Abstract

GaN-based light-emitting diode (LED) was fabricated on the sapphire substrate with monolithic convex microstructures (CMs) array. Using confocal scanning electroluminescence (EL), we have directly observed the strong outcoupling phenomenon of the light confined in a LED via the CMs array. This outcoupled light could be efficiently converged on the convex center through consecutive reflections at the flat area and the curved slant area of the CMs array. Compared to the conventional LED, the ray tracing simulation and far field EL results of the LED with a CM array showed efficient light extraction toward the top surface, i.e., 0-5, 40-45 and 60-65 degree by the outcoupling effect. We conclude that the outcoupled optical path via CMs is the dominant factor of the enhanced light extraction in the LED with a CM array.

© 2011 OSA

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  1. S. Nakamura, “Current status of GaN-based solid state lighting,” MRS Bull. 34(02), 101–107 (2009).
    [CrossRef]
  2. J. J. Wierer, M. R. Krames, J. E. Epler, N. F. Gardner, M. G. Craford, J. R. Wendt, J. A. Simmons, and M. M. Sigalas, “InGaN/GaN quantum-well heterostructures light-emitting diodes employing photonic crystal structures,” Appl. Phys. Lett. 84(19), 3885 (2004).
    [CrossRef]
  3. Z. Liliental-Weber and D. Cherns, “Microstructure of lateral overgrown GaN layers,” J. Appl. Phys. 89(12), 7833–7840 (2001).
    [CrossRef]
  4. J.-F. Carlin, C. Zellweger, J. Dorsaz, S. Nicolay, G. Christmann, E. Feltin, R. Butté, and N. Grandjean, “Progresses in III-nitride distributed Bragg reflectors and microcavities using AlInN/GaN materials,” Phys. Status Solidi 242(11), 2326–2344 (2005) (b).
    [CrossRef]
  5. J. K. Kim, A. N. Noemaun, F. W. Mont, D. Meyaard, E. F. Schubert, D. J. Poxson, H. Kim, C. Sone, and Y. Park, “Elimination of total internal reflection in GaInN light-emitting diodes by graded-refractive-index micropillars,” Appl. Phys. Lett. 93(22), 221111 (2008).
    [CrossRef]
  6. T. S. Oh, H. Jeong, Y. S. Lee, J. D. Kim, T. H. Seo, H. Kim, A. H. Park, K. J. Lee, and E.-K. Suh, “Coupling of InGaN/GaN multiquantum-wells photoluminescence to surface plasmons in platinum nanocluster,” Appl. Phys. Lett. 95(11), 111112 (2009).
    [CrossRef]
  7. T. V. Cuong, H. S. Cheong, H. G. Kim, H. Y. Kim, C.-H. Hong, E. K. Suh, H. K. Cho, and B. H. Kong, “enhanced light output from aligned micropit InGaN-based light emitting diodes using wet-etch sapphire patterning,” Appl. Phys. Lett. 90(13), 131107 (2007).
    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
  15. T. S. Oh, H. Jeong, Y. S. Lee, T. H. Seo, A. H. Park, H. Kim, K. J. Lee, M. S. Jeong, and E.-K. Suh, “Defect structure originating from threading dislocations within the GaN film grown on a convex patterned sapphire substrate,” Thin Solid Films 519(8), 2398–2401 (2011).
    [CrossRef]
  16. G. A. Onushkin, S.-S. Hong, J.-H. Lee, J.-S. Park, J.-K. Son, M.-H. Kim, and Y. J. Park, “Local electroluminescence and time-resolved photoluminescence study of InGaN light-emitting diodes,” Appl. Phys. Lett. 95(10), 101904 (2009).
    [CrossRef]

2011

T. S. Oh, H. Jeong, Y. S. Lee, T. H. Seo, A. H. Park, H. Kim, K. J. Lee, M. S. Jeong, and E.-K. Suh, “Defect structure originating from threading dislocations within the GaN film grown on a convex patterned sapphire substrate,” Thin Solid Films 519(8), 2398–2401 (2011).
[CrossRef]

2009

G. A. Onushkin, S.-S. Hong, J.-H. Lee, J.-S. Park, J.-K. Son, M.-H. Kim, and Y. J. Park, “Local electroluminescence and time-resolved photoluminescence study of InGaN light-emitting diodes,” Appl. Phys. Lett. 95(10), 101904 (2009).
[CrossRef]

