Performance-enhanced vertical LED using laser irradiation treatment to control wafer-level n-GaN protrusion arrays

A controllable, mask-free, and wafer-level surface texturing method is proposed, which is applied to n-GaN protrusion array using laser irradiation treatment targeting to achieve high-performance vertical light-emitting diodes. The size and density of the n-GaN protrusions could be modified by controlling the energy density and pulse number of laser irradiation. Measurement results of current-voltage and light output power (LOP) reveal that the textured surface structure increases the LOP up to 47.89% at an injection current of 350 mA without affecting the current spread, such an enhancement is attributed to a higher probability that light could escape from the textured n-GaN surface.