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Group III nitrides are promising materials for light emitting diodes (LEDs). The occurrence of structural defects strongly affects the efficiency of these LEDs. We investigate the optical properties of basal plane stacking faults (BFSs), and the assignment of specific spectral features to distinct defect types by direct correlation of localized emission bands measured by cathodoluminescence in a scanning electron microscope with defects found in high resolution (scanning) transmission electron microscopy and electron beam induced current at identical sample spots. Thus, we are able to model the electronic structure of BSFs addressing I-1, I-2, and E type BSFs in GaN and AlGaN with low Al content. We find hints that BSFs in semipolar AlGaN layers cause local changes of the Al content, which strongly affects the usability of AlGaN as an electron blocking layer in nitride based LEDs.
The change of electricity supply from conventional to renewable energy sources is a challenge for the whole society. This transition causes an increase of volatility in electricity supply and therefore threatens both, grid stability and, also, electricity price stability. Besides cost-intensive countermeasures such as grid expansions and power-to-X storage technology, the incentivized change in electricity use (energy demand flexibility) is a promising approach. Today, when it comes to production matters, energy is considered as a resource which is immediately available on demand. In contrast, future scenarios draw a picture, in which electric energy will become a resource that requires planning and control. Energy flexible factories will be an important part of our society with an important ecological and social impact. The paper presents a transdisciplinary approach to shape a sustainable electricity supply in the discourse with regional stakeholders from a technical, ecological and social background.