Structures based on GaAs(Sb)(N) semiconductor alloys for high efficiency multi-junction solar cells

Abstract

III-V multi-junction solar cells (MJSCs) have hold record conversion efficiencies for many years, which is currently approaching 50 %. Theoretical efficiency limits are calculated using optimum designs with the right lattice constant-bandgap energy combination, which requires a 1.0-1.15 eV bandgap semiconductor material lattice-matched to GaAs/Ge. Insertion of such a material layer in a 4-junction MJSC could lead to an efficiency of 60 % under solar concentration, which would represent a significant breakthrough in photovoltaics. Therefore, 1.0-1.15 eV bandgap materials that can be grown lattice-matched to GaAs/Ge are being nowadays intensively researched. Pero la vida no se acaba (ni empieza) en el ISOM. También quisiera agradecer a los profesores que a lo largo del camino me metieron el gusanillo por la ciencia y a las personas xii con las que di mis primeros pasos en el mundo de la investigación: Bianchi Méndez, Emilio Nogales y Alberto Moure. Al Ministerio de Economía y Competitividad por concederme la beca FPI 2014 (BES-2014-068130) que ha permitido la realización de esta tesis, y a todos los que con su trabajo han contribuido a su desarrollo: el