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All-inorganic perovskite solar cells (PSCs) with inverted p-i-n configuration have not yet reached the high efficiency achieved in the normal n-i-p architecture. However, the inverted all-inorganic PSC are more compatible with the fabrication of tandem solar cells. In this work, a theoretical study of all-inorganic PSCs with inverted structure ITO/HTL/CsPbIxBr3−x/ETL/Ag, has been performed by means of computer simulation. Four p‐type inorganic materials (NiO, Cu2O, CuSCN and CuI) and three n-type inorganic materials (ZnO, TiO2 and SnO2) were used as hole and electron transport layers (HTL and ETL), respectively. A band gap of 1.78 eV was used for the CsPbI x Br3−x perovskite layer. The simulation results allow identifying that CuI and ZnO are the most appropriate materials as HTL and ETL, respectively. Additionally, optimized values of thickness, acceptor density and defect density in the absorber layer have been obtained for the ITO/CuI/CsPbI x Br3−x /ZnO/Ag, from which, an optimum efficiency of 21.82% was achieved. These promising theoretical results aim to improve the manufacturing process of inverted all-inorganic PSCs and to enhance the performance of perovskite–perovskite tandem solar cells.

Sumario: Introducción - Fundamentos teóricos - Simulación numérica - Resultados - Conclusiones - Apéndices.

All species of scorpions can inject venom, some of them even with the possibility of killing a human. Therefore, early detection and identification are essential to minimize scorpion stings. In this paper, we propose a novel automatic system for the detection and recognition of scorpions using computer vision and machine learning (ML) approaches. Two complementary image-processing techniques were used for the proposed detection method to accurately and reliably detect the presence of scorpions. The first is based on the fluorescent characteristics of scorpions when exposed to ultraviolet light, and the second on the shape features of the scorpions. Also, three models based on ML algorithms for the image recognition and classification of scorpions are compared. In particular, the three species of scorpions found in La Plata city (Argentina): Bothriurus bonariensis (of no sanitary importance), Tityus trivittatus, and Tityus confluence (both of sanitary importance) have been researched using a local binary-pattern histogram algorithm and deep neural networks with transfer learning (DNNs with TL) and data augmentation (DNNs with TL and DA) approaches. A confusion matrix and a receiver operating characteristic curve were used to evaluate the quality of these models. The results obtained show that the model of DNN with TL and DA is the most efficient at simultaneously differentiating between Tityus and Bothriurus (for health security) and between T. trivittatus and T. confluence (for biological research purposes)., Facultad de Ingeniería, Instituto de Investigaciones en Electrónica, Control y Procesamiento de Señales, Centro de Estudios Parasitológicos y de Vectores

[EN] The effects of the offset level and of the doping level in the perovskite layer upon both the reverse saturation current (J0) and the series resistance (Rs) of p-p-n perovskite solar cells have been researched in this paper, using five different materials such as spiro-OMeTAD, Cu2O, CuSCN, NiO and CuI, as Hole Transporting Material (HTM). The analysis was carried out by means of the single and double-diode models of a solar cell and of genetic algorithms based on optimization technique, in order to extract the desired parameters. The minor degradation of J0 and Rs has been found for the condition offset equal to zero and for the highest doping level in p-type perovskite layer. Also, a comparison has been made of the behavior of two reverse saturation currents (J01 and J02). The power conversion efficiency (PCE) has shown to be more strongly dependent on J02 than on J01. Results obtained in this work can be used to improve the manufacturing process of these devices., This work was partially supported by the National Council Research (CONICET), Argentina, by the Universidad Nacional Arturo Jauretche, Argentina, by the Universidad Nacional de Quilmes, Argentina, by the Universidad Nacional de La Plata, Argentina and by the Ministerio de Economía y Competitividad (Grant ENE2016-77798-C4-2-R), Spain

[EN] In this paper, a theoretical study of different p-p-n perovskite solar cells has been performed by means of computer simulation. Effects of the offset level upon the power conversion efficiency (PCE) of these devices have been researched using five different materials such as spiro-OMeTAD, Cu2O, CuSCN, NiO and CuI, as Hole Transporting Layer (HTL). The Solar Cells Capacitance Simulator (SCAPS)-1D has been the tool used for numerical simulation of these devices. A strong dependence of PCE has been found with the difference between the Maximum of the Valence Band of the HTL and perovskite materials, and with the doping level in p-type perovskite layer. A minimum value of hole mobility in the HTL has been also found, below which the PCE is reduced. Efficiencies in the order of 28% have been obtained for the Cu2O/Perovskite/TiO2 solar cell. Results obtained in this work show the potentiality of this promising technology., This work was partially supported by the Universidad Nacional de Quilmes, Argentina, by the Universidad Nacional Arturo Jauretche, Argentina, by the Universidad Nacional de La Plata, Argentina, by the National Council Research (CONICET), Argentina, and by the Ministerio de Economia y Competitividad (Grant ENE2016-77798-C4-2-R), Spain.