T. S. Oh, H. Jeong, Y. S. Lee, J. D. Kim, T. H. Seo, H. Kim, A. H. Park, K. J. Lee, and E.-K. Suh, “Coupling of InGaN/GaN multiquantum-wells photoluminescence to surface plasmons in platinum nanocluster,” Appl. Phys. Lett. 95(11), 111112 (2009).
[CrossRef]

S. Nakamura, “Current status of GaN-based solid state lighting,” MRS Bull. 34(02), 101–107 (2009).
[CrossRef]

D.-H. Jang, J.-I. Shim, and K. Y. Yoo, “Theoretical analysis on the light extraction efficiency of GaN-based light-emitting diodes by using the ray tracing method,” J. Korean Phys. Soc. 54(6), 2373–2377 (2009).
[CrossRef]

H.-Y. Shin, S. K. Kwon, Y. I. Chang, M. J. Cho, and K. H. Park, “Reducing dislocation density in GaN films using a cone-shaped patterned sapphire substrate,” J. Cryst. Growth 311(17), 4167–4170 (2009).
[CrossRef]

C.-T. Chang, S.-K. Hsiao, E. Y. Chang, Y.-L. Hsiao, C.-Y. Lu, H.-C. Chang, K.-W. Cheng, and C.-T. Lee, “460-nm InGaN-based LEDs grown on fully inclined hemisphere-shape-patterned sapphire substrate with submicrometer spacing,” IEEE Photon. Technol. Lett. 21(19), 1366–1368 (2009).
[CrossRef]

2008

T. S. Oh, S. H. Kim, T. K. Kim, Y. S. Lee, H. Jeong, G. M. Yang, and E.-K. Suh, “GaN-based light-emitting diodes on micro-lens patterned sapphire substrate,” Jpn. J. Appl. Phys. 47(7), 5333–5336 (2008).
[CrossRef]

J. K. Kim, A. N. Noemaun, F. W. Mont, D. Meyaard, E. F. Schubert, D. J. Poxson, H. Kim, C. Sone, and Y. Park, “Elimination of total internal reflection in GaInN light-emitting diodes by graded-refractive-index micropillars,” Appl. Phys. Lett. 93(22), 221111 (2008).
[CrossRef]

2007

T. V. Cuong, H. S. Cheong, H. G. Kim, H. Y. Kim, C.-H. Hong, E. K. Suh, H. K. Cho, and B. H. Kong, “enhanced light output from aligned micropit InGaN-based light emitting diodes using wet-etch sapphire patterning,” Appl. Phys. Lett. 90(13), 131107 (2007).
[CrossRef]

2005

J.-F. Carlin, C. Zellweger, J. Dorsaz, S. Nicolay, G. Christmann, E. Feltin, R. Butté, and N. Grandjean, “Progresses in III-nitride distributed Bragg reflectors and microcavities using AlInN/GaN materials,” Phys. Status Solidi 242(11), 2326–2344 (2005) (b).
[CrossRef]

2004

J. J. Wierer, M. R. Krames, J. E. Epler, N. F. Gardner, M. G. Craford, J. R. Wendt, J. A. Simmons, and M. M. Sigalas, “InGaN/GaN quantum-well heterostructures light-emitting diodes employing photonic crystal structures,” Appl. Phys. Lett. 84(19), 3885 (2004).
[CrossRef]

Y. Nakano, O. Fujishima, and T. Kachi, “Effect of p-type activation ambient on acceptor levels in Mg-doped GaN,” J. Appl. Phys. 96(1), 415–419 (2004).
[CrossRef]

2002

M. Yamada, T. Mitani, Y. Narukawa, S. Shioji, I. Niki, S. Sonobe, K. Deguchi, M. Sano, and T. Mukai, “InGaN-based near-ultraviolet and blue-light-emitting diodes with high external quantum efficiency using a patterned sapphire substrate,” Jpn. J. Appl. Phys. 41(12B), L1431–L1433 (2002).
[CrossRef]

2001

Butté, R.

J.-F. Carlin, C. Zellweger, J. Dorsaz, S. Nicolay, G. Christmann, E. Feltin, R. Butté, and N. Grandjean, “Progresses in III-nitride distributed Bragg reflectors and microcavities using AlInN/GaN materials,” Phys. Status Solidi 242(11), 2326–2344 (2005) (b).
[CrossRef]

Carlin, J.-F.

