Strong light extraction enhancement in GaInN light-emitting diodes by using self-organized nanoscale patterning of $p$-type GaN

We report on a self-organized nanoscale patterning method by using oblique angle deposition to enhance the light extraction in a GaInN light-emitting diode (LED). The method offers one-step processing with good controllability of the feature size and density of the nanopatterns by varying the deposition angle during oblique angle deposition, eliminating the need for photolithography and annealing. A 5-nm-thick silver (Ag) film, when deposited by using oblique angle deposition, spontaneously forms a nanoscale island-like morphology on the substrate. This method is used to texture $p$-type GaN with nanoscale features, which results in increased light extraction from a GaInN LED. At 100 mA, the nanotextured LED shows a 46% higher light output than a standard LED with unpatterned (planar) $p$-type GaN.