InGaN/GaN Structures: Effect of the Quantum Well Number on the Cathodoluminescent Properties

We have prepared epitaxial scintillator structures with different number of InGaN/GaN quantum wells (QW). Photo- and cathodoluminescence spectra show that increasing the number of quantum wells from 10 to 30 helps both to enhance the fast blue emission from QW, and to suppress undesired slow lower-energy emission. We explain this through formation of V-pits on the surface, which feature thinner QW on their side walls and thus separate charge carriers from dislocations found in their centre.