Study of GaN LED ITO Nano-Gratings With Standing Wave Analysis

Author

Halpin, Gabriel ; Robinson, Travis ; Xiaomin Jin ; Xiang-Ning Kang ; Guo-Ying Zhang

Author_Institution

Electr. Eng. Dept., California Polytech. State Univ., San Luis Obispo, AZ, USA

Volume

6

Issue

3

fYear

2014

fDate

Jun-14

Firstpage

1

Lastpage

10

Abstract

This study reveals the effect of nanoscale ITO transmission gratings on light emission from the top, sides, and bottom of a GaN light-emitting diode (LED), based on the substrate standing wave analysis. First, we show that sapphire substrate thickness affects the standing wave pattern in the LED and find the best- and worst-case sapphire thicknesses. Second, we find that adding nanoscale ITO transmission gratings can improve light extraction by 222% or 253%, depending on the reference chosen. Third, we observe that maximizing top light emission with the nano-grating can significantly reduce bottom and side light emissions. Finally, we study grating performance over different wavelengths and generate the LED spectrum.

Keywords

III-V semiconductors; diffraction gratings; gallium compounds; indium compounds; light emitting diodes; nanophotonics; sapphire; wide band gap semiconductors; Al₂O₃; GaN; GaN LED ITO nanogratings; ITO; light emission; light extraction; light-emitting diode; nanoscale ITO transmission gratings; sapphire thicknesses; substrate standing wave analysis; Finite difference methods; Gallium nitride; Gratings; Indium tin oxide; Light emitting diodes; Substrates; Time-domain analysis; GaN; Grating; LED; nano-scale;

fLanguage

English

Journal_Title

Photonics Journal, IEEE

Publisher

ieee

ISSN

1943-0655

Type

jour

DOI

10.1109/JPHOT.2014.2323296

Filename

6814847