Effect of 2D photonic structure patterned in the LED surface on emission properties

► Influence of large and short period 2D PhC structures patterned in the LEDs surface was documented. ► Large period structure (2.4 μm) achieved light extraction efficiency improvement based on diffraction on surface roughness. ► Short period (470 nm) PhC structure is working as an effective radiation outcoupler using photonic band gap effect. ► 2D PhC LEDs show evident improvement of the light extraction efficiency based on different light outcoupling mechanisms.