Enhancement of Light Extraction Efficiency of InGa Quantum Wells Light-Emitting Diodes with Polydimethylsiloxane Concave Microstructures

被引：2

作者：

Ee, Yik-Khoon ^{[1
]}

Kumnorkaew, Pisist ^{[2
]}

Tong, Hua ^{[1
]}

Arif, Ronald A. ^{[1
]}

Gilchrist, James F. ^{[2
]}

Tansu, Nelson ^{[1
]}

机构：

[1] Lehigh Univ, Dept Elect & Comp Engn, Ctr Opt Technol, Bethlehem, PA 18015 USA

[2] Lehigh Univ, Ctr Adv Mat & Nanotechnol, Dept Chem Engn, Bethlehem, PA 18015 USA

来源：

LIGHT-EMITTING DIODES: MATERIALS, DEVICES, AND APPLICATIONS FOR SOLID STATE LIGHTING XIII | 2009年 / 7231卷

基金：

美国国家科学基金会;

关键词：

InGaN quantum wells; light emitting diodes; light extraction efficiency; concave microstructures; colloid; REFRACTIVE-INDEX; DEPOSITION; OUTPUT;

D O I：

10.1117/12.808600

中图分类号：

TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

Improvement of light extraction efficiency of InGaN light emitting diodes (LEDs) using polydimethylsiloxane (PDMS) concave microstructures arrays was demonstrated. The size effect of the concave microstructures on the light extraction efficiency of III-Nitride LEDs was studied. Depending on the size of the concave microsturctures, ray tracing simulations show that the use of PDMS concave microstructures arrays can lead to increase in light extraction efficiency of InGaN LEDs by 1.4 to 1.9 times. Experiments utilizing 1.0 mu m PDMS concave microstructures arrays demonstrated 1.60 times improvement in light extraction, which is consistent with simulated improvement of 1.63 times. The enhancement in light extraction efficiency is attributed to increase in effective photon escape cone due to PDMS concave microstructures arrays, and reduced Fresnel reflection within the photon escape cone due to the grading of refractive index change between GaN / PDMS / air interface.

引用

页数：7

共 19 条

[1] GaN micro-light-emitting diode arrays with monolithically integrated sapphire microlenses [J].

Choi, HW ;

Liu, C ;

Gu, E ;

McConnell, G ;

Girkin, JM ;

Watson, IM ;

Dawson, MD .

APPLIED PHYSICS LETTERS, 2004, 84 (13) :2253-2255

[2] Enhancement of light extraction efficiency of InGaN quantum wells light emitting diodes using SiO2/polystyrene microlens arrays [J].

Ee, Yik-Khoon ;

Arif, Ronald A. ;

Tansu, Nelson ;

Kumnorkaew, Pisist ;

Gilchrist, James F. .

APPLIED PHYSICS LETTERS, 2007, 91 (22)

[3]

FISCHER AJ, 2007, P C LAS EL BALT MD C

[4] Increase in the extraction efficiency of GaN-based light-emitting diodes via surface roughening [J].

Fujii, T ;

Gao, Y ;

Sharma, R ;

Hu, EL ;

DenBaars, SP ;

Nakamura, S .

APPLIED PHYSICS LETTERS, 2004, 84 (06) :855-857

[5] Improved light-output and electrical performance of InGaN-based, light-emitting diode by microroughening of the p-GaN surface [J].

Huh, C ;

Lee, KS ;

Kang, EJ ;

Park, SJ .

JOURNAL OF APPLIED PHYSICS, 2003, 93 (11) :9383-9385

[6]

KIM JK, 2007, P C LAS EL BALT MD C

[7] Enhancement in external quantum efficiency of blue light-emitting diode by photonic crystal surface grating [J].

Kim, T ;

Danner, AJ ;

Choquette, KD .

ELECTRONICS LETTERS, 2005, 41 (20) :1138-1139

[8] Development of high efficiency GaN-based multiquantum-well light-emitting diodes and their applications [J].

Koike, M ;

Shibata, N ;

Kato, H ;

Takahashi, Y .

IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS, 2002, 8 (02) :271-277

[9] Investigation of the Deposition of Microsphere Monolayers for Fabrication of Microlens Arrays [J].

Kumnorkaew, Pisist ;

Ee, Yik-Khoon ;

Tansu, Nelson ;

Gilchrist, James F. .

LANGMUIR, 2008, 24 (21) :12150-12157

[10] Fabrication of reflective GaN mesa sidewalls for the application to high extraction efficiency LEDs [J].

Lee, Jae-Soong ;

Lee, Joonhee ;

Kim, Sunghwan ;

Jeon, Heonsu .

PHYSICA STATUS SOLIDI C - CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 4 NO 7 2007, 2007, 4 (07) :2625-+

← 1 2 →