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Perovskite materials are used as the core active layer in a variety of devices, including solar cells and radiation detectors, and the performance of these devices is strongly influenced by the thickness of the perovskite active layer. This study compares the performance of photovoltaic cells and radiation detectors with the same device architecture but different perovskite active layer thicknesses. For perovskite solar cells, the power conversion efficiency (PCE) tends to increase with increasing active layer thickness and then decreases beyond a certain limit. On the other hand, the X-ray response characteristics of perovskite X-ray detectors tend to increase continuously with increasing active layer thickness. This means that the collections of total charges generated by photon or radiation are different, and their collection/recombination mechanisms of the charges generated in the perovskite active layer of each device are different. To realize efficient perovskite-based electro-optical devices, optimization of the device architecture, including the active layer thickness, is essential, and this work aims to provide a direction for the development of X-ray detectors in n-i-p device structures. [ABSTRACT FROM AUTHOR]

GaN HEMT devices are sensitive to the single event effect (SEE) caused by heavy ions, and their reliability affects the safe use of space equipment. In this work, a Ge ion (LET = 37 MeV·cm2/mg) and Bi ion (LET = 98 MeV·cm2/mg) were used to irradiate Cascode GaN power devices by heavy ion accelerator experimental device. The differences of SEE under three conditions: pre-applied electrical stress, different LET values, and gate voltages are studied, and the related damage mechanism is discussed. The experimental results show that the pre-application of electrical stress before radiation leads to an electron de-trapping effect, generating defects within the GaN device. These defects will assist in charge collection so that the drain leakage current of the device will be enhanced. The higher the LET value, the more electron–hole pairs are ionized. Therefore, the charge collected by the drain increases, and the burn-out voltage advances. In the off state, the more negative the gate voltage, the higher the drain voltage of the GaN HEMT device, and the more serious the back-channel effect. This study provides an important theoretical basis for the reliability of GaN power devices in radiation environments. [ABSTRACT FROM AUTHOR]

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In most non‐fullerene organic solar cells comprising bulk‐heterojunction active layers, the inter‐domain connectivity of small‐molecule acceptors is generally inferior to those of polymeric donors due to their intrinsic short‐range ordering. This issue is even exacerbated by the physiochemical mismatch between acceptor‐phases and metal‐oxide electron transport layers in most inverted n‐i‐p devices, leading to inefficient electron collection. By pre‐depositing an ultra‐thin acceptor primer layer, it develops a novel acceptor‐enriched‐bottom active layer to reinforce the acceptor‐phase continuity. It is however challenging to preserve the primer layer during non‐orthogonal solvent processing. Thus, sequential n‐type doping is implemented on the surface of the primer layer, which allows to slightly reduce the acceptor solubility by polarity regulation, as well as stabilize the film structure via strong π–π interaction between dopant/host acceptor. Upon acceptor enrichment, higher interfacial electron density enhances the built‐in potential while the enlarged domains suppress both charge‐transfer state and bimolecular recombination. Consequently, the champion device efficiency is greatly improved from ca. 16.1% to 18.0%, mainly resulting from the simultaneously elevated fill factor and short‐circuit current density. [ABSTRACT FROM AUTHOR]

Planar devices and FinFET devices exhibit significant differences in single-event upset (SEU) response and charge collection. However, the charge collection process during SEU in FinFET devices has not been thoroughly investigated. This article addresses this gap by establishing a FinFET SRAM simulation structure and employing simulation software to delve into the charge collection process of FinFET devices during single-event upset. The results reveal substantial differences in charge collection between NMOS and PMOS, and that direct incidence of PMOS leads to the phenomenon of multiple-node charge collection causing SRAM unit upset followed by recovery. [ABSTRACT FROM AUTHOR]

GaN HEMT devices are sensitive to the single event effect (SEE) caused by heavy ions, and their reliability affects the safe use of space equipment. In this work, a Ge ion (LET = 37 MeV·cm2/mg) and Bi ion (LET = 98 MeV·cm2/mg) were used to irradiate Cascode GaN power devices by heavy ion accelerator experimental device. The differences of SEE under three conditions: pre-applied electrical stress, different LET values, and gate voltages are studied, and the related damage mechanism is discussed. The experimental results show that the pre-application of electrical stress before radiation leads to an electron de-trapping effect, generating defects within the GaN device. These defects will assist in charge collection so that the drain leakage current of the device will be enhanced. The higher the LET value, the more electron–hole pairs are ionized. Therefore, the charge collected by the drain increases, and the burn-out voltage advances. In the off state, the more negative the gate voltage, the higher the drain voltage of the GaN HEMT device, and the more serious the back-channel effect. This study provides an important theoretical basis for the reliability of GaN power devices in radiation environments.

