Improved Output Power of GaN-Based Vertical Light Emitting Diodes Fabricated with Current Blocking Region Formed by O-2 Plasma Treatment

Abstract

We report on the formation of current blocking regions by O-2 plasma treatment to reduce current crowding at the active region above the p-type electrodes of GaN-based vertical light emitting diodes (LEDs). The forward voltage and reverse current (at -5 V) of the plasma-treated LEDs slightly increase with increasing aging time. The output power (at 350 mA) of the plasma-treated LEDs is enhanced by 26% as compared to that of reference LEDs and is comparable to that of LEDs with SiO2 current blocking layers. It is shown that the output power (at 700 mA) of the plasma-treated LEDs is degraded by less than 2% of the initial value after 500 h. (C) 2011 The Japan Society of Applied Physics