Luminescence properties of dislocations in α-Ga<sub>2</sub>O<sub>3</sub>

Dislocations in epitaxial lateral overgrown α-Ga2O3 are investigated using hyperspectral cathodoluminescence spectroscopy. The dislocations are associated with a reduction of self-trapped hole-related luminescence (ca. 3.6 eV line) which can be ascribed to their actions as non-radiative recombination sites for free electrons, to a reduction in free electron density due to Fermi level pinning or to electron trapping at donor states. An increase in the intensity of the ca. 2.8 eV and 3.2 eV lines are observed at the dislocations, suggesting an increase in donor–acceptor pair transitions and providing strong evidence that point defects segregate at dislocations.