A GaN high-electron-mobility transistor (HEMT) was simulated using the semiconductor simulation software Silvaco TCAD in this paper. By constructing a two-dimensional structure of GaN HEMT, combined with key models such as carrier mobility, the effects of a different state, different incidence position, different drain voltage, different LET values, and a different incidence angle on the single-event transient effect of GaN HEMT are simulated. LET stands for the linear energy transfer capacity of a particle, which refers to the amount of energy transferred by the particle to the irradiated substance on the unit path. The simulation results show that for GaN HEMTs, the single-event transient effect is more obvious when the device is in off-state than in on-state. The most sensitive location of GaN HEMTs to the single-event effect is in the region near the drain. The peak transient current increases with the increase in the drain bias and incident ion LET values. The drain charge collection time increases with the angle of incidence of heavy ion. [ABSTRACT FROM AUTHOR]

Carbon electrode perovskite solar cell has great potential in commercial application based on its low cost, superior stability, and facile fabrication process. However, its performance still lags behind that of devices with gold anode, which greatly attributes to the insufficient charge transport and collection at carbon anode side. Herein, efficient anode buffer contact is built by constructing an organic/inorganic composite hole transport bilayer together with strategic carbon precovering/postcovering anode. Adding a charge selective polythiophene (P3HT) layer between perovskite and nickel oxide (NiOx) can reduce charge transfer recombination loss, inhibit moisture infiltration, and crystallographically protect the perovskite underneath from being corroded by carbon paste. Together with a dense and pin-hole free hole transport layer (HTL)/carbon contact through precovering diluted carbon paste, the modified anode buffer interfaces also promote a facilitated charge collection, thus enhancing the photovoltaic performance of low-cost carbon electrode perovskite solar cells to a state-of-the-art value of 20.8% with an enhanced operational stability. This work provides adaptable and robust anode buffer interfaces for efficient, stable and low cost carbon electrode perovskite cells toward commercialization.

Spinel zinc ferrite (ZnFe2O4, ZFO) is a potential photoanode material for photoelectrochemical (PEC) water splitting because of its ideal bandgap (1.9–2.1 eV) and superior chemical stability in aqueous solutions. However, the low charge collection efficiency significantly hinders the improvement in PEC activity. Herein, we report an ultrafast and effective flame activation route to enhance the charge collection properties of ZFO. First, high-temperature flame (> 1300 ℃) facilitated surface and grain boundary diffusions, increasing the grain size and connectivity of the ZFO nanoparticles. Second, the reducing atmosphere of the flame enabled the formation of surface defects (oxygen vacancy and Fe2+), thereby increasing the charge carrier density and surface adsorption sites. Significantly, these two factors promoted charge transport and transfer kinetics, resulting in a 10-fold increase in the photocurrent density over the unactivated ZFO. Furthermore, we deposited a thin Al2O3 overlayer to passivate the ZFO surface and then the NiFeOx oxygen evolution catalyst (OEC) to expedite hole injection into the electrolyte. This surface passivation and OEC deposition led to a remarkable photocurrent density of ~1 mA/cm2 at 1.23 V versus the reversible hydrogen electrode, which is the highest value among all reported ZFO photoanodes. Notably, the NiFeOx/Al2O3/F-ZFO photoanode achieved excellent photocurrent stability over 55 h (96% retention) and superior faradaic efficiency (FE > 94%). Our flame activation method is also effective in improving the photocurrent densities of other spinel ferrites: CuFe2O4 (93 times), MgFe2O4 (16 times), and NiFe2O4 (12 times).

