In this work, InGaN/GaN multiple quantum well (MQW) light emitting diodes (LEDs) wafer with two emission peaks were grown by metalorganic chemical vapor deposition (MOCVD). X-ray diffraction (XRD), Ruthford backscattering (RBS), cathodoluminescence (CL), electroluminescence (EL) and emission microscope (EM) measurements were performed to study the recombination mechanism of InGaN QWs. The green spots and blue floccules in EM images were assigned to In-rich quantum dots (QDs) and modified QW by piezoelectric field. The wavelengths for both blue and green emissions do not shift until the injection level reach to 2 x 10(4) mA/cm(2). In CL images, the modified QWs assigned by EM and EL have a broad band tail expanding to 526 nm. (c) 2006 Elsevier B.V. All rights reserved.