Optical and Thermal Analyses of Thin-Film Hexagonal Micro-Mesh Light-Emitting Diodes

Vertical thin-film light-emitting diodes (LEDs) with integrated micro-mesh arrays are reported. By removing the sapphire substrate through laser lift-off, vertical current conduction becomes possible, improving current spreading capability and thus electrical properties. Compared with the as-grown device, the thin-film micro-mesh LEDs emits 61% more optical power, attributed to enhanced light extraction through the micro-mesh, evidence of which is provided by confocal imaging. At 100 mA, the enhancement factor rises to >;100% attributed to low junction temperatures due to efficient heat conduction as verified by infrared thermometric imaging.