Efficient photocarrier generation and collection are highly desirable for solar‐fuel conversion systems. However, the latter is challenging for many photoelectrodes due to carrier losses happening in the semiconductor‐electrolyte interface and the semiconductor‐substrate interface. To overcome it, a novel Au/CuBi2O4 (CBO)/PtSe2 van der Waals heterojunction photocathode has been developed to boost photocarrier collection. As a result, the ohmic contact at Au/CBO interface shows a low resistance for hole transfer. Meanwhile, while promoting electron transfer, the Van der Waals heterojunction of CBO/PtSe2 interface with energy barrier‐blocked holes. Concurrently, the composite photocathode exhibits significantly enhanced performance: a photocurrent of −0.59 mA cm−2 at 0.5 V versus reversible hydrogen electrode and an H2O2 generation rate of 2.39 mol (Lhm2)−1. This work demonstrates the charge regulation role of Van der Waals heterojunctions in the solar‐fuel system. More broadly, Van der Waals heterojunctions provide an excellent bond‐free approach to creating versatile optoelectronic devices. [ABSTRACT FROM AUTHOR]

• By adjusting the defocusing amount, pulse lasers can obtain ionization traces of different radial sizes at various depths within the device. • Competition between carrier recombination and funneling effects determines the quantity of collected charge. • Both movement precision and off-axis angle influence the quantitative characterization of continuous scan charge collection. Pulsed lasers are employed to simulate Single Event Effects (SEEs) on Earth, with their feasibility empirically validated. In practical applications, it is necessary to correlate laser test results with high-energy particle measurements to accurately predict spatial SEE rates. Most of the current methods rely on charge collection RPP models or nested RPP models for laser-energy particle correlation. These models have not yet accounted for the effect of ionization trace differences. In this paper, ionization traces with different radial dimensions are obtained at different depths inside a bipolar device operational amplifier LM324 by adjusting the defocusing amount of the laser. This study compares charge collection generated by the laser with different characteristic ionization traces and analyzes experimental error factors and the charge collection mechanism. The results indicate that the radial size of the ionization traces inside the device is the main factor affecting the charge collection. Larger radial size of ionization traces on the surface area of the device results in greater charge collection, while smaller radial size of ionization traces in the depletion area and the substrate layer leads to increased charge collection. Additionally, efforts should be made to minimize the effects of movement accuracy errors and off-axis angle errors on the quantitative characterization of the test. [ABSTRACT FROM AUTHOR]

Planar devices and FinFET devices exhibit significant differences in single-event upset (SEU) response and charge collection. However, the charge collection process during SEU in FinFET devices has not been thoroughly investigated. This article addresses this gap by establishing a FinFET SRAM simulation structure and employing simulation software to delve into the charge collection process of FinFET devices during single-event upset. The results reveal substantial differences in charge collection between NMOS and PMOS, and that direct incidence of PMOS leads to the phenomenon of multiple-node charge collection causing SRAM unit upset followed by recovery.

In this paper, the effects of different factors, including the heavy ions striking location, incident angle, linear energy transfer (LET) value, projected range, ambient temperature and bias state, on the single event transient introduced by heavy ions irradiation in the SiGe heterojunction bipolar transistor (HBT) were investigated by the TCAD simulation. The results show that the current transient peak value, collected charge and carrier type of each terminal are changed by the striking location, incident angle and bias state. The current transient peak value and collected charge increase with the LET value, while they decrease with the ambient temperature. When heavy ions vertically irradiate the collector and substrate, the current transient peak value and collected charge increase with the projected range; therefore, the species of heavy ions should be considered in studying the single event effects of the SiGe HBT induced by heavy ions irradiation. The microphysical mechanism of these factors influencing the single event effects of the SiGe HBT is discussed in this work. [ABSTRACT FROM AUTHOR]

This study analyzes the effects of the punch-through stop (PTS) layer and well depth in a bulk FinFET SRAM cell on the fraction of charge generated by an ion impact that is collected by the FinFET channel. More than 1700 3D TCAD simulations have been performed to obtain a detailed map of the sensitivity areas in a full cell 6-T SRAM 22 nm bulk-FinFET process. The influence of the well depth on the charge collected by the drain devices of the SRAM cell has been studied, and it has been concluded that the collected charge can be reduced down to 300% simply by modifying the depth of the well, without affecting the performance of the cell. Different PTS layer depths have been analyzed in order to calculate which value minimizes the impact of the charge generated by an ion during its track along the FinFET body. The simulations carried out allow to conclude that the incorporation of a PTS layer not only reduces the leakage current, but also reduces the amount of charge, delivered by the ion, that reaches the drain region. Simulation results also show that the fraction of the charge generated by the ion impact, which is collected by the drain, mainly depends on the depth of the wells, whereas the PTS layer hardly modifies the collected charge.

