We investigated the effects of thermal annealing and sulfide passivation on the electrical characteristics of GaN-based light-emitting diodes (LEDs) whose active regions were integrated with a plasma-etched microhole array resembling a photonic crystal structure. Thermal annealing removed most plasma damage in the near-surface bulk region, whereas (NH4)2S treatment only passivated the defect states at the immediate surface, each producing a partial recovery of the electrical characteristics. It was found that annealing at 700 °C used in conjunction with prolonged sulfide passivation eliminated all the effects of plasma damage and resulted in a complete suppression of surface leakage in the microperforated LEDs.