Title :
Study of InGaN/GaN Light Emitting Diodes With Step-Graded Electron Blocking Layer
Author :
Chao Liu ; Zhiwei Ren ; Xin Chen ; Bijun Zhao ; Xingfu Wang ; Yian Yin ; Shuti Li
Author_Institution :
Lab. of Nanophotonic Functional Mater. & Devices, South China Normal Univ., Guangzhou, China
Abstract :
Step-graded AlGaN electron blocking layers (EBLs) have been designed to replace the original AlGaN EBL in blue light emitting diodes (LEDs). The step-graded EBL with increasing Al composition along the growth direction (IEBL) leads to inferior optical performance in the fabricated LEDs, whereas the step-graded EBL with decreasing Al composition (DEBL) results in enhanced light output power and reduced efficiency droop, compared with the original EBL. The simulation results indicate enhanced hole injection and electron confinement by DEBL, which accounts for improved performance. On the contrary, insufficient electron blocking and hole injection by IEBL lead to inferior performance.
Keywords :
III-V semiconductors; aluminium compounds; charge injection; gallium compounds; indium compounds; light emitting diodes; wide band gap semiconductors; InGaN-GaN-AlGaN; LED; blue light emitting diodes; efficiency droop; electron confinement; growth direction; hole injection; light output power; optical performance; step-graded electron blocking layer; Aluminum gallium nitride; Charge carrier processes; Electron optics; Gallium nitride; Light emitting diodes; Optical device fabrication; Power generation; Electron blocking layer; efficiency droop; light emitting diodes;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2013.2290124
