to study the different parameters of perovskite solar cell. Hysteresis is one of the factors in the perovskite solar cell which may influence the device performance. The measurement of abnormal hysteresis can be done by current-voltage curve during backward scan during simulation study. In backward scan, the measurement starts from biasing voltage higher than open circuit voltage and sweep to voltage below zero. The numerical simulation used to study the various parameters like open circuit voltage, short circuit current, fill factor, power conversion efficiency and hysteresis. The simulation results would help to understand the photophysics of solar cell physics which would help to fabricate highly efficient and stable perovskite solar cells experimentally.

Present work illustrates synthesis of Cr doped WO3 nanostructures (NS) (2 wt. %, 4 wt. % and 6 wt. %) by co precipitation method using surfactants and reported enhanced impedance, capacitance-voltage and current-voltage (I-V) characteristics. NS were characterized by cyclic voltammetry (CV), scanning electron microscopy (SEM), X-ray diffraction (XRD), UV-Visible (UV-Vis) spectroscopy, pelletized samples performed I-V, C-V and impedance measurements. Impedance results reveal that the pelletized samples of highest doped Cr showed remarkable increase in admittance with respect to the biased voltage. I-V characteristics of highest doped Cr exhibited enhanced surface conductivity as compared with applied current. The output power considerably increases for the 6 wt. % of Cr doped WO3 and doping percentage of Cr increases surface conductivity, power output, admittance considerably enhances in the material matrix. This work demonstrated that Cr doped WO3 has more sensitivity towards I-V, C-V and impedance value considerably varies with the applied bias voltage. The limitation is not certain in case of doped nanomaterials of Cr-WO3, since these materials possesses nonlinear properties and can find applications in the diversified filed of nano electronics. The authors reported work can be a key guide for the upcoming researchers in the area of biomedical devices, nanoelectronics, sensors, wherein Cr-WO3 NS finds applications because of its enhanced I-V, C-V, Impedance characteristics. The work has been carried out to understand the electrical and electronic properties of doped nanomaterials in the original work place and analysis has been carried out at various institutions where the provisions for the experimentation is being made.

In this work, a new method for obtaining the current-voltage curve for crystalline silicon and thin-film flat panels is presented. It is based on the single-diode model, with a variable shunt resistance and series resistance. New expressions for the shunt resistance and open circuit voltage as a function of the temperature and irradiance are deduced. Besides, a procedure to translate the series resistance to arbitrary conditions is proposed. The diode ideality factor and shunt resistance are obtained by optimization. The rest of the parameters that appear in the current-voltage curve are obtained from the module measurements by means of theoretical expressions. The procedure for obtaining the current-voltage curve under arbitrary operating conditions is also described. The results obtained with the developed model are compared with experimental measurements in cadmium telluride and amorphous silicon modules, and with results published in the literature for other technologies. The model faithfully reproduces the experimental values. For all the modules, the root mean square error for the maximum power is lower than 2% (below 1.5% in most cases). These errors are lower than those reported in the literature for other models. In particular, the results are significantly more exact in the case of thin-film modules., Comunidad de Madrid

Field-effect graphene transistors (FGTs) based on single-layer graphene using the developed simplified combined self-consistent model are simulated. It is used to compare the results of calculating the current–voltage (I–V) characteristics of five devices with the same geometric parameters with different materials of the gate dielectric of the upper gate. The influence of the thickness of the dielectrics of the upper and lower gates on the transfer I–V characteristic of a dual-gate FGTs is analyzed

—An experimental stand has been created to assess the characteristics of the electromagnetic field under which the current–voltage (I–V) characteristic of semiconductor elements change. The developed stand was used for a series of experiments on the effect of signals with different parameters on a KD520A diode in order to record changes in the slope of the diode’s I–V characteristic as an onset degradation feature of the p–n-junction. This is done by recording the amplitudes of higher harmonics under the action of microwave signals.

