MEASUREMENT OF SUBCELL CAPACITANCE IN TRIPLE JUNCTION SOLAR CELLS WITH PULSED ILLUMINATION

摘要

The evolution of the subcell capacitance of triple junction solar cells upon 3 MeV electron irradiation is studied. Photocurrent is induced subcell specific using a sequence of spatially homogeneous, monochromatic light pulses. The used method is based on the externally measured transient voltage, which allows to calculate the depletion layer capacitance. Capacitance-voltage curves for each subcell are obtained. From these curves, the base layer effective doping density and thus the carrier removal rate are extracted for the top and middle subcell. Additionally, the built-in voltage and its degradation is measured.