Radiation response of the electrical characteristics of GaAs solar cells with quantum dot layers

GaAs PiN solar cells with 50 In_0.4Ga_0.6As quantum dot (QD) layers were irradiated with 1 MeV electrons up to 1×10¹⁶ /cm². The change in their electrical characteristics under an air mass zero (AM 0) was studied using an in-situ measurement system. The open circuit voltage (V_OC) for InGaAs 50 QD solar cells remains 90 % of its initial value after electron irradiation at a fluence of 1×10 ¹⁶/cm². On the other hand, the short current circuit (I_SC) and maximum power (P_MAX) for 50 QD solar cells decrease to approximately 80 and 60 % of their initial value after the same irradiation, respectively. The recovery of the electrical characteristics of both InGaAs 50QD solar cells as well as GaAs PiN solar cells without the QD layers degraded by electron irradiation are observed under AM0 light illumination at room temperature after irradiation.