The performance of solar cells influences the reliability, lifetime, cost, and safety of photovoltaic power plants. The electrical performance of these cells, as well as, their degradation rates over time, can vary between individual cells within the same photovoltaic module. Current–voltage measurements can provide detailed data on cell performance, however, it cannot be performed on individual cells in encapsulated modules. In this study, we propose a contactless and nondestructive method that is based on Suns-photoluminescence measurements to extract the current-voltage characteristics of individual solar cells under operating conditions in the field. Applications of the method to identify the extent of various degradation mechanisms, such as light-induced and potential-induced degradation, are demonstrated and discussed. The main advantages of the proposed method include its low cost, and its fast and easy applicability.

Exploring new materials and structures and optimizing integrated photosupercapacitors systems are extensively developed. In this work, we report the study of the influence of light intensity on the performance of photosupercapacitors. The photosupercapacitors was constructed from active materials TiO2-ZnO-natural dye-DSSC and BaTiO3 based supercapacitors. The photoelectric current and open current voltage at various light intensity. The photo-charging was measured under various light intensity illumination 30400, 60800, 91200, 144500, and 170,800 Lux. It is shown that intensity significantly influences the charging rate on the supercapacitor section. The higher the intensity, the quicker the charging occurs.

In this study, Schottky contacts have been fabricated on n-InP (1 0 0) using an Al/n-InP/In configuration. The current voltage (I-V) and capacitance voltage (C-V) characteristics of Al/n-InP/In Schottky diodes were calculated from the liquid nitrogen temperature to the room temperature by steps of 10 K before annealing of this structure and after annealing at 400 °C for 3 min. The series resistance, ideality factor and barrier height values calculated using I-V characteristics, Cheung functions, Norde (F-V) functions, and C-V characteristics before and after annealing the contact and compared for each temperature. These measurements clearly showed that the Al/n-InP/In Schottky diode became extremely stable due to the annealing process and the mean barrier height value have been increased from 0,494 to 0,674 eV after thermal annealing at 400 °C. In addition, temperature dependent barrier height values of as-fab. and annealed (at 400 °C) Al/n-InP/InSchottky contacts are consistent with “the barrier inhomogeneous model” of Schottky diodes.

In this work, p-CuO/n-Si hetero-junction contacts were produced by thermal evaporation technique and current-voltage (I-V) characteristics of the junctions were investigated at room temperature. It has been observed that the structures exhibit diode characteristics and diode parameters such as ideality factor, effective barrier height and series resistance were calculated from the forward bias I-V characteristics and Cheung Functions were used to check the consistency of the results. Norde's functions combined with the forward I-V method has been used to extract the parameters. The barrier height and series resistance values obtained from Norde's function have been compared with those from Cheung functions. It has been seen that there are a good agreement between the barrier height values from both method, but the series resistance values obtained from Norde's functions are considerably larger than those of Cheung functions. Also, photovoltaic characterization of the junctions was made from current density-voltage (J-V) characteristics under AM 1.5 illumination (100 mW.cm = 2). (c) 2021 Elsevier Ltd. Selection and peer-review under responsibility of the scientific committee of the International Congress on Semiconductor Materials and Devices, ICSMD2018.

In this study, we carried out the analysis of the influence of unconventional current-phase relation of Josephson junction with additional fractional term sin\phi/2 to first harmonic sin\phion current-voltage characteristics. The current-voltage characteristic of the junction was calculated for the different amplitudes of fractional term m and McCumber parameter . It was shown increasing the amplitude of fractional terms leads to increasing in the hysretesis on the current-voltage characteristics.

The current–voltage (I–V) characteristics of n-GaP–p-(InSb)1 – x(Sn2)x (0 ≤ x ≤ 0.05) heterostructures have been studied. At low voltages (V < 0.5 V), the I–V curve is described by the exponential law I = I0exp(qV/ckT), while at higher voltages (from 0.5 to 1.8 V) it obeys the power law I = AVm with various values of coefficient A and exponent m dependent on the voltage. At still higher voltages (from 2.10 to 2.48 V), the characteristic exhibits a sublinear behavior described by the equation V = V0exp(Jd/2kTμpNt).