A GaN high-electron-mobility transistor (HEMT) was simulated using the semiconductor simulation software Silvaco TCAD in this paper. By constructing a two-dimensional structure of GaN HEMT, combined with key models such as carrier mobility, the effects of a different state, different incidence position, different drain voltage, different LET values, and a different incidence angle on the single-event transient effect of GaN HEMT are simulated. LET stands for the linear energy transfer capacity of a particle, which refers to the amount of energy transferred by the particle to the irradiated substance on the unit path. The simulation results show that for GaN HEMTs, the single-event transient effect is more obvious when the device is in off-state than in on-state. The most sensitive location of GaN HEMTs to the single-event effect is in the region near the drain. The peak transient current increases with the increase in the drain bias and incident ion LET values. The drain charge collection time increases with the angle of incidence of heavy ion.

Constructing heterostructure by coupling structures with a one-dimensional morphology is a promising method to enhance photoelectrodes' charge collection and light absorption properties for photoelectrochemical water splitting. Herein, we aimed to synthesize a BiVO 4 (BVO)/Sb-doped SnO 2 (SSO) nanorods-axial-heterostructure (NAH) via the facile solution-based methods of spin coating and hydrothermal growth. The thicknesses of the BVO layer and SSO nanorods were optimized by controlling the spin coating and hydrothermal growth cycles to maximize photocurrent generation. The resultant BVO/SSO NAH photoanode has a three times greater photocurrent density (2.3 mA cm−2 at 1.23 V vs. the reversible hydrogen electrode) than pristine BVO film (0.75 mA cm−2). This enhanced photocurrent density is attributed to the excellent charge collection (separation + transfer) property induced by the heterointerface (i.e., type II heterojunction) and the bottom single-crystalline SSO nanorods. Furthermore, the BVO/SSO NAH shows the highest photocurrent density of 3.2 mA cm−2, Faradaic efficiency of ∼93%, and long-term stability over 2 h via coupling with FeOOH oxygen evolution electrocatalyst. This study suggests that the axial heterostructure is a superior design platform for developing efficient photoelectrodes. [Display omitted] [ABSTRACT FROM AUTHOR]

Experimental data are presented for the charge collection efficiency for near-electrode interactions in cryogenic germanium detectors, and analyzed in terms of a model involving a phonon wind-driven expansion of the electron-hole cloud generated at the site of energy deposition. Computer simulations reproduce to an excellent accuracy the collection depth profiles as obtained by experiment and their dependence on the collection field and the nature of the electrode. Electrode-dependent effects in particular are explained by differences in the phonon reflection properties at the interface of the Ge crystal and the electrode. [ABSTRACT FROM AUTHOR]

The enhancement of the fill factor in the current generation of perovskite solar cells is the key for further efficiency improvement. Thus, methods to quantify the fill factor losses are urgently needed. Two methods are presented to quantify losses due to the finite resistance of the semiconducting layers of the solar cell as well as its contacts. The first method is based on the comparison between the voltage in the dark and under illumination analyzed at equal recombination current density and results in a voltage‐dependent series resistance. Furthermore, the method reveals the existence of a strong photoshunt under illumination. The second method is based on measuring the photoluminescence of perovskite solar cells as a function of applied voltage. Thereby, the recombination current is determined as a function of voltage from short circuit to open circuit, and the presence of the photoshunt is explained with a high resistance of the electron and/or hole transport layers combined with field screening in the absorber. [ABSTRACT FROM AUTHOR]

The burgeoning field of perovskite solar cells (PSCs) has achieved significant advancements, rivaling traditional photovoltaic technologies. However, efficient, and stable charge collection remains a critical hurdle for commercial deployment. This review aims to provide a comprehensive overview of various charge collection materials and their implications in perovskite photovoltaics. We assess state-of-the-art materials like indium tin oxide (ITO), conductive polymer, metal-based thin film, carbon-based alternatives, and more, exploring their optical properties, mechanical flexibility, electrical conductivity, and associated fabrication costs. While ITO remains the most commonly used due to its high transparency and conductivity, its scarcity and high-cost limit its scalability. Metal-based electrodes offer excellent conductivity and are emerging as leaders in applications requiring mechanical flexibility, but their permeation and interaction within perovskites need to be overcome. Carbon- and polymer-based materials offer stability and low cost but often suffer from lower conductivity. Each material class presents its own set of challenges, which must be addressed for real-world applications. This review also delves into innovative solutions, aiming to overcome these challenges, concluding by discussing the future potential and the key areas of research to realize durable, efficient, and cost-effective perovskite photovoltaics. [Display omitted] • The charge collection material is a key role in optimizing performance of perovskite solar cells. • This review meticulously examines state-of-the-art charge collection materials in perovskite solar cells. • The review prospects a comprehensive overview of charge collection materials for efficient perovskite photovoltaics. [ABSTRACT FROM AUTHOR]

