Experimental improvement of concentrator LPE GaAs solar cells for operation at 1000 suns with an efficiency of 26.2%

Concentration using III-V solar cells is one of the best approaches to reduce PV costs. Consequently, the general purpose of this work is the achievement of the highest efficiency at 1000 suns with an enhanced LT-LPE (low temperature liquid phase epitaxy) growth method presenting several advantages such as low cost, lack of contaminants and easy industrialisation. Results of different batches of GaAs LT-LPE terrestrial concentrator solar cells manufactured are presented, compared and thoroughly discussed. The study is focused on the variation of the semiconductor structure, manufacturing process and encapsulation that resulted in an efficiency of 26.2% at 1004 suns (measured at NREL and assuming linearity of short-circuit current with irradiance). This efficiency is to our knowledge the highest in the world for a single junction solar cell at the 1000-2000 concentration range.