InGaN-Based High-Power Flip-Chip LEDs With Deep-Hole-Patterned Sapphire Substrate by Laser Direct Beam Drilling

A high-performance flip-chip light-emitting diode (LED) with deep-hole-patterned sapphire substrate was fabricated by laser direct beam drilling. The output power of the LED was measured to be as high as 145 mW at a forward current of 350 mA, which is improved by 19% compared to that of the reference LED. This significant enhancement of the LED with deep-hole-patterned sapphire is attributed to the increase of extraction efficiency, resulting from the increase in photon escape probability due to enhanced light scattering at the deep-hole pattern.