The features of collecting minority charge carriers formed on the tracks of single particles in a layer of silicon at a depth of 200 to 250 nm under shallow trench isolation (STI) in a CMOS two-input NAND gate and an inverter as part of the majority gate are simulated using 3D TCAD utilities. Charge collection by groups of two NMOS and two PMOS transistors, as well as one PMOS transistor, when collecting charge from tracks with input track points into the silicon's active areas of the transistors and surrounding the STI at distances of 40 to 700 nm from the edge of the transistor groups, is investigated. The charges transferred by current pulses from these distances ranges from 50 to 4.5 fC at LET = 60 MeV cm2/mg and from 80 to 11 fC at LET = 90 MeV cm2/mg. Increasing the distance of the track's entry point into the trench isolation by 200 nm from the area of the group of transistors that collect charge from the track reduces the amplitude value of the current pulse that transfers the charge from the track by factors of 1.8 to 2.0 times and also halves the value of the collected charge. At LET = 90 MeV cm2/mg, the amplitude values of voltage pulses at the node that outputs the charge with two NMOS or two PMOS transistors of a two-input NAND gate in the track entry points ranging from 40 to 200 nm can decrease by factors of 1.5 to 2.0 with an increase in the distance of the track entry point by 100 nm from the edge of the transistor area. Error pulses at the output of the majority gate with an amplitude of 0.7 to 1 V are formed at the track entry points directly in the active areas of the NMOS and PMOS transistors and in tracks with entry points into the STI layer at a distance of 40 to 100 nm from the edge of the active areas, mainly during charge collection by the NMOS transistors. [ABSTRACT FROM AUTHOR]

Since neutrons are electrically neutral, the methods used to detect neutrons generally rely on secondary charged particles, which are produced by the interaction of neutrons and neutron conversion materials (such as 6LiF, 10B). In this report, the SRIM code has been used to analyze the ionization properties of $\alpha $ particles and 3H particles traveling through the Silicon Carbide (SiC) diode, and subsequently, the final Bragg ionization distribution has been obtained. Next, according to the obtained ionization distribution of secondary particles, the linear energy transfer (LET) distribution of the secondary particles is extraced accurately. Finally, based on the distribution of LET, Technology Computer Aided Design (TCAD) simulations are utilized to analyze the transient current pulses of thin-film-coated and trench-type SiC diodes. In addition, the effects of particle energy and applied reverse bias on the output pulse characteristics of SiC diodes are also explored. Essentially, this paper augments the understanding of output response from SiC neutron detectors, and for trench-type detectors, the order of output current pulse amplitude decreases significantly and has a long-tail. Therefore, the trench-type detectors not only need a more advanced fabrication process but also require the design of dedicated readout electronics. [ABSTRACT FROM AUTHOR]

A promising material for semiconductor detectors of ionizing radiation is CdTe:Cl which allows obtaining detectors with high resistivity ρ and electron mobility μn. During operation, the detector materials may be exposed to neutron irradiation, which causes radiation defects to form in crystal lattice and deep levels to appear in the band gap, acting as centers of capture and recombination of nonequilibrium charge carriers, thus reducing the detection capability. The aim of this study was to use computer simulation to investigate the mechanisms of the influence of such radiation defects on the electrophysical properties (ρ, μn) of CdTe:Cl and the charge collection efficiency η of radiation detectors based on this material. The simulations were based on the models tested for reliability. It was found that the increase of the CdTe:Cl resistivity ρ during low-energy neutrons bombardment and at the initial stages of high-energy neutrons bombardment is caused by an increase in the concentration of radiation donor defect Z (with an energy level EC – 0.47 eV), presumably interstitial tellurium, which shifts the Fermi level into the middle of the band gap. The sharp rise of ρ observed at high-energy neutron bombardment is probably caused by the restructuring of the crystalline structure of the detector material with a change in the lattice constant and with an increase of the band gap, accompanied by a change in the conductivity properties. The degradation of the detector properties of CdTe:Cl during neutron irradiation is due to the capture and recombination of nonequilibrium electrons at radiation defects: Te interstitial, Te substitutional at the cadmium site, on tellurium vacancies and cadmium vacancies. The degradation of electron mobility μn can be caused by the scattering of electrons at microscopic areas of radiation defect clusters. The increase in concentration of the defects over the volume of the crystal at their uniform distribution of up to 1016 cm–3 does not significantly affect the electron mobility at room temperature.

