Investigation of GaN-based light emitting diodes with nano-hole patterned sapphire substrate (NHPSS) by nano-imprint lithography

Huang, H. W.; Lin, Chien-Chung; Huang, Jen-Wei; Lee, K. Y.; Lin, Chia−Feng; Yu, C. C.; Tsai, J. Y.; Hsueh, Ruey-Lue Wang; Kuo, Hao‐Chung; Wang, S. C.

doi:10.1016/j.mseb.2009.07.006

Cited by 43 publications

(29 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…18 Therefore, nanoscale air voids are typically formed between patterns. Numerous reports 1, [19][20][21][22] indicate that the air voids at the GaN/NPSS interface help to enhance the LEE of conventional face-up LEDs. This is because the air voids can increase the possibility of optical reflection and scattering arising from the larger difference in refractive index between the epitaxial GaN film (n GaN =2.4) and air (n air =1) than that between GaN and sapphire (n sap =1.7).…”

Section: Introductionmentioning

confidence: 99%

Improved light extraction efficiency of GaN-based flip-chip light-emitting diodes with an antireflective interface layer

Dongxue

Liu

et al. 2016

AIP Advances

View full text Add to dashboard Cite

GaN-based flip-chip light-emitting diodes (FC-LEDs) grown on nanopatterned sapphire substrates (NPSS) are fabricated using self-assembled SiO2 nanospheres as masks during inductively coupled plasma etching. By controlling the pattern spacing, epitaxial GaN can be grown from the top or bottom of patterns to obtain two different GaN/substrate interfaces. The optoelectronic characteristics of FC-LED chips with different GaN/sapphire interfaces are studied. The FC-LED with an antireflective interface layer consisting of a NPSS with GaN in the pattern spacings demonstrates better optical properties than the FC-LED with an interface embedded with air voids. Our study indicates that the two types of FC-LEDs grown on NPSS show higher crystal quality and improved electrical and optical characteristics compared with those of FC-LEDs grown on conventional planar sapphire substrates.

show abstract

Section: Introductionmentioning

confidence: 99%

Improved light extraction efficiency of GaN-based flip-chip light-emitting diodes with an antireflective interface layer

Dongxue

Liu

et al. 2016

AIP Advances

View full text Add to dashboard Cite

show abstract

“…[9][10][11] Fabrication process flow is shown in Fig 7. First, the patterning of the sapphire substrate was carried out by NIL process using Si mold. The sapphire substrate was then dry etched using inductively coupled plasma (ICP) etching machine.…”

Section: Nanoimprint Lithographymentioning

confidence: 99%

Improving light-emitting diode performance through sapphire substrate double-side patterning

et al. 2013

View full text Add to dashboard Cite

Abstract. Here, we present a new double-side patterned sapphire substrate methodology that improves the efficiency of gallium nitride-light emitting diodes (GaN-LEDs). The light extraction efficiency of GaNbased LEDs was analyzed through the use of a ray-tracing simulation. The extraction efficiency was simulated using patterned sapphire substrate LEDs with a variety of shapes, depths, sizes, and spacing. Through the optimal patterning of the various factors, high extraction efficiency was realized and subsequently improved upon. The thermal LED characteristics were analyzed through the use of the COMSOL general heat transfer module. The LEDs patterned on the sapphire substrate were fabricated using nano imprint lithography. We found that the output power of the double-side patterned LED was 52% greater than that of a flat LED. The thermal resistance of the double side patterned LED was 9.5 K∕W less than that found for the flat LED. © The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

show abstract

“…If the size of the PSS structures is in nanoscales, the required buffer layer is thin and may be achieved by the side growth of the epitaxial layer, streamlining the LED growth process and increasing the process yield. Huang et al [58] created polymer nanostructures on the sapphire substrate using the thermal pressing technique. The imprint material also acted as the resist layer for the ICP etching process.…”

Section: The Effects Of Npssmentioning

confidence: 99%

Improving the Light-Emitting Efficiency of GaN LEDs Using Nanoimprint Lithography

Lee¹,

Tu²

2011

Recent Advances in Nanofabrication Techniques and Applications

View full text Add to dashboard Cite

Investigation of GaN-based light emitting diodes with nano-hole patterned sapphire substrate (NHPSS) by nano-imprint lithography

Cited by 43 publications

References 13 publications

Improved light extraction efficiency of GaN-based flip-chip light-emitting diodes with an antireflective interface layer

Improved light extraction efficiency of GaN-based flip-chip light-emitting diodes with an antireflective interface layer

Improving light-emitting diode performance through sapphire substrate double-side patterning

Improving the Light-Emitting Efficiency of GaN LEDs Using Nanoimprint Lithography

Contact Info

Product

Resources

About