Micro-Chip Shaping for Luminance Enhancement of GaN Micro-Light-Emitting Diodes Array

Significant luminance enhancement of GaN micro-light-emitting diode (
\(\mu \)
LED) array was achieved by micro-chip shaping (
\(\mu \)
CS) technique. The
\(\mu \)
CSs with a shaped angle of 70° and an etched depth of 1
\(\mu \)
m on the sidewall of
\(\mu \)
LEDs with 10-, 16-, and 50-
\(\mu \)
m pixel sizes, respectively, refract light rays through sidewalls into the light extraction cone and consequently improve the luminance. The
\(\mu \)
CSs enhance more luminance on
\(\mu \)
LED with small sizes. The maximum efficiency improvement on the
\(\mu \)
CS
\(\mu \)
LED array is over 45% compared with the vertical sidewall
\(\mu \)
LED array. Furthermore, the efficiency improvement exceeds 48% measured within ±15° extraction cone. The ray-tracing simulation also confirms the
\(\mu \)
CS effect.