Improvement of current blocking for GaN-based LEDs by treatments of Ar plasma on p-GaN surface

In this paper, we successfully demonstrated that the Ar plasma-damaged p-GaN surface increased the resistance of ITO/P-GaN contact serving as injection current deflection layer under the electrode pad. It was found that both of the V_f at 20 mA were approximately 3.3V. Under a 20mA current injection, it was found that output powers were 9.8 and 11.08mW for conventional LEDs and LEDs with Ar plasma damaged p-GaN surfaces respectively. We can increase the LED output power by 13% by inserting the p-GaN surface damaged by Ar plasma under the electrode pad. It was also found that after testing 72 hours, the half lifetimes of conventional LEDs and LEDs with Ar plasma damaged p-GaN surface were about 49% and 55% of the initial intensity, respectively.