Enhanced Optical Power of InGaN/GaN Light-Emitting Diode by AlGaN Interlayer and Electron Blocking Layer

Author

Lee, Sang-Jun ; Cho, Chu-Young ; Hong, Sang-Hyun ; Han, Sang-Heon ; Yoon, Sukho ; Kim, Sung-Tae ; Park, Seong-Ju

Author_Institution

Sch. of Mater. Sci. & Eng., Gwangju Inst. of Sci. & Technol., Gwangju, South Korea

Volume

24

Issue

22

fYear

2012

Firstpage

1991

Lastpage

1994

Abstract

We report on the effect of an AlGaN interlayer with a low Al composition, which is inserted between multiple quantum wells (MQWs) and an AlGaN electron blocking layer (EBL) in light-emitting diodes (LEDs). The band diagram shows that this interlayer reduces the hole barrier height between the last GaN barrier in MQWs and the AlGaN EBL to enhance the hole injection. The optical output power at 20 mA of LEDs with interlayer is increased by 20% more than that of LEDs without an interlayer. This improvement is attributed to the enhanced radiative recombination rate, which is due to a more uniform hole distribution and higher hole concentration in MQWs.

Keywords

III-V semiconductors; aluminium compounds; electron-hole recombination; gallium compounds; indium compounds; light emitting diodes; quantum well devices; wide band gap semiconductors; AlGaN; InGaN-GaN; band diagram; barrier layer; electron blocking layer; enhanced optical power; enhanced radiative recombination; hole barrier height reduction; hole concentration; light emitting diode; multiple quantum wells; uniform hole distribution; Aluminum gallium nitride; Charge carrier processes; Electron optics; Gallium nitride; Light emitting diodes; Power generation; Quantum well devices; AlGaN interlayer; InGaN; electron blocking layer (EBL); light-emitting diodes (LEDs);

fLanguage

English

Journal_Title

Photonics Technology Letters, IEEE

Publisher

ieee

ISSN

1041-1135

Type

jour

DOI

10.1109/LPT.2012.2217125

Filename

6311423