J.-F. Carlin, C. Zellweger, J. Dorsaz, S. Nicolay, G. Christmann, E. Feltin, R. Butté, and N. Grandjean, “Progresses in III-nitride distributed Bragg reflectors and microcavities using AlInN/GaN materials,” Phys. Status Solidi 242(11), 2326–2344 (2005) (b).
[CrossRef]

Chang, C.-T.

C.-T. Chang, S.-K. Hsiao, E. Y. Chang, Y.-L. Hsiao, C.-Y. Lu, H.-C. Chang, K.-W. Cheng, and C.-T. Lee, “460-nm InGaN-based LEDs grown on fully inclined hemisphere-shape-patterned sapphire substrate with submicrometer spacing,” IEEE Photon. Technol. Lett. 21(19), 1366–1368 (2009).
[CrossRef]

Chang, E. Y.

C.-T. Chang, S.-K. Hsiao, E. Y. Chang, Y.-L. Hsiao, C.-Y. Lu, H.-C. Chang, K.-W. Cheng, and C.-T. Lee, “460-nm InGaN-based LEDs grown on fully inclined hemisphere-shape-patterned sapphire substrate with submicrometer spacing,” IEEE Photon. Technol. Lett. 21(19), 1366–1368 (2009).
[CrossRef]

Chang, H.-C.

C.-T. Chang, S.-K. Hsiao, E. Y. Chang, Y.-L. Hsiao, C.-Y. Lu, H.-C. Chang, K.-W. Cheng, and C.-T. Lee, “460-nm InGaN-based LEDs grown on fully inclined hemisphere-shape-patterned sapphire substrate with submicrometer spacing,” IEEE Photon. Technol. Lett. 21(19), 1366–1368 (2009).
[CrossRef]

Chang, Y. I.

H.-Y. Shin, S. K. Kwon, Y. I. Chang, M. J. Cho, and K. H. Park, “Reducing dislocation density in GaN films using a cone-shaped patterned sapphire substrate,” J. Cryst. Growth 311(17), 4167–4170 (2009).
[CrossRef]

Cheng, K.-W.

C.-T. Chang, S.-K. Hsiao, E. Y. Chang, Y.-L. Hsiao, C.-Y. Lu, H.-C. Chang, K.-W. Cheng, and C.-T. Lee, “460-nm InGaN-based LEDs grown on fully inclined hemisphere-shape-patterned sapphire substrate with submicrometer spacing,” IEEE Photon. Technol. Lett. 21(19), 1366–1368 (2009).
[CrossRef]

Cheong, H. S.

T. V. Cuong, H. S. Cheong, H. G. Kim, H. Y. Kim, C.-H. Hong, E. K. Suh, H. K. Cho, and B. H. Kong, “enhanced light output from aligned micropit InGaN-based light emitting diodes using wet-etch sapphire patterning,” Appl. Phys. Lett. 90(13), 131107 (2007).
[CrossRef]

Cherns, D.

Z. Liliental-Weber and D. Cherns, “Microstructure of lateral overgrown GaN layers,” J. Appl. Phys. 89(12), 7833–7840 (2001).
[CrossRef]

Cho, H. K.

T. V. Cuong, H. S. Cheong, H. G. Kim, H. Y. Kim, C.-H. Hong, E. K. Suh, H. K. Cho, and B. H. Kong, “enhanced light output from aligned micropit InGaN-based light emitting diodes using wet-etch sapphire patterning,” Appl. Phys. Lett. 90(13), 131107 (2007).
[CrossRef]

Cho, M. J.

H.-Y. Shin, S. K. Kwon, Y. I. Chang, M. J. Cho, and K. H. Park, “Reducing dislocation density in GaN films using a cone-shaped patterned sapphire substrate,” J. Cryst. Growth 311(17), 4167–4170 (2009).
[CrossRef]

Christmann, G.

J.-F. Carlin, C. Zellweger, J. Dorsaz, S. Nicolay, G. Christmann, E. Feltin, R. Butté, and N. Grandjean, “Progresses in III-nitride distributed Bragg reflectors and microcavities using AlInN/GaN materials,” Phys. Status Solidi 242(11), 2326–2344 (2005) (b).
[CrossRef]

Craford, M. G.

