We characterize the radiation‐induced damage of InGaP/GaAs/Ge solar cells for various proton irradiation energies and fluences using conventional current‐voltage (I‐V) measurements, external quantum efficiency, and a noncontact time‐resolved photoluminescence (PL) technique. From the I‐V curves, we obtain the conversion efficiency of the entire device. The external quantum efficiency showed that the short‐circuit current is only determined by the top InGaP subcell. To obtain accurate information about the point of maximum power, a new PL technique is introduced. The PL time decays of the InGaP and GaAs subcells are measured to obtain the characteristic decay time constants of carrier separation and recombination. We empirically verify that the time‐resolved PL method can be used to predict the electrical conversion efficiency of the subcells. We find that the limiting subcell at the point of maximum power is different from that for short‐circuit current. Radiation damage in unexpected regions of the device is revealed using this optical method.

中文翻译：

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使用光致发光衰减评估辐射损坏的三结太阳能电池的子电池功率转换效率

我们使用常规电流-电压（I-V）测量，外部量子效率和非接触时间分辨光致发光（PL）技术来表征InGaP / GaAs / Ge太阳能电池对各种质子辐照能量和注量的辐射诱导损伤。从IV曲线，我们可以获得整个器件的转换效率。外部量子效率表明，短路电流仅由顶部的InGaP子电池决定。为了获得有关最大功率点的准确信息，引入了一种新的PL技术。测量InGaP和GaAs子电池的PL时间衰减，以获得载流子分离和重组的特征衰减时间常数。我们凭经验验证了时间分辨PL方法可用于预测子电池的电转换效率。我们发现最大功率点的限制子电池与短路电流的限制子电池不同。使用这种光学方法可以发现设备意外区域的辐射损伤。