Enhancement of Light Output Power and Modification of Beam Profile in InGaN/GaN Light Emitting Diodes with Micro Polygon Column Shaped Transparent

We report on the fabrication of GaN-based light-emitting diodes (LEDs) with micro-polygon (MPC) obtained by selective area growth (SAG) using the technique of metal organic chemical vapor deposition (MOCVD). The SAG makes it possible to control the density size and position of the micro polygon columns. The facet structure consists of a polygon column covered with {1101} facets columns with rough occur on the (0001) surface. The light output power of the MPC-LED was 53% higher than conventional LED. In addition the light extraction efficiency of InGaN/GaN LEDS is significantly improved owing to the photon path length is shorter. It is possible to modify the beam profile via shaped transparent layer. Thus, this structure can provide photons with multiple chances of escaping from the LEDS surfaces. (C) 2010 The Japan Society of Applied Physics