J. J. Wierer, M. R. Krames, J. E. Epler, N. F. Gardner, M. G. Craford, J. R. Wendt, J. A. Simmons, and M. M. Sigalas, “InGaN/GaN quantum-well heterostructures light-emitting diodes employing photonic crystal structures,” Appl. Phys. Lett. 84(19), 3885 (2004).
[CrossRef]

Cuong, T. V.

T. V. Cuong, H. S. Cheong, H. G. Kim, H. Y. Kim, C.-H. Hong, E. K. Suh, H. K. Cho, and B. H. Kong, “enhanced light output from aligned micropit InGaN-based light emitting diodes using wet-etch sapphire patterning,” Appl. Phys. Lett. 90(13), 131107 (2007).
[CrossRef]

Deguchi, K.

M. Yamada, T. Mitani, Y. Narukawa, S. Shioji, I. Niki, S. Sonobe, K. Deguchi, M. Sano, and T. Mukai, “InGaN-based near-ultraviolet and blue-light-emitting diodes with high external quantum efficiency using a patterned sapphire substrate,” Jpn. J. Appl. Phys. 41(12B), L1431–L1433 (2002).
[CrossRef]

Dorsaz, J.

J.-F. Carlin, C. Zellweger, J. Dorsaz, S. Nicolay, G. Christmann, E. Feltin, R. Butté, and N. Grandjean, “Progresses in III-nitride distributed Bragg reflectors and microcavities using AlInN/GaN materials,” Phys. Status Solidi 242(11), 2326–2344 (2005) (b).
[CrossRef]

Epler, J. E.

J. J. Wierer, M. R. Krames, J. E. Epler, N. F. Gardner, M. G. Craford, J. R. Wendt, J. A. Simmons, and M. M. Sigalas, “InGaN/GaN quantum-well heterostructures light-emitting diodes employing photonic crystal structures,” Appl. Phys. Lett. 84(19), 3885 (2004).
[CrossRef]

Feltin, E.

J.-F. Carlin, C. Zellweger, J. Dorsaz, S. Nicolay, G. Christmann, E. Feltin, R. Butté, and N. Grandjean, “Progresses in III-nitride distributed Bragg reflectors and microcavities using AlInN/GaN materials,” Phys. Status Solidi 242(11), 2326–2344 (2005) (b).
[CrossRef]

Fujishima, O.

Y. Nakano, O. Fujishima, and T. Kachi, “Effect of p-type activation ambient on acceptor levels in Mg-doped GaN,” J. Appl. Phys. 96(1), 415–419 (2004).
[CrossRef]

Gardner, N. F.

J. J. Wierer, M. R. Krames, J. E. Epler, N. F. Gardner, M. G. Craford, J. R. Wendt, J. A. Simmons, and M. M. Sigalas, “InGaN/GaN quantum-well heterostructures light-emitting diodes employing photonic crystal structures,” Appl. Phys. Lett. 84(19), 3885 (2004).
[CrossRef]

Grandjean, N.

J.-F. Carlin, C. Zellweger, J. Dorsaz, S. Nicolay, G. Christmann, E. Feltin, R. Butté, and N. Grandjean, “Progresses in III-nitride distributed Bragg reflectors and microcavities using AlInN/GaN materials,” Phys. Status Solidi 242(11), 2326–2344 (2005) (b).
[CrossRef]

Hong, C.-H.

T. V. Cuong, H. S. Cheong, H. G. Kim, H. Y. Kim, C.-H. Hong, E. K. Suh, H. K. Cho, and B. H. Kong, “enhanced light output from aligned micropit InGaN-based light emitting diodes using wet-etch sapphire patterning,” Appl. Phys. Lett. 90(13), 131107 (2007).
[CrossRef]

Hong, S.-S.

G. A. Onushkin, S.-S. Hong, J.-H. Lee, J.-S. Park, J.-K. Son, M.-H. Kim, and Y. J. Park, “Local electroluminescence and time-resolved photoluminescence study of InGaN light-emitting diodes,” Appl. Phys. Lett. 95(10), 101904 (2009).
[CrossRef]

Hsiao, S.-K.

C.-T. Chang, S.-K. Hsiao, E. Y. Chang, Y.-L. Hsiao, C.-Y. Lu, H.-C. Chang, K.-W. Cheng, and C.-T. Lee, “460-nm InGaN-based LEDs grown on fully inclined hemisphere-shape-patterned sapphire substrate with submicrometer spacing,” IEEE Photon. Technol. Lett. 21(19), 1366–1368 (2009).
[CrossRef]

Hsiao, Y.-L.

