Effects of Gallium-Phosphide and Indium-Gallium-Antimonide semiconductor materials on photon absorption of multijunction solar cells

Abstract

The main challenge in the photovoltaic industry is making the solar cells more cost effective. Single junction solar cells can only absorb a certain wavelength of the solar spectrum, hence produce less efficiency. In contrary multijunction solar cells direct sunlight towards matched spectral sensitivity by splitting the spectrum into smaller slices. The high efficiency multijunction photovoltaics made up of III-V semiconductor material alloys with high optical sensitivity and ideal combination of band-gaps increase absorption of photons, creates more electron-hole pairs, and hence increase the efficiency of the solar cell. National Renewable Energy Laboratory (NREL), US Department of Energy (DOE) and many leading research organizations all over the world are investing money in the design of III-IV multijunction solar cell projects. In this paper, we introduce a novel multijunction photovoltaic cell based on GaP/InGaAs/InGaSb, and compare it with existing single-junction and multijunction cells. We observe that the inclusion of GaP and InGaSb layers in our design has made a significant improvement in absorption of solar energy in the entire spectral range, thus resulting in higher efficiency.