Abstract
Modern requirements for high-efficiency solar cells increase interest in the development of new materials and structures, in particular the use of GaN/porous-GaAs/GaAs composite materials and heterostructures, which allow to improve the efficiency and stability of solar energy conversion. To determine the photovoltaic characteristics of the GaN/porous-GaAs/GaAs photoconverter, a system of equations is used, including the Poisson equation, the diffusion equation, and the charge conservation equation. The simulation results of GaN/porous-GaAs/GaAs solar cells using PC1D software showed values of short-circuit current ISC = 33.2 mA, open-circuit voltage VOC = 1.022 V, fill factor FF = 83.4% and efficiency η = 28.3% In order to optimize the parameters of the solar cell, simulations were carried out with a change in the thickness of the GaN layer, the doping levels of the GaN and porous-GaAs layers. It was established that with a thickness of the GaN layer of 1.6 μm, the efficiency of the solar cell reaches a maximum value of 29.1%. The maximum efficiency was achieved when the GaN layer was doped with 1·1017 cm−3 and was 28.4%. An increase in the temperature of the solar cell leads to a decrease in the open-circuit voltage and an increase in recombination losses, which is reflected in the decrease in the efficiency of the GaN/porous-GaAs/GaAs photoconverter from 29.8% at 270 K to 23.0% at 370 K.