Improved Output Power of InGaN-Based Ultraviolet LEDs Using a Heavily Si-Doped GaN Insertion Layer Technique

Abstract

Abstract-In this paper, a high quality ultraviolet lightemitting diodes (UV-LEDs) at 375 nm was developed using a heavy Si-doping technique with metal organic chemical vapor deposition. By using high-resolution X-ray diffraction, the full width at half-maximum of the rocking curve shows that the GaN film inserting a heavily Si-doped GaN layer (Si-HDL) had high crystalline quality. From the transmission electron microscopy image, the threading dislocation density was decreased after inserting a Si-HDL between undoped and n-doped GaN layers by nanoscale epitaxial lateral overgrowth. As a result, a much smaller reverse current and a higher light output were achieved. The improvement of light output at an injection current of 20 mA was enhanced by 40%. Therefore, we can use an in-situ nano pattern without complex photolithography and etching process and improve the internal quantum efficiency of UV-LEDs.Index Terms-Internal quantum efficiency, metal-organic chemical vapor deposition, nanoscale epitaxial lateral overgrowth, ultraviolet light emitting diodes.

Epitaxial Growth and Characterization of AlInN-Based Core-Shell Nanowire Light Emitting Diodes Operating in the Ultraviolet Spectrum

“…Until recently, fundamental and applied research approaches for light-emitters, have essentially focused on the use of InGaN and AlGaN alloys in the active region for near UV 15,16 and UV photonic devices, respectively, while the approach of using different III-nitride UV materials is relatively unexplored. Identifying and developing the potential of alternative UV materials will be critical to make further progress in development of deep UV emitters.…”