Power Enhancement of GaN-Based Flip-Chip Light-Emitting Diodes with Triple Roughened Surfaces

Abstract

The flip-chip light emitting diodes (FC-LEDs) with triple roughened surfaces were fabricated comprising top surface sapphire textured layer, interface patterned sapphire layer, and bottom naturally textured p-GaN layer. Light extraction efficiency was enhanced by such triple textured layers. The light output power of FC-LEDs was increased 60% (at 350 mA current injection) compared to that of conventional FC-LEDs by implementing the triple roughened surfaces. The enhancement efficiency can be simulated and the simulated results showed the same trend as the results of experiment. (C) 2009 The Japan Society of Applied Physics