Improved Light Extraction Efficiency by Photonic Crystal Arrays on Transparent Contact Layer Using Focused Ion Beams

• Authors: G. Wu , B. Tsai , S. Kung , C. Wu
• Languages of publication: EN

Abstracts

EN

Nitride-based thin-film materials have become increasingly important for the high brightness light-emitting diode applications. The improvements in light extraction and lower power consumption are highly desired. Although the internal quantum efficiency of GaN-based LED has been relatively high, only a small fraction of light can be extracted. In this study, a new design of two-dimensional photonic crystal array has been prepared on the top transparent contact layer of indium-tin oxide film to improve the light extraction efficiency using focused ion beam. The acceleration voltage of the Ga dual-beam nanotechnology system SMI 3050 was 30 kV and the ion beam current was 100 pA. The cylindrical air holes had the diameter of 150 nm and depth of 100 nm. The micro photoluminescence analysis results showed that the light output intensity could be 1.5 times of that of the non-patterned control sample. In addition, the structural damage from the focused ion beam drilling of GaN step could be eliminated. The excellent I-V characteristics have been maintained, and the external light extraction efficiency would be still improved for the LED devices.

Keywords

EN

81.16.Rf; 42.70.Qs; 41.75.Ak

Discipline

• 42.70.Qs: Photonic bandgap materials(for photonic crystal lasers, see 42.55.Tv)
• 81.16.Rf: Micro- and nanoscale pattern formation
• 41.75.Ak: Positive-ion beams

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 2011
• Volume: 120
• Issue: 1
• Pages: 140-143

Dates

published

2011-07

Contributors

author

G. Wu

• Institute of Electro-Optical Engineering, Chang Gung University, Kweisan, Taoyuan 333, Taiwan R.O.C.

author

B. Tsai

• Institute of Electro-Optical Engineering, Chang Gung University, Kweisan, Taoyuan 333, Taiwan R.O.C.

author

S. Kung

• Department of Dentistry, Chang Gung Medical Center, Kweisan, Taoyuan 333, Taiwan R.O.C.

author

C. Wu

• Department of Applied Mathematics, National Dong Hwa University, Hualien 974, Taiwan R.O.C.

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Identifiers

DOI

10.12693/APhysPolA.120.140