Modeling of GaInP/GaAs/Ge and the inverted-grown metamorphic GaInP/GaAs/GaInAs triple-junction solar cells

In this work, based on the advanced drift and diffusion theory with improved tunneling junction model, two-dimensional modeling for the GaInP/GaAs/Ge and the inverted-grown metamorphic GaInP/GaAs/GaInAs triple-junction solar cells are performed by using a commercial software, the Crosslight APSYS. Basic physical quantities like band diagram, optical absorption and generation are obtained and characteristic results such as IN curves, current matching, fill factor, efficiency etc under one-sun and multi-sun illumination are presented. Some of the modeling results generally agree with the published experimental results for both TJ cells. Comparative analyses are made with these two TJ cells and optimization approaches are discussed with respect to minority carrier lifetime, front anti-reflection coating, and top contact grid size and spacing.