The results of modeling the processes of masking noise arising from the collection of charge by transistors from the tracks of single ionizing particles with a linear energy transfer (LET) of 60 MeV cm2/mg are presented in a majority element based on the NAND CMOS logic. They were modeled using the 3D TCAD physical models of CMOS transistors according to the design standard of 65 nm bulk technology with the shallow trench isolation of transistor groups. Charge collection from the track leads to the formation of noise pulses. The majority element has an original topological structure, in which the transistors of the output gate 3NAND are inserted one-by-one into the corresponding transistor groups of the two-input 2NAND elements. A feature of the majority element is masking the noise (blocking their transmission to the output) that occurs when the charge is collected from the track after switching the element at the inputs from 0 to 1 and before switching the element at the inputs from 1 to 0. When masking, no noise pulses appear at the output of the majority element. [ABSTRACT FROM AUTHOR]

The results of modeling the elements of a triple majority gate based on the CMOS NAND logic elements are presented. Modeling is carried out using the 3D TCAD of physical models of CMOS transistors according to the design standard of 65-nm bulk technology with the shallow trench isolation (STI) of transistor groups when the charge is collected by transistors from the tracks of single ionizing particles with linear energy transfer (LET) in the range from 10 to 90 MeV cm2/mg. The collection of a charge from the track leads to the formation of noise pulses. The majority gate is made on 18 transistors and has an original topological structure, in which the transistors of the 3NAND output logic element are inserted one-by-one into the corresponding groups of transistors of the three 2NAND input elements. This reduces the duration of the pulse noise at the output of the majority element with input signals A = B = C = 0 due to the joint collection of a charge from the particle track by transistors of series-connected 2-input NAND and 3-input NAND logic elements. A feature of the majority element is noise masking (blocking the transmission to the output of noise pulses that occur on its internal NAND nodes) when the signals at the inputs of the element are A = B = C = 1. With signals at the inputs of element A = B = C = 0, the duration of the noise pulses are in the range of 50 to 200 ps with the LET to the track of 60 to 90 MeV cm2/mg with the track input points into NMOS transistors; and 250–400 ps, with the track input points into PMOS transistors. [ABSTRACT FROM AUTHOR]

• A two-phase flow electricity charge separator (TPECS) is proposed that enables charge separation and selective charge collection. • The working principle of TPECS is elucidated based on flow visualization and electrical signals. • The average power of TPECS with various types (single, multi, and stacked multi) is analyzed. • The stacked multi TPECS lights up 93 LEDs validating practicality. This study introduces the concept of generating electricity by selectively separating and moving charges in water. If positive and negative charges in a fluid can be separated and discharged to create a potential difference, it is a unique approach to generate electricity and has the advantage of providing direct current output. We proposed a new design that maximizes the potential difference by first discharging the free charge in the diffusive layer inside the water through an external electrode, and then electrically separating and discharging the fixed charge near the channel surface by selectively using solid surfaces with different surface potentials. As a proof of concept, we fabricated a channel-type charge separator and verified its working mechanism through quantitative experimental data analysis. Examination of the electrical signals validated the symmetry of signals from individual electrodes, affirming selective collection of separated charges in a fluid. We verified the performance and practicality of the two-phase flow electricity charge separator (TPECS) under different flow conditions. It was also possible to stack the channels, and an electrical power of up to 2.99 μW was produced from a structure of 12 stacked channels. Capacitor charging was executed employing the 12 stacked channels. The charging rate of the 2.2nF capacitor reached 9.46 V/s, facilitating the illumination of 93 red LEDs. [ABSTRACT FROM AUTHOR]

In this article, we present a new method to mitigate the effect of the charge collected by trigate FinFET devices after an ionizing particle impact. The method is based on the creation of an internal structure that generates an electrical field that drives the charge generated by the ion track out of the sensitive device terminals. This electrical field is generated with the insertion of complementary doped regions near the active region of the device. We analyze the influence of the distance of those regions to the device, their depth into the substrate and their doping concentration to determine the optimal implementation which minimizes the collected charge. The impact on the device performance in terms of leakage current, threshold voltage, maximum transconductance and subthreshold voltage swing has also been investigated. Our results show that the added structures introduce negligible effects in performance degradation and total leakage current, at the cost of a small increase in area. The simulations performed with technology computer-aided design numerical (TCAD) tools in 22nm bulk FinFET technology show that the amount of charge collected by the device terminals can be reduced up to 50% for a linear energy transfer (LET) of 60 MeV-cm2/mg.

