Improvement of light extraction efficiency of flip-chip light-emitting diode by texturing the bottom side surface of sapphire substrate

Author

Dae-Seob Han ; Ja-Yeon Kim ; Seok-In Na ; Sang-Hoon Kim ; Ki-Dong Lee ; Bongjin Kim ; Seong-Ju Park

Author_Institution

Dept. of Mater. Sci. & Eng., Gwangju Inst. of Sci. & Technol.

Volume

18

Issue

13

fYear

2006

fDate

7/1/2006 12:00:00 AM

Firstpage

1406

Lastpage

1408

Abstract

A high light-extraction efficiency was demonstrated in the flip-chip light-emitting diode (FCLED) with a textured sapphire substrate. The bottom side of a sapphire substrate was patterned using a dry etching process to increase the light-extraction efficiency. Light output power measurements indicated that the scattering of photons emitted in the active layer was considerably enhanced at the textured sapphire substrate resulting in an increase in the probability of escaping from the FCLED. The light-output power of the FCLED was increased by 40.2% for a 0.4-mum deep FCLED with a periodic distance of 13-mum mesh-type texture on the bottom side of the sapphire substrate

Keywords

etching; flip-chip devices; light emitting diodes; light scattering; Al₂O₃; bottom side surface; dry etching; flip-chip light-emitting diode; light extraction efficiency; light output power measurements; mesh-type texture; photon scattering; sapphire substrate; Dry etching; Gallium nitride; LED lamps; Laboratories; Light emitting diodes; Materials science and technology; Plasma displays; Power generation; Substrates; Surface texture; Dry etching; GaN; extraction efficiency; inductively coupled plasma (ICP); light-emitting diodes (LEDs); light-output power; sapphire etching;

fLanguage

English

Journal_Title

Photonics Technology Letters, IEEE

Publisher

ieee

ISSN

1041-1135

Type

jour

DOI

10.1109/LPT.2006.877565

Filename

1643238