Fil: Cappelletti, Marcelo Angel. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - La Plata. Instituto de Investigaciones en Electronica, Control y Procesamiento de Senales. Universidad Nacional de La Plata. Instituto de Investigaciones en Electronica, Control y Procesamiento de Senales; Argentina. Universidad Nacional Arturo Jauretche; Argentina

The electrical parameters degradation of n-type GaAs solar cells exposed to radiation from high-energy particles has been analyzed by means of computer simulation. Specifically, the radiation damage caused by electron upon the diffusion and recombination currents and the series resistance of the solar cells with different base carrier concentrations have been researched using the NRL method, the PC1D program and a home-made numerical code based on genetic algorithms. Results obtained are useful to predict the behavior of these devices under extreme operating conditions.

An iterative method based on numerical simulations was developed to enhance the proton radiation tolerance and the responsivity of Si PIN photodiodes. The method allows to calculate the optimal values of the intrinsic layer thickness and the incident light wavelength, in function of the light intensity and the maximum proton fluence to be supported by the device. These results minimize the effects of radiation on the total reverse current of the photodiode and maximize its response to light. The implementation of the method is useful in the design of devices whose operation point should not suffer variations due to radiation.

This paper presents a theoretical study about quantum dot solar cells by means of numerical simulations, considering different doping levels in the intrinsic region of the cells, with the aim of evaluating the effect on the device's power conversion efficiency. Results of simulations performed over GaAs solar cells with InAs quantum dots, based on two different fabrication processes, are reported. The donor doping density in the intrinsic region was ranged from 1013 to 1017 cm-3. It is shown that, for a doping level of 7×1015 cm-3, the contribution of larger sized quantum dots to the photocurrent is increased by 50%, a very promising result in the search for new designs with higher efficiencies. Fil: Cedola, Ariel Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Plata. Facultad de Ingeniería. Departamento de Electrotecnia. Grupo de Est.s/materiales y Disposit.electronicos; Argentina Fil: Gioannini, Mariangela. Politecnico di Torino; Italia Fil: Cappelluti, Federica. Politecnico di Torino; Italia Fil: Cappelletti, Marcelo Ángel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Plata. Facultad de Ingeniería. Departamento de Electrotecnia. Grupo de Est.s/materiales y Disposit.electronicos; Argentina Fil: Peltzer y Blanca, Eitel Leopoldo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Plata. Facultad de Ingeniería. Departamento de Electrotecnia. Grupo de Est.s/materiales y Disposit.electronicos; Argentina

En este trabajo se muestra el estudio realizado sobre materiales que serán utilizados en el diseño de una celda solar para su aplicación en el ciclo de producción de hidrógeno, también en este contexto se han estudiado compuestos capaces de almacenar el hidrógeno producido, de manera de cerrar el círculo propuesto de generación y almacenamiento de hidrógeno. En la primera etapa, se realizó el estudio de materiales semiconductores mediante primeros principios, con esta herramienta se estudiaron las propiedades electrónicas de los sistemas M:TiO2 (donde M: metales de transición 3d). En la segunda etapa, se llevó a cabo la modelización de una celda solar multijuntura, empleando los materiales obtenidos en la primera etapa. Mediante el diseño propuesto de la estructura de la celda solar se logró una eficiencia del 10% para la producción del hidrógeno. Finalmente, en la tercera y última etapa, una vez obtenido el hidrógeno, se realizaron estudios para determinar cuáles serían los materiales más viables para retener y liberar el H. Con esta finalidad, se estudiaron series de hidruros binarios y ternarios, con diferentes estructuras cristalinas, para determinar que compuesto presenta una mejor perspectiva para el almacenamiento de H., Facultad de Ingeniería

