the highest reported efficiency (67%) at its wavelength (380 nm), was analyzed with the
three-dimensional atom probe. The results reveal gross discontinuities and compositional
variations within the quantum well layers on a 20–100 nm length scale. In addition, the
analysis shows the presence of indium in the Al y Ga 1− y N barrier layers, albeit at a very
low level. By comparing with analogous epilayer samples, we suggest that the quantum well …