Photoluminescence and cathodoluminescence of light emitting diode samples with various InGaN/GaN multi-quantum-well active structures and a range of dislocation density (about 7 x 108/cm2 to about 9 x 109/cm2) were investigated. Results indicated that threading dislocations had an impact on the luminescence of GaN thin films and act as a non-radiative recombination center. It was also observed that the optical emission was affected by the multi-quantum-well structure such as the number of quantum wells.

Effects of Dislocations on the Luminescence of GaN/InGaN Multi-Quantum-Well Light-Emitting Diode Layers. Y.S.Choi, J.H.Park, S.S.Kim, H.J.Song, S.H.Lee, J.J.Jung, B.T.Lee: Materials Letters, 2004, 58[21], 2614-7