The radiation resistance in InGaP/GaAs/Ge triple-junction solar cells is limited by that of the middle GaAs sub-cell. In this work, the electrical performance degradation of different GaAs sub-cells under 1 MeV electron irradiation at fluences below 4 × 1015 cm−2 has been analyzed by means of a computer simulation. The numerical simulations have been carried out using the onedimensional device modeling program PC1D. The effects of the base and emitter carrier concentrations of the p- and n-type GaAs structures on the maximum power point have been researched using a radiative recombination lifetime, a damage constant for the minority carrier lifetime and carrier removal rate models. An analytical model has been proposed, which is useful to either determine the maximum exposure time or select the appropriate device in order to ensure that the electrical parameters of different GaAs sub-cells will have a satisfactory response to radiation since they will be kept above 80% with respect to the non-irradiated values. Fil: Cappelletti, Marcelo Ángel. Universidad Nacional Arturo Jauretche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ingeniería. Departamento de Electrotecnia; Argentina Fil: Cedola, Ariel Pablo. Universidad Nacional de La Plata. Facultad de Ingeniería. Departamento de Electrotecnia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina Fil: Peltzer y Blanca, Eitel Leopoldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ingeniería. Departamento de Electrotecnia; Argentina

A theoretical study of the electrical performance of p-on-n GaAs sub-cells under AM0, irradiated with 1 MeV electrons, has been carried out by means of computer simulation. Effects of both base and emitter carrier concentration upon radiation resistance of these devices have been researched. From analysis it is possible to determine the highest electron fluence to which the electrical parameters of the solar cell, with well-known base and emitter carrier concentrations, are reduced simultaneously in less than 20% from their non-irradiated values. Results presented in this paper are important in order to contribute to the design of radiation-hardened devices.

The performance of crystalline silicon n + / p / p + and n / n / p + solar cells under AM0 spectrum,irradiated with 1 MeV electrons at fluences below 10 17 cm −2 has been analyzed by means ofcomputer simulation. The software used, fully developed by the authors, solves numerically inone dimension under steady-state conditions, the Poisson and continuity equationsself-consistently. The influence of constructive characteristics and different levels of hazardousenvironmental work conditions on the maximum power point of over 150 devices has beeninvestigated. The study has allowed the authors to propose a useful analytical model related tothe constructive characteristics of the device such as polarity, base resistivity and totalthickness, with the aim of examining the electrical performance of Si space solar cells. Resultspresented in this paper are important in order to contribute to the design of radiation-hardeneddevices. 1. Introduction Taking into account the urgent need to make the most ofalternative energy sources, the study of semiconductor devicesthatcanprovidepoweratlowoperatingcost,suchassolarcells,is extremely important at the present time. Deep studies aboutso-calledthirdgenerationsolarcells,focusedonnewmaterialsand technologies such as intermediate band, quantum dots andhot-carrier devices [1–4], are being carried out with the aimof reducing the cost and increasing the efficiency with respectto the first generation, i.e. crystalline silicon (c-Si) solar cells.However, in present times a considerable amount of researchin the field of the photovoltaic cells is still dominated by theconventional c-Si devices.For space power applications, where the devices areexposed to irradiation of high energy particles, multijunction(MJ) solar cells based on III–V technologies havedemonstrated higher conversion efficiencies and radiation-resistance than c-Si devices [5–7]. Nevertheless, c-Si solarcells have proven to offer a worthy operational reliability andcosteffectivenessasaspacepowersource[8–10]andthereforefurther research in this topic is still required.Every different solar cell structure from a given material,total thickness, base resistivity and polarity (p- or n-type),is expected to respond differently as a function of radiation.Therefore, each device must undergo some kind of irradiationtest to determine the degradation characteristics. Nowadays,precise techniques of modeling and simulation have becomefundamental tools to predict and to improve the responseof electronic devices under different operation conditions,offering valuable knowledge at a much lower cost and in lesstime than experimentation.In order to contribute to the design of radiation-hardeneddevices, this paper presents a theoretical study of the behaviorof different c-Si n

In this paper, we present a study about Si and GaAs space solar cells by means of numerical simulations. We have investigated the variations of the short-circuit current, open circuit voltage and maximum power point, before and after the devices were irradiated with 10 MeV protons and fluences between 109 and 1013 p+ /cm2. The simulation results allow to obtain the optimum solar cell with specific requirements for space applications. Fil: Cappelletti, Marcelo Ángel. Universidad Nacional de La Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Casas, Guillermo. Universidad Nacional de La Plata; Argentina. Universidad Nacional de Quilmes; Argentina Fil: Cedola, Ariel Pablo. Universidad Nacional de La Plata; Argentina Fil: Peltzer y Blanca, Eitel Leopoldo. Universidad Nacional de La Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