C.-T. Chang, S.-K. Hsiao, E. Y. Chang, Y.-L. Hsiao, C.-Y. Lu, H.-C. Chang, K.-W. Cheng, and C.-T. Lee, “460-nm InGaN-based LEDs grown on fully inclined hemisphere-shape-patterned sapphire substrate with submicrometer spacing,” IEEE Photon. Technol. Lett. 21(19), 1366–1368 (2009).
[CrossRef]

Jang, D.-H.

D.-H. Jang, J.-I. Shim, and K. Y. Yoo, “Theoretical analysis on the light extraction efficiency of GaN-based light-emitting diodes by using the ray tracing method,” J. Korean Phys. Soc. 54(6), 2373–2377 (2009).
[CrossRef]

Jeon, H.

Jeong, H.

T. S. Oh, H. Jeong, Y. S. Lee, T. H. Seo, A. H. Park, H. Kim, K. J. Lee, M. S. Jeong, and E.-K. Suh, “Defect structure originating from threading dislocations within the GaN film grown on a convex patterned sapphire substrate,” Thin Solid Films 519(8), 2398–2401 (2011).
[CrossRef]

T. S. Oh, H. Jeong, Y. S. Lee, J. D. Kim, T. H. Seo, H. Kim, A. H. Park, K. J. Lee, and E.-K. Suh, “Coupling of InGaN/GaN multiquantum-wells photoluminescence to surface plasmons in platinum nanocluster,” Appl. Phys. Lett. 95(11), 111112 (2009).
[CrossRef]

T. S. Oh, S. H. Kim, T. K. Kim, Y. S. Lee, H. Jeong, G. M. Yang, and E.-K. Suh, “GaN-based light-emitting diodes on micro-lens patterned sapphire substrate,” Jpn. J. Appl. Phys. 47(7), 5333–5336 (2008).
[CrossRef]

Jeong, M. S.

T. S. Oh, H. Jeong, Y. S. Lee, T. H. Seo, A. H. Park, H. Kim, K. J. Lee, M. S. Jeong, and E.-K. Suh, “Defect structure originating from threading dislocations within the GaN film grown on a convex patterned sapphire substrate,” Thin Solid Films 519(8), 2398–2401 (2011).
[CrossRef]

Kachi, T.

Y. Nakano, O. Fujishima, and T. Kachi, “Effect of p-type activation ambient on acceptor levels in Mg-doped GaN,” J. Appl. Phys. 96(1), 415–419 (2004).
[CrossRef]

Kim, H.

T. S. Oh, H. Jeong, Y. S. Lee, T. H. Seo, A. H. Park, H. Kim, K. J. Lee, M. S. Jeong, and E.-K. Suh, “Defect structure originating from threading dislocations within the GaN film grown on a convex patterned sapphire substrate,” Thin Solid Films 519(8), 2398–2401 (2011).
[CrossRef]

T. S. Oh, H. Jeong, Y. S. Lee, J. D. Kim, T. H. Seo, H. Kim, A. H. Park, K. J. Lee, and E.-K. Suh, “Coupling of InGaN/GaN multiquantum-wells photoluminescence to surface plasmons in platinum nanocluster,” Appl. Phys. Lett. 95(11), 111112 (2009).
[CrossRef]

J. K. Kim, A. N. Noemaun, F. W. Mont, D. Meyaard, E. F. Schubert, D. J. Poxson, H. Kim, C. Sone, and Y. Park, “Elimination of total internal reflection in GaInN light-emitting diodes by graded-refractive-index micropillars,” Appl. Phys. Lett. 93(22), 221111 (2008).
[CrossRef]

Kim, H. G.

T. V. Cuong, H. S. Cheong, H. G. Kim, H. Y. Kim, C.-H. Hong, E. K. Suh, H. K. Cho, and B. H. Kong, “enhanced light output from aligned micropit InGaN-based light emitting diodes using wet-etch sapphire patterning,” Appl. Phys. Lett. 90(13), 131107 (2007).
[CrossRef]

Kim, H. Y.

