Sharp has achieved the world’s highest solar cell conversion efficiency of 35.8% using a triple-junction compound solar cell. Unlike silicon-based solar cells, the most common type of solar cell in use today, the compound solar cell utilizes photo-absorption layers made from compounds consisting of two or more elements such as indium and gallium. To boost the efficiency of triple-junction compound solar cells, it is important to improve the crystallinity (the regularity of the atomic arrangement) in each photo-absorption layer (the top, middle, and bottom layer). It is also crucial that the solar cell be composed of materials that can maximize the effective use of solar energy.
Sharp has now succeeded in forming an InGaAs layer with high crystallinity by using its proprietary technology for forming layers. As a result, the amount of wasted current has been minimized, and the conversion efficiency, which had been 31.5% in Sharp’s previous cells, has been successfully increased to 35.8%.
