III–V compound semiconductors consist of elements out of the main groups III and V of the periodic table. Through proper mixing of the elements, materials with a wide range of bandgaps are available and can be realized in excellent crystal quality. The highest efficiencies of any photovoltaic technology, so far, have been reached with solar cells consisting of such III–V compound semiconductors. This is in particular enabled by stacking solar cells of several III–V compound semiconductors, which absorb different parts of the solar spectrum. These III–V multi-junction solar cells have become standard in space and in terrestrial concentrator systems. The variety of materials as well as an extensive technological toolbox has already led to the realization of diverse solar cell architectures. The current landmark is the Ga0.50In0.50P/Ga0.99In0.01As/Ge triple junction, which only contains lattice-matched layers. This MOVPE-grown device has achieved a record efficiency of 41.6% and is commercially available with efficiencies around 40% under concentrated sunlight. Due to the mature development status of this device new concepts are being investigated to increase the efficiencies further. Methods in the technological toolbox have been used and combined intensively in recent years to realize material combinations, which allow a more efficient use of the solar spectrum. Several approaches have already reached efficiencies higher than the lattice-matched triple-junction solar cell. The aim of this chapter is to give an introductory overview of III–V multi-junction solar cells with a special emphasis on the origins of high efficiencies, the technological toolbox and some exemplary solar cell architectures. Innovative ideas and methods such as metamorphic and inverted growth, wafer-bonding, different substrates, nanostructures, different growth technologies and new materials are discussed.
jiang, G., Bi, J., Song, M., Liu, J., Xiong, W., & Huang, M. (2013). III-V Multi-Junction Solar Cells. In Optoelectronics - Advanced Materials and Devices. InTech. https://doi.org/10.5772/50965