T. V. Cuong, H. S. Cheong, H. G. Kim, H. Y. Kim, C.-H. Hong, E. K. Suh, H. K. Cho, and B. H. Kong, “enhanced light output from aligned micropit InGaN-based light emitting diodes using wet-etch sapphire patterning,” Appl. Phys. Lett. 90(13), 131107 (2007).
[CrossRef]

Kim, J. D.

T. S. Oh, H. Jeong, Y. S. Lee, J. D. Kim, T. H. Seo, H. Kim, A. H. Park, K. J. Lee, and E.-K. Suh, “Coupling of InGaN/GaN multiquantum-wells photoluminescence to surface plasmons in platinum nanocluster,” Appl. Phys. Lett. 95(11), 111112 (2009).
[CrossRef]

Kim, J. K.

J. K. Kim, A. N. Noemaun, F. W. Mont, D. Meyaard, E. F. Schubert, D. J. Poxson, H. Kim, C. Sone, and Y. Park, “Elimination of total internal reflection in GaInN light-emitting diodes by graded-refractive-index micropillars,” Appl. Phys. Lett. 93(22), 221111 (2008).
[CrossRef]

Kim, M.-H.

G. A. Onushkin, S.-S. Hong, J.-H. Lee, J.-S. Park, J.-K. Son, M.-H. Kim, and Y. J. Park, “Local electroluminescence and time-resolved photoluminescence study of InGaN light-emitting diodes,” Appl. Phys. Lett. 95(10), 101904 (2009).
[CrossRef]

Kim, S. H.

T. S. Oh, S. H. Kim, T. K. Kim, Y. S. Lee, H. Jeong, G. M. Yang, and E.-K. Suh, “GaN-based light-emitting diodes on micro-lens patterned sapphire substrate,” Jpn. J. Appl. Phys. 47(7), 5333–5336 (2008).
[CrossRef]

Kim, T. K.

T. S. Oh, S. H. Kim, T. K. Kim, Y. S. Lee, H. Jeong, G. M. Yang, and E.-K. Suh, “GaN-based light-emitting diodes on micro-lens patterned sapphire substrate,” Jpn. J. Appl. Phys. 47(7), 5333–5336 (2008).
[CrossRef]

Kong, B. H.

T. V. Cuong, H. S. Cheong, H. G. Kim, H. Y. Kim, C.-H. Hong, E. K. Suh, H. K. Cho, and B. H. Kong, “enhanced light output from aligned micropit InGaN-based light emitting diodes using wet-etch sapphire patterning,” Appl. Phys. Lett. 90(13), 131107 (2007).
[CrossRef]

Krames, M. R.

J. J. Wierer, M. R. Krames, J. E. Epler, N. F. Gardner, M. G. Craford, J. R. Wendt, J. A. Simmons, and M. M. Sigalas, “InGaN/GaN quantum-well heterostructures light-emitting diodes employing photonic crystal structures,” Appl. Phys. Lett. 84(19), 3885 (2004).
[CrossRef]

Kwon, S. K.

H.-Y. Shin, S. K. Kwon, Y. I. Chang, M. J. Cho, and K. H. Park, “Reducing dislocation density in GaN films using a cone-shaped patterned sapphire substrate,” J. Cryst. Growth 311(17), 4167–4170 (2009).
[CrossRef]

Lee, C.-T.

C.-T. Chang, S.-K. Hsiao, E. Y. Chang, Y.-L. Hsiao, C.-Y. Lu, H.-C. Chang, K.-W. Cheng, and C.-T. Lee, “460-nm InGaN-based LEDs grown on fully inclined hemisphere-shape-patterned sapphire substrate with submicrometer spacing,” IEEE Photon. Technol. Lett. 21(19), 1366–1368 (2009).
[CrossRef]

Lee, J.-H.

G. A. Onushkin, S.-S. Hong, J.-H. Lee, J.-S. Park, J.-K. Son, M.-H. Kim, and Y. J. Park, “Local electroluminescence and time-resolved photoluminescence study of InGaN light-emitting diodes,” Appl. Phys. Lett. 95(10), 101904 (2009).
[CrossRef]

Lee, K. J.

