High efficiency GaN LEDs with submicron-scale 2Dperiodic structures directly fabricated by laser interference ablation

We report the investigation of directly ablating submicron-scale 2D periodic structure method on the p-layer of blue GaN light-emitting diode (LED) by laser interference. Hexagonal lattice structures on the p-layer surface of GaN LED are fabricated by three beam laser interference and the air hole radius can be changed by adjusting the laser fluence. The structure with a period of 400 nm, hole radius of 180 nm, and depth of 78 nm is patterned with the laser fluence of 215 mJ/cm2. Experimental results coincide well with the simulation, and reveal that the patterned LED get a maximum enhancement of 55.7% in light output power compared to flat LED.