III-V Multijunction Solar Cells - New Lattice-Matched Products And Development Of Upright Metamorphic 3J Cells

摘要

AZUR SPACE's current CPV product 3C40C is an advanced lattice-matched In_(0.50)Ga_(0.50)P/In_(0.01)Ga_(0.99)As/Ge triple junction (3J) solar cell. Recently, efficiencies up to 41.2percent (450-600 X AM 1.5d) have been confirmed for this 40percent-class product. This kind of solar cell structure has now reached its practical efficiency limit and went into production in 2010. AZUR offers customized cell structures, regarding size and grid design, as well as anti-reflection coatings adapted to the individual CPV system. Integration grades from diced wafers up to assemblies, such as dense arrays, are available. Special features and production results for the 3C40C structure are presented in this work. In order to further push efficiencies beyond 42percent AZUR has successfully transferred the upright metamorphic cell from Fraunhofer ISE and advances this concept now for production. First results on metamorphic 3J solar cells at AZUR SPACE and the actual potential of this concept will be discussed. A target efficiency of 42percent seems to be realistic.