Spatially and spectrally resolved photoluminescence of InGaN/GaN quantum wells grown by metalorganic chemical vapor deposition was studied with near-field scanning optical microscopy and transmission electron microscopy. High-spatial-resolution near-field scanning optical microscopic images showed bright blue quantum well emission around V defects and yellow emission inside the defects. The transmission electron microscopic data suggested that the spatial distribution of blue luminescence was partly due to dislocation gettering by V defects. The yellow emission was attributed to the Ga vacancy-impurity complexes trapped inside V defects.

Spatial Variation of Photoluminescence and Related Defects in InGaN/GaN Quantum Wells. M.S.Jeong, Y.W.Kim, J.O.White, E.K.Suh, M.G.Cheong, C.S.Kim, C.H.Hong, H.J.Lee: Applied Physics Letters, 2001, 79[21], 3440-2