Improved performance of near-ultraviolet light emitting diodes on selectively etched GaN templates

An approach that dramatically improved the performance of near-ultraviolet InGaN-based light-emitting diodes (NUV-LEDs) was proposed using the selectively etched GaN (SE-GaN) template, which was fabricated via a combination of patterned sapphire substrate (PSS), defect selective etching, SiO₂ deposition and chemical-mechanical planarization. The dislocation density of n-type GaN regrown on the SE-GaN template can be reduced to 1.3 × 10 ⁵ cm^-2 by concentrating threading dislocations (TDs) within undoped GaN and terminating the propagation of concentrated TDs. When operated with an injection current of 350 mA, the output power of the NUV-LED fabricated on SE-GaN template was 13% higher than that of NUV-LED fabricated on PSS.