High optical power and low-efficiency droop blue light-emitting diodes using compositionally step-graded InGaN barrier

Author

Chih-Chien Pan ; Qimin Yan ; Houqiang Fu ; Yuji Zhao ; Yuh-Renn Wu ; Van de Walle, Chris ; Nakamura, Shuji ; DenBaars, Steven P.

Author_Institution

Mater. Dept., Univ. of California, Santa Barbara, Santa Barbara, CA, USA

Volume

51

Issue

15

fYear

2015

fDate

7 23 2015

Firstpage

1187

Lastpage

1189

Abstract

A compositionally step-graded (CSG) InGaN barrier is designed for the active region of c-plane blue light-emitting diodes (LEDs). High external quantum efficiencies of 45, 42, 39 and 36% are achieved at current densities of 100, 200, 300 and 400 A/cm², respectively. Compared with GaN barrier devices, LEDs with CSG InGaN barriers showed higher power, lower operating voltage and smaller wavelength blueshift, compared with GaN barrier LEDs. Owing to the low-voltage performance, higher wall-plug efficiency can be achieved for blue LEDs with CSG InGaN barriers.

Keywords

III-V semiconductors; gallium compounds; indium compounds; light emitting diodes; wide band gap semiconductors; CSG; InGaN; LEDs; WPE; c-plane blue light-emitting diodes; compositionally step-graded barrier; efficiency 36 percent; efficiency 39 percent; efficiency 42 percent; efficiency 45 percent; high optical power light-emitting diodes; low-efficiency droop blue light-emitting diodes; low-voltage performance; wall-plug efficiency;

fLanguage

English

Journal_Title

Electronics Letters

Publisher

iet

ISSN

0013-5194

Type

jour

DOI

10.1049/el.2015.1647

Filename

7163422