Extraction Efficiency Enhancement of GaN-Based Light-Emitting Diodes by Microhole Array and Roughened Surface Oxide

Abstract

The light-output power of GaN-based light-emitting diodes (LEDs) was enhanced by microhole array pattern and roughened GaO(x) film grown on the exposed surface. The GaO(x) film was grown by photoelectrochemical (PEC) oxidation via H(2)O and formed a naturally rough oxide surface and GaO(x)/GaN interface. Compared with that of conventional broad-area LEDs, the output power of the microhole array LED and the surface-oxidized microhole array LED increased by 1.38 and 1.82 times at 20-mA forward current, respectively. The results show that the microhole array pattern with the roughened surface oxide method could significantly enhance light extraction efficiency and be a candidate for manufacturing high-efficient low-cost GaN-based LEDs.