As a fundamental unit of molecule-based electronics, a molecular rectifier is one of the most widely studied molecular devices, of which the ideal current–voltage (I–V) characteristics based on a t...

In this paper, the detail study of electrical conductivity of single layer graphene (SLG) on silicon dioxide (SiO2)/Silicon substrate irradiated by high energy (MeV) electron is presented. The SLG samples prepared by Chemical Vapor Deposition (CVD) were irradiated by 50 kGy, 100 kGy and 200 kGy doses of electron radiation at energy voltage of 3 MeV. Current-Voltage (I-V) characteristics and conductivity of the pristine and irradiated graphene samples were measured and analysed using I-V measurement at room temperature. The non-linear I-V curves were clearly observed as the voltage reach to 2.0 V for non-irradiated and irradiated samples. This may be attributed to the non-uniform charges by high energy electron irradiation and poor metal contact of the sample. Hysteresis loop form at 2.0 V probably due to the to the charge trapping occurs at the interface of the graphene and SiO2. The reaction of high energy particles lead to creation of more carrier charges that contribute to the increment of conductivity compare to the small number of atom displacement of knock-on collisions with the nuclei of carbon atoms at higher dose. This study provides significant findings on the graphene electrical characteristics when irradiated with high energy (MeV) electron.

Recently, the dielectric breakdown of insulating membranes in aqueous solution has been utilized to fabricate nanopore sensors for various molecular detection applications. Generally, the breakdown...

A new efficient approach for extracting solar cell parameters based on the three main points of the I-V characteristic of the five-parameter model is presented. The proposed method allows extractin...

In this study, Al/p-GaSe/In Schottky diodes (SDs) were fabricated by using a p-type GaSe semiconductor grown by the Brigdman-Stockbarger method. Current–voltage (I–V) measurements of the Al/p-GaSe/In diode were carried out from 100 K to 400 K with steps of 20 K in the +2 V- (−2) V voltage range and in the dark. The characteristic parameters of SDs were calculated from ln(I)-V characteristics according to the thermoionic emission (TE) theory and from modified Norde’s functions depending on the sample temperature. The barrier height (BH) values calculated from ln(I)-V and Norde’s functions were in agreement. The values of BH and ideality factor (IF) calculated from ln(I)-V characteristics for the SD ranged from 0.97 eV and 1.01 at 400 K to 0.45 eV and 2.18 at 100 K, respectively. The value of serial resistance (Rs) calculated from modified Norde’s functions of the SD decreased with increasing temperature. Also, the reverse bias current value of the Al/p-GaSe/In SD under light illumination was higher than the current value in the dark. Thus, the obtained results show that the prepared Al/p-GaSe/In diode might be used as a photodiode in the optoelectronic applications.

The method and measuring installation for determining the actual critical current values in superconductors, at helium temperatures, coming to the market from domestic and foreign manufacturers of composite wire, round or rectangular section, based on the Nb-Ti alloy, are considered.

Forward and reverse current-voltage (I-V) characteristics of commercial rectifying Schottky diodes (SDs) based on silicon carbide (4H-SiC, base layer doping level 3·1015 cm-3) have been studied under irradiation with 0.9 MeV electrons and 15 MeV protons. The starting diodes were characterized by a barrier height of ~1.5 eV and nearly ideal forward and reverse I-V characteristics. It was found that, at doses exceeding the threshold dose Dth, the series differential resistance Rs of the diodes grows as Rs ~ Dm (m = 10-15) and shows no tendency toward saturation. Dth ≈7·1015 cm-2 under electron irradiation, and Dth ≈ 4·1013 cm-2 in the case of irradiation with protons. Heating to 200oC results in that Rs decreases with activation energy of ~1.1 eV and Rs is partly annealed-out with activation energy of ~0.7 eV. The starting Schottky diodes changes only slightly under irradiation, but, possibly, the irradiation leads to an over-compensation of the n-type layer and formation of an additional barrier in the form of a pn junction.