Growth of periodic micropits InGaN‐based LED structure on wet‐etch patterned sapphire substrate

Growth of periodic micropits InGaN-based light emitting diode (LED) structure on wet-etch patterned sapphire substrate (WPSS) was introduced. Two-step growth of GaN on the triangle shape of WPSS promotes the ability to control the density/size of honeycomb shape GaN template and resulting in the threading dislocation density of 8-9×106 cm-2. Moreover, this template also was acting as the seeds to conduct the periodic distribution of micropits InGaN/GaN multiple quantum wells (MQWs). Spatially and spectrally resolved luminescence from periodic micropits LED is obtained using near-field scanning optical microscope (NSOM). The results revealed that the excited carrier has facilitated the confinement at the horizontal MQW region rather than in the inclined facet MQW. Consequently, intensity of the light emitting from the horizontal region is much higher than that of the inclined facets region. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)