T. S. Oh, H. Jeong, Y. S. Lee, T. H. Seo, A. H. Park, H. Kim, K. J. Lee, M. S. Jeong, and E.-K. Suh, “Defect structure originating from threading dislocations within the GaN film grown on a convex patterned sapphire substrate,” Thin Solid Films 519(8), 2398–2401 (2011).
[CrossRef]

T. S. Oh, H. Jeong, Y. S. Lee, J. D. Kim, T. H. Seo, H. Kim, A. H. Park, K. J. Lee, and E.-K. Suh, “Coupling of InGaN/GaN multiquantum-wells photoluminescence to surface plasmons in platinum nanocluster,” Appl. Phys. Lett. 95(11), 111112 (2009).
[CrossRef]

Lee, Y. S.

T. S. Oh, H. Jeong, Y. S. Lee, T. H. Seo, A. H. Park, H. Kim, K. J. Lee, M. S. Jeong, and E.-K. Suh, “Defect structure originating from threading dislocations within the GaN film grown on a convex patterned sapphire substrate,” Thin Solid Films 519(8), 2398–2401 (2011).
[CrossRef]

T. S. Oh, H. Jeong, Y. S. Lee, J. D. Kim, T. H. Seo, H. Kim, A. H. Park, K. J. Lee, and E.-K. Suh, “Coupling of InGaN/GaN multiquantum-wells photoluminescence to surface plasmons in platinum nanocluster,” Appl. Phys. Lett. 95(11), 111112 (2009).
[CrossRef]

T. S. Oh, S. H. Kim, T. K. Kim, Y. S. Lee, H. Jeong, G. M. Yang, and E.-K. Suh, “GaN-based light-emitting diodes on micro-lens patterned sapphire substrate,” Jpn. J. Appl. Phys. 47(7), 5333–5336 (2008).
[CrossRef]

Liliental-Weber, Z.

Z. Liliental-Weber and D. Cherns, “Microstructure of lateral overgrown GaN layers,” J. Appl. Phys. 89(12), 7833–7840 (2001).
[CrossRef]

Lu, C.-Y.

C.-T. Chang, S.-K. Hsiao, E. Y. Chang, Y.-L. Hsiao, C.-Y. Lu, H.-C. Chang, K.-W. Cheng, and C.-T. Lee, “460-nm InGaN-based LEDs grown on fully inclined hemisphere-shape-patterned sapphire substrate with submicrometer spacing,” IEEE Photon. Technol. Lett. 21(19), 1366–1368 (2009).
[CrossRef]

Meyaard, D.

J. K. Kim, A. N. Noemaun, F. W. Mont, D. Meyaard, E. F. Schubert, D. J. Poxson, H. Kim, C. Sone, and Y. Park, “Elimination of total internal reflection in GaInN light-emitting diodes by graded-refractive-index micropillars,” Appl. Phys. Lett. 93(22), 221111 (2008).
[CrossRef]

Mitani, T.

M. Yamada, T. Mitani, Y. Narukawa, S. Shioji, I. Niki, S. Sonobe, K. Deguchi, M. Sano, and T. Mukai, “InGaN-based near-ultraviolet and blue-light-emitting diodes with high external quantum efficiency using a patterned sapphire substrate,” Jpn. J. Appl. Phys. 41(12B), L1431–L1433 (2002).
[CrossRef]

Mont, F. W.

J. K. Kim, A. N. Noemaun, F. W. Mont, D. Meyaard, E. F. Schubert, D. J. Poxson, H. Kim, C. Sone, and Y. Park, “Elimination of total internal reflection in GaInN light-emitting diodes by graded-refractive-index micropillars,” Appl. Phys. Lett. 93(22), 221111 (2008).
[CrossRef]

Mukai, T.

M. Yamada, T. Mitani, Y. Narukawa, S. Shioji, I. Niki, S. Sonobe, K. Deguchi, M. Sano, and T. Mukai, “InGaN-based near-ultraviolet and blue-light-emitting diodes with high external quantum efficiency using a patterned sapphire substrate,” Jpn. J. Appl. Phys. 41(12B), L1431–L1433 (2002).
[CrossRef]

Nakamura, S.

S. Nakamura, “Current status of GaN-based solid state lighting,” MRS Bull. 34(02), 101–107 (2009).
[CrossRef]

Nakano, Y.

Y. Nakano, O. Fujishima, and T. Kachi, “Effect of p-type activation ambient on acceptor levels in Mg-doped GaN,” J. Appl. Phys. 96(1), 415–419 (2004).
[CrossRef]

Narukawa, Y.

