Simulation of Parameters of Coaxial Solar Cells Based on Si and InP Nanowires

The use of photovoltaic solar energy converters with nanowire solar cells is a promising direction for further development of photovoltaics. Along with this, significant interest in the properties of Si, InP, GaAs, InGaN nanowires as elements of high-efficiency photoconverters has formed a new direction of nanowire photovoltaics. The most relevant is the study of structural, optical, electrical, temperature and other characteristics of semiconductor nanowires. The paper presents the results of numerical simulation of coaxial p-i-n structures of solar cells based on Si and InP nanowires. The geometry of the 3D structures, light and dark current-voltage characteristics are designed using Silvaco TCAD tools. Within the framework of the drift-diffusion transport model with Fermi-Dirac statistics, the admissible values of the electrical parameters such as the open-circuit voltage UOC, short-circuit current density JSC, maximum power Pm, fill-factor FF, photovoltaic efficiency and others are obtained. The temperature dependence of the current-voltage characteristics and electrical parameters is investigated. The temperature coefficients of the open-circuit voltage, short-circuit current density, fill-factor and efficiency for coaxial nanowire solar cells based on Si and InP are determined in the temperature range from 300 to 400 K. It is concluded that the thermal stability of the electrical parameters for InP-based photovoltaic converter is high, which is characteristic of direct band gap semiconductors. The obtained results of numerical simulation are in good agreement with the experimental data and can be used to predict the properties of nanowire solar cells.