Study of structural defects limiting the luminescence of InGaN single quantum wells

InGaN quantum well (QW) structures with different thicknesses have been characterised by means of cathodoluminescence (CL) in the scanning electron microscope and transmission electron microscopy (TEM), in order to study the structural defects that limit the device operation. Misfit dislocations appear as non-radiative centres in the CL images and compete with the quantum-well related luminescence. The luminescence red shift with increasing QW thickness has been found to be influenced by composition fluctuations.