In this paper, a theoretical study of the electrical parameters degradation of different n-type GaAs sub-cells for InGaP/GaAs/Ge triple junction solar cells irradiated with 1 and 5 MeV electrons has been performed by means of computer simulation. Effects of base carrier concentration upon the maximum power point, short-circuit current, open circuit voltage, diffusion current, recombination current and series resistance of these devices have been researched using the displacement damage dose method, the one-dimensional PC1D device modeling program and a home-made numerical code based on genetic algorithms. The radiative recombination lifetime, damage constant for minority-carrier lifetime and carrier removal rate models for GaAs sub-cells have been used in the simulations. An analytical model has been proposed, which is useful to describe the radiation-induced degradation of diffusion current, recombination current and series resistance. Results obtained in this work can be used to predict the radiation resistance of solar cells over a wide range of energies. Fil: Cappelletti, Marcelo Ángel. Universidad Nacional de La Plata. Facultad de Ingeniería. Departamento de Electrotecnia. Grupo de Estudio de Materiales y Dispositivos Electrónicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional Arturo Jauretche; Argentina Fil: Casas, Guillermo. Universidad Nacional de La Plata. Facultad de Ingeniería. Departamento de Electrotecnia. Grupo de Estudio de Materiales y Dispositivos Electrónicos; Argentina. Universidad Nacional de Quilmes; Argentina Fil: Morales, Daniel Martin. Universidad Nacional Arturo Jauretche; Argentina Fil: Hasperué, Waldo. Universidad Nacional Arturo Jauretche; Argentina. Universidad Nacional de La Plata. Facultad de Informática. Instituto de Investigación en Informática Lidi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina Fil: Peltzer y Blanca, Eitel Leopoldo. Universidad Nacional de La Plata. Facultad de Ingeniería. Departamento de Electrotecnia. Grupo de Estudio de Materiales y Dispositivos Electrónicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina

An iterative method applied to enhance the proton radiation tolerance and the responsivity of PIN photodiodes was developed. The method allows to calculate optimal values of the intrinsic layer thickness and the incident light wavelength, in function of the light intensity and the maximum proton fluence to be supported by the device. These results minimize the effects of radiation on the total reverse current of the photodiode and maximize its response to light. The implementation of the method is useful in the design of devices that will not suffer variations from its operation point due to radiation.

In the present work, a complete numerical analysis of the influence of deep-trap levels on the dark current of silicon PIN photodiodes under 1 MeV neutron radiation was done. Results corroborate that energy levels near the mid-gap affect to a great extent the dark current. Radiation tolerances of undoped and gold-doped devices were compared through simulations. It has been concluded that gold in silicon reduces the neutron-induced damage. Finally, a model to calculate the dark current of irradiated devices doped with deep-impurities is presented.

This work focuses on study of radiation induced displacement damage effects on silicon PIN photodiodes at both, dark and illumination conditions, by mean of numerical simulations. For fluences greater than a certain limiting value, relation between photocurrent and dark current decreases below ten, leading to an undesirable device operation. An iterative method is proposed for design optimization of PIN photodiodes to be used under irradiation, that minimize radiation effects on total reverse current and maximize device response to incident light.

In the present work, the influence of deep-trap levels on the dark current of silicon PIN photodiodes under 1 MeV neutron radiation has been investigated by means of a complete numerical analysis. The computational code used for simulations, developed by the authors, numerically solves the coupled Poisson and continuity equations on a 2D domain to obtain the behavior of electronic devices. Recombination through deep levels in the bandgap is described by the Shockley–Read–Hall (SRH) theory. Defects caused by radiation are quantified in terms of the damage coefficient K for the minority carrier lifetime. The effects of the radiation studied are atomic displacement damages. Results corroborate that the dark current is strongly affected by energy levels close to the midgap. A relationship between the current damage rate and the trap level location in the silicon bandgap was obtained. A model to calculate the dark current of irradiated devices doped with deep impurities is presented. Simulations have allowed the comparison of radiation tolerances of undoped and gold-doped devices. The higher gold density has shown a marked improvement of the hardness of the devices to radiation effects.

A computer program for the simulation of semiconductor devices has been developed and applied to the analysis of radiation effects on Si PIN photodiodes. The study has allowed the authors to propose useful analytical models related to such optical and electrical device parameters as peak spectral response and dark current. Peak spectral response has shown a marked dependence on device layers dimensions. Dark current has demonstrated linear increase with intrinsic layer length and proton-radiation fluence. But the most important obtained result has been the determination of a particular set of semiconductor P-, I- and N-layer thicknesses, for given values of total device length and incident light intensity, that minimize radiation effects during photodiode operation in space environments up to high particle fluences.