Enhancing light output power of InGaN-based light-emitting diodes with an embedded self-textured oxide mask structure

A 460 nm InGaNGaN light-emitting diode (LED) with a self-textured oxide mask (STOM) structure was demonstrated using metal-organic chemical vapor deposition (MOCVD). The fabricating of STOM employed a low temperature (850C) GaN template to form a textured surface onto which the SiO₂ mask was fabricated. Measurements of optical and electrical properties of the LED showed that the corrugated STOM structure increases light scattering and reflection to enhance light output, and also reduces the dislocations to inhibit non-radiative recombination. Under an injection current of 20 mA, the forward voltages of the STOM-LED and conventional LED (C-LED) were nearly identical at 3.41 V. The leakage current of the STOM-LED was lower than that of C-LED, and the STOM-LEDs light output power was approximately 47 higher (at 20 mA). This significant improvement was attributed to the enhanced light extraction via the STOM array.