Method of processing sapphire substrate

摘要

To provide a method of processing a sapphire substrate, where reduction in luminance of light emitting devices can be suppressed if a sapphire substrate is divided into individual light emitting devices by irradiation of a laser beam, a pulsed laser beam having a small pulse energy of 0.6 muJ to 10 muJ, and an extremely small pulse width in a range of femto-second is irradiated to the sapphire substrate while a condensing point is positioned within each of regions corresponding to predetermined division lines on the sapphire substrate so that affected zones are formed, thereby the laser beam can be irradiated even at a high peak power density of 4x10¹³ W/cm² to 5x10¹⁵ W/cm², consequently each of the affected zones can be formed at only a desired condensing point within the sapphire substrate, and necessary processing can be performed while damage to nitride semiconductors or the sapphire substrate is minimized.