Shape designing for light extraction enhancement bulk-GaN light-emitting diodes

摘要

Light extraction efficiency enhancement of bulk GaN light-emitting diodes (LEDs) in the shape of truncated-pyramid has been investigated. Compared with the reference LEDs, an enhancement of up to 46% on the light output power from rectangle-shaped LEDs chip with the inclination angle (～44°) has been observed. Compared with the common triangle-shaped and hexagon-shaped LEDs, large size of conventional rectangular LEDs shaped with truncated-pyramid shows more obvious enhancement in light extraction efficiency. In addition, the ray-tracing simulations results show that light extraction efficiency was influenced not only by inclination angle but also by dimension size.