Open-circuit-voltage enhancement of the III-V super-lattice solar cells under optical concentration

Abstract

The GaAs single junction solar cell containing the nano-structure of multiple quantum wells (MQWs) or super-lattice (SL) consist of the InGaAs/GaAsP strain-balanced wells and barriers grown by MOVPE was evaluated under the concentrated illumination. Defining the concentration ratio CJ as a ratio of saturated current density ratio of under the concentrated illumination versus 1SUN, the increasing dependency of open-circuit-voltage (VOC) on CJ showed steeper tendency for only SL inserted sample than the conventional multiple quantum wells (MQWs) case. This result indicated that the carrier transport enhancement by tunneling effect by thinning each barriers contribute the VOC increment at the high concentrated illumination. © 2012 American Institute of Physics.