Measuring the Junction Temperature of GaInP/GaInAs/Ge Multijunction Solar Cells Using Photoluminescence

Abstract

The junction temperatures of the three individual subcells of InGaP/InGaAs/Ge solar cells were measured using photoluminescence (PL) with three different excitation lasers. With the illumination of an extra xenon-mercury lamp, the linear relationship between the PL energy and the illumination level is clearly observed and advantageously used for deriving the junction temperature. Using the Varshni relationship between the PL peak energy and the heat-sink temperature allows us to determine the junction temperature in each subcell. (C) 2011 The Japan Society of Applied Physics