The fabrication procedure of a moth-eye patterned sapphire substrate (MPSS), which can enhance the light extraction
efficiency of nitride-based light emitting diodes (LEDs) has been examined. The optimization of surface morphology
after the etching of the MPSS for high-quality GaN growth was also performed. Then, we fabricated MPSS samples with
a fixed pitch of 460nm, and corn height ranging from 50 to 350nm. The light extraction efficiency of blue-LEDs grown
on a series of MPSS was enhanced about 1.4 times compared with the devices grown on a flat sapphire substrate. We
found that if corn height exceeds 150nm, the MPSS effect is sufficiently observed.