Fabrication and characterization of 2.3eV InGaN photovoltaic devices

In this work we present the design, fabrication and characterization of 2.3 eV InGaN-based solar cells confirming the feasibility of high indium content III-Nitride materials for photovoltaics. Growth of single phase InxGa1-xN for x up to 0.4 is achieved using Molecular Beam Epitaxy (MBE) with flux modulation for active species. The material is characterized by x-ray diffraction and photoluminescence to quantify the layer quality and indium content, while the optical properties are characterized by studying spectral response and absorption. The fabricated devices are then studied for photo-response under AM0 and intense UV spectral conditions to evaluate solar cell characteristics. The dark and illuminated I–V results indicate the existence of significant shunt and series resistances. The causes of these behaviors are known and ultimately resolvable.