Resumen de Degradation of InGaN-based MQW solar cells under 405 nm laser excitation
C. De Santi, M. Meneghini, A. Caria, E. Dogmus, M. Zegaoui, F. Medjdoub, E. Zanoni, G. Meneghesso
Abstract Within this paper we analyze the reliability of 25 × multi quantum well InGaN-based devices, designed to be used as high power photodetectors or in multi-junction solar cells. Under stress with monochromatic excitation at 405 nm by means of a laser diode, we detect degradation at optical power levels significantly above the common AM1.5 spectrum; the main degradation modes are a reduction in short circuit current and in open circuit voltage, and an improvement in fill factor. The analysis of the wavelength-dependent EQE highlights, as a consequence of stress, the increase in concentration of a deep level compatible with the yellow luminescence in gallium nitride, suggesting that gallium vacancies may play a role in the degradation of the detectors.
