Degradation of InGaN-based MQW solar cells under 405 nm laser excitation. (September 2017)

• Record Type: Journal Article
• Authors: De Santi, C.; Meneghini, M.; Caria, A.; Dogmus, E.; Zegaoui, M.; Medjdoub, F.; Zanoni, E.; Meneghesso, G.
• Is Part Of: Microelectronics and reliability. Volume 76/77(2017)
• Page Start: 575
• Page End: 578
• Publication Date: 2017-09
• Subjects: Electronic apparatus and appliances -- Reliability -- Periodicals; Miniature electronic equipment -- Periodicals; Appareils électroniques -- Fiabilité -- Périodiques; Équipement électronique miniaturisé -- Périodiques; Electronic apparatus and appliances -- Reliability; Miniature electronic equipment; Periodicals; 621.3815
• DOI: 10.1016/j.microrel.2017.06.072
• Languages: English
• ISSNs: 0026-2714

Abstract

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. Highlights: InGaN-based MQW devices are reliable high power photodetectors. Degradation consists of a decrease in short circuit current. The maximum output power from the detector is reduced by the stress. Stress enhances the photocurrent signal from the yellow luminescence region. Gallium vacancies may play a role in the degradation.