Degradation of InGaN-based MQW photodetectors under 405 nm laser excitation

Carlo de Santi (1) , Matteo Meneghini (1) , Alessandro Caria , Ezgi Dogmus (2) , Malek Zegaoui (2) , F Medjdoub (2) , Enrico Zanoni (1) , Gaudenzio Meneghesso (1)

1 Unipd - Università degli Studi di Padova = University of Padua
2 IEMN - Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520

Within this paper we analyze the reliability of 25x 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.

Domaines: Sciences de l'ingénieur [physics]

Carlo de Santi, Matteo Meneghini, Alessandro Caria, Ezgi Dogmus, Malek Zegaoui, et al.. Degradation of InGaN-based MQW photodetectors under 405 nm laser excitation. European Symposium on Reliability of Electron Devices, Failure Physics and Analysis 2017, Sep 2017, Bordeaux, France. ⟨hal-03298875⟩