The two main variants of a CMOS Triple Majority Gate (TMG) for redundant computing systems used on exposure to single nuclear particles are modeled and compared. This is a variant on 2-input 2AND and 2OR logic gates and a variant on three 2-input 2AND gates and one 3-input 3OR gate. It is modeled using 3D TCAD tools, including the physical modeling of the linear energy transfer (LET) to the particle's track. The transistors are made using 65-nm bulk silicon CMOS technology with shallow trench isolation (STI). The durations of the interference pulses at the outputs of the NAND, AND, NOR, and OR gates, the dependence of the duration on the pulse shape, and the duration of the delays from the moment the track appears to the moment when the pulse front rises to the threshold amplitude value with the dependence to the particle's track in the range of 10 to 90 MeV cm2/mg are compared. Tracks with the direction normal to the crystal surface are used. The mechanism of reducing (correcting) the duration of the interference pulses at the outputs of the AND and OR gates with an increase in the dependence to the track is analyzed. Due to the correction effect, the duration of the interference pulses at the output of the AND gate, OR gate and, accordingly, at the TMG when collecting the charge from the track with the input point in the corresponding gate does not exceed 150 ps at the output of the 2AND gate; 50–100 ps, at the output of the 2OR gate; or 250–350 ps, at the output of the 3OR gate. The minimum interference duration is observed in the TMG version, performed only on 2-input AND and OR gates. [ABSTRACT FROM AUTHOR]

A pulsed laser has been effectively applied in dose rate effects simulation for its stable pulse output, low cost, simple operation, and lack of ionizing risks for users. The conversion factor (CF) was proposed to describe the equivalence between the responses generated by pulsed laser and pulsed ionizing radiation (e.g., γ-ray). Previously, the peak photocurrent was commonly used to calculate the CF and establish the equivalent relationship. But there are a number of shortcomings such as narrow effective equivalent range, inadequate information of waveform, as well as low accuracy of simulations. In this article, an improved method for obtaining the CF by using the charge collection as the equivalent factor is proposed, which considers not only the peak photocurrent but also the temporal information of the waveform. The advantages of the proposed method are proved both in theory and in experiments, including broader equivalent range and higher simulation accuracy. [ABSTRACT FROM AUTHOR]

• Effect of various crystalline structures of MAPbI (3-n) Br n perovskite on the photovoltaic properties has been investigated. • PVC fabricated with MAPbI 3 yielded highest PCE of 29.8% under indoor LED light source @1000 lux. • MAPbBr 3 has demonstrated a remarkably high V OC of 1.15 V under indoor light source. • MAPbI 3 and MAPbBr 3 have shown better operational stability of the devices. Organic-inorganic hybrid lead halide perovskite materials with the general formula MAPbI 3-n Br n (n = 0, 1, 2, and 3) exhibiting a range of crystal structures and a wide range of optical bandgaps are explored for their potential to harvest energy from ambient light sources. The replacement of I− with Br− is found to transform the perovskite crystal structure from the tetragonal for MAPbI 3 to the pseudo cubic for MAPbI 2 Br and MAPbIBr 2 and cubic for MAPbBr 3 while increasing the optical bandgap from 1.59 eV to 2.31 eV. Photovoltaic cells (PVCs) are constructed using these perovskites and are found to exhibit power conversion efficiencies (PCEs) of 29.83 (MAPbI 3), 23.75 (MAPbI 2 Br), 21.47 (MAPbIBr 2), and 19.94% (MAPbBr 3) under LED light illumination (1000 lux; ~0.371 mW cm−2), with a record high open-circuit voltage (V OC) of 1.15 V being observed for the MAPbBr 3. The effect of crystal structure variation on the charge carrier mobility, trap states, recombination losses, photovoltaic properties, and operational stabilities has been investigated systematically under indoor illumination. Overall, this work provides a clear vision on the influence of perovskite crystal structures upon the photovoltaic properties and shows a pathway to achieve high V OC in perovskite PVCs under low-intensity ambient light sources. [ABSTRACT FROM AUTHOR]