Light-extraction enhancement in GaN-based light-emitting diodes using grade-refractive-index amorphous titanium oxide films with porous structures

Liu, Day-Shan; Lin, Tan-Wei; Huang, Bing-Wen; Juang, Fuh-Shyang; Lei, Po-Hsun; Hu, Chen-Ze
April 2009
Applied Physics Letters;4/6/2009, Vol. 94 Issue 14, p143502
Academic Journal
Amorphous titanium oxide (a-TiOx:OH) films prepared by plasma-enhanced chemical-vapor deposition at 200 and 25 °C are in turn deposited onto the GaN-based light-emitting diode (LED) to enhance the associated light extraction efficiency. The refractive index, porosity, and photocatalytic effect of the deposited films are correlated strongly with the deposition temperatures. The efficiency is enhanced by a factor of ∼1.31 over that of the uncoated LEDs and exhibited an excellent photocatalytic property after an external UV light irradiation. The increase in the light extraction is related to the reduction in the Fresnel transmission loss and the enhancement of the light scattering into the escape cone by using the graded-refractive-index a-TiOx:OH film with porous structures.


Related Articles

  • Nanoepitaxy to improve the efficiency of InGaN light-emitting diodes. Zang, K. Y.; Chua, S. J.; Teng, J. H.; Ang, N. S. S.; Yong, A. M.; Chow, S. Y. // Applied Physics Letters;6/16/2008, Vol. 92 Issue 24, p243126 

    InGaN/GaN blue light-emitting diode (LED) structures are grown on nanoepitaxial lateral overgrown (NELO) GaN template on sapphire substrates by metal organic chemical vapor deposition. Nanopore arrays in SiO2 film are fabricated on the underlying GaN using anodic alumina as etch masks, resulting...

  • First room-temperature cw operation of a GaInAsP/InP light-emitting diode on a silicon substrate. Razeghi, M.; Blondeau, R.; Defour, M.; Omnes, F.; Maurel, P.; Brillouet, F. // Applied Physics Letters;9/5/1988, Vol. 53 Issue 10, p854 

    We report in this letter the first successful fabrication of an InP-GaInAsP light-emitting diode, emitting at 1.15 μm grown by low-pressure metalorganic chemical vapor deposition on a silicon substrate. The device has been operated under continuous wave operation at room temperature for 24 h...

  • Optical degradation of InGaN/AlGaN light-emitting diode on sapphire substrate grown by metalorganic chemical vapor deposition. Egawa, T.; Ishikawa, H.; Jimbo, T.; Umeno, M. // Applied Physics Letters;8/5/1996, Vol. 69 Issue 6, p830 

    We report an optical degradation of an InGaN/AlGaN double-heterostructure light-emitting diode (LED) on a sapphire substrate grown by metalorgonic chemical vapor deposition. Electroluminescence, electron-beam induced current, and cathodoluminescence observations have shown that the degraded...

  • Pressure dependence of AlxGa1-xAs light emitting diodes near the direct-indirect transition. Kaliski, R. W.; Epler, J. E.; Holonyak, N.; Peanasky, M. J.; Herrmannsfeldt, G. A.; Drickamer, H. G.; Tsai, M. J.; Camras, M. D.; Kellert, F. G.; Wu, C. H.; Craford, M. G. // Journal of Applied Physics;3/1/1985, Vol. 57 Issue 5, p1734 

    Presents a study that examined Al[subx]Ga[sub1-x]As double heterostructure light emitting diodes (LED) grown by liquid phase epitaxy. Behavior of LED fabricated from a crystal grown by metalorganic chemical vapor deposition; Effect of residual defects and competing nonradiative recombination;...

  • High-brightness InGaN/AlGaN double-heterostructure blue-green-light-emitting diodes. Nakamura, Shuji; Mukai, Takashi; Senoh, Masayuki // Journal of Applied Physics;12/15/1994, Vol. 76 Issue 12, p8189 

    Presents information on a study which fabricated high-brightness InGaN/AlGaN double-heterostructure blue-green-light-emitting diodes. Discussion of the room-temperature Hall and photoluminescence measurements performed on InGaN films grown on GaN films; Electroluminescence spectra; Growth of...

  • Fabrication and characterization of n-ZnO/p-AlGaN heterojunction light-emitting diodes on 6H-SiC substrates. Alivov, Ya. I.; Kalinina, E. V.; Cherenkov, A. E.; Look, D. C.; Ataev, B. M.; Omaev, A. K.; Chukichev, M. V.; Bagnall, D. M. // Applied Physics Letters;12/8/2003, Vol. 83 Issue 23, p4719 

    We report on the fabrication of n-ZnO/p-AlGaN heterojunction light-emitting diodes on 6H-SiC substrates. Hydride vapor phase epitaxy was used to grow p-type AlGaN, while chemical vapor deposition was used to produce the n-type ZnO layers. Diode-like, rectifying I–V characteristics, with...

  • Light-emitting diodes and laser diodes based on a Ga[sub 1-x]In[sub x]As/GaAs[sub 1-y]Sb[sub y]... Peter, M.; Kiefer, R.; Fuchs, F.; Herres, N.; Winkler, K.; Bachem, K.-H.; Wagner, J. // Applied Physics Letters;4/5/1999, Vol. 74 Issue 14, p1951 

    Reports on the fabrication and characterization of light-emitting diodes and laser diodes with a staggered type II Ga[sub 1-x]In[sub x]As/GaAs[1-y]Sb[sub y] superlattice (SL) as the active region. Growth of SL strain compensated on the InP substrate using metalorganic chemical vapor deposition;...

  • Demonstration of an InGaN-based light-emitting diode on an AlN/sapphire template by metalorganic chemical vapor deposition. Egawa, T.; Ohmura, H.; Ishikawa, H.; Jimbo, T. // Applied Physics Letters;7/8/2002, Vol. 81 Issue 2, p292 

    Structural, electrical, and optical properties of an InGaN-based light-emitting diode (LED) on an A1N/sapphire template have been studied and compared with the conventional LED properties on a sapphire substrate. In comparison to the LED on sapphire, the LED on A1N/sapphire template has shown...

  • Atom-by-atom simulations of chemical vapor deposition of nanoporous hydrogenated silicon nitride. Houska, J.; Klemberg-Sapieha, J. E.; Martinu, L. // Journal of Applied Physics;Apr2010, Vol. 107 Issue 8, p083501 

    Amorphous hydrogenated silicon nitride (SiNH) materials prepared by plasma-enhanced chemical vapor deposition (PECVD) are of high interest because of their suitability for diverse applications including optical coatings, gas/vapor permeation barriers, corrosion resistant, and protective coatings...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics