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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.

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.

This paper presents a theoretical study of the effect of the nature of the carrier escape from quantum dots (QDs) on the performance of InAs/GaAs QD solar cells (QDSCs), based on numerical simulations. Excitonic and non-excitonic dynamics of electrons and holes are considered in the modeling, by assuming identical or separate time constants for the intersubband carrier transfer processes in the ground and excited states. It is shown that the excitonic capture and escape allow us to explain the non-additive characteristic of the QD photocurrent, observed when the total photocurrent of the cell is much lower than the sum of the photocurrents contributed separately by the barrier and the nanostructures. This behavior is practically eliminated in the non-excitonic case. The correlated dynamics under the nonexcitonic scenario is analyzed by calculating the device sensitivity to small changes introduced in the escape time of electrons. It is stated that the non-variation of the QD photocurrent with this parameter could be interpreted as a consequence of either a correlated electron-hole escape from QDs, or a dominant recombination over the other involved processes. The ideality factor of the different QDSCs studied is also calculated from simulations under both concentrated sunlight and dark conditions. The obtained results are in line with experimental measurements published in the literature.