M. Yamada, T. Mitani, Y. Narukawa, S. Shioji, I. Niki, S. Sonobe, K. Deguchi, M. Sano, and T. Mukai, “InGaN-based near-ultraviolet and blue-light-emitting diodes with high external quantum efficiency using a patterned sapphire substrate,” Jpn. J. Appl. Phys. 41(12B), L1431–L1433 (2002).
[CrossRef]

Nicolay, S.

J.-F. Carlin, C. Zellweger, J. Dorsaz, S. Nicolay, G. Christmann, E. Feltin, R. Butté, and N. Grandjean, “Progresses in III-nitride distributed Bragg reflectors and microcavities using AlInN/GaN materials,” Phys. Status Solidi 242(11), 2326–2344 (2005) (b).
[CrossRef]

Niki, I.

M. Yamada, T. Mitani, Y. Narukawa, S. Shioji, I. Niki, S. Sonobe, K. Deguchi, M. Sano, and T. Mukai, “InGaN-based near-ultraviolet and blue-light-emitting diodes with high external quantum efficiency using a patterned sapphire substrate,” Jpn. J. Appl. Phys. 41(12B), L1431–L1433 (2002).
[CrossRef]

Noemaun, A. N.

J. K. Kim, A. N. Noemaun, F. W. Mont, D. Meyaard, E. F. Schubert, D. J. Poxson, H. Kim, C. Sone, and Y. Park, “Elimination of total internal reflection in GaInN light-emitting diodes by graded-refractive-index micropillars,” Appl. Phys. Lett. 93(22), 221111 (2008).
[CrossRef]

Oh, T. S.

T. S. Oh, H. Jeong, Y. S. Lee, T. H. Seo, A. H. Park, H. Kim, K. J. Lee, M. S. Jeong, and E.-K. Suh, “Defect structure originating from threading dislocations within the GaN film grown on a convex patterned sapphire substrate,” Thin Solid Films 519(8), 2398–2401 (2011).
[CrossRef]

T. S. Oh, H. Jeong, Y. S. Lee, J. D. Kim, T. H. Seo, H. Kim, A. H. Park, K. J. Lee, and E.-K. Suh, “Coupling of InGaN/GaN multiquantum-wells photoluminescence to surface plasmons in platinum nanocluster,” Appl. Phys. Lett. 95(11), 111112 (2009).
[CrossRef]

T. S. Oh, S. H. Kim, T. K. Kim, Y. S. Lee, H. Jeong, G. M. Yang, and E.-K. Suh, “GaN-based light-emitting diodes on micro-lens patterned sapphire substrate,” Jpn. J. Appl. Phys. 47(7), 5333–5336 (2008).
[CrossRef]

Onushkin, G. A.

G. A. Onushkin, S.-S. Hong, J.-H. Lee, J.-S. Park, J.-K. Son, M.-H. Kim, and Y. J. Park, “Local electroluminescence and time-resolved photoluminescence study of InGaN light-emitting diodes,” Appl. Phys. Lett. 95(10), 101904 (2009).
[CrossRef]

Park, A. H.

T. S. Oh, H. Jeong, Y. S. Lee, T. H. Seo, A. H. Park, H. Kim, K. J. Lee, M. S. Jeong, and E.-K. Suh, “Defect structure originating from threading dislocations within the GaN film grown on a convex patterned sapphire substrate,” Thin Solid Films 519(8), 2398–2401 (2011).
[CrossRef]

T. S. Oh, H. Jeong, Y. S. Lee, J. D. Kim, T. H. Seo, H. Kim, A. H. Park, K. J. Lee, and E.-K. Suh, “Coupling of InGaN/GaN multiquantum-wells photoluminescence to surface plasmons in platinum nanocluster,” Appl. Phys. Lett. 95(11), 111112 (2009).
[CrossRef]

Park, J.-S.

G. A. Onushkin, S.-S. Hong, J.-H. Lee, J.-S. Park, J.-K. Son, M.-H. Kim, and Y. J. Park, “Local electroluminescence and time-resolved photoluminescence study of InGaN light-emitting diodes,” Appl. Phys. Lett. 95(10), 101904 (2009).
[CrossRef]

Park, K. H.

H.-Y. Shin, S. K. Kwon, Y. I. Chang, M. J. Cho, and K. H. Park, “Reducing dislocation density in GaN films using a cone-shaped patterned sapphire substrate,” J. Cryst. Growth 311(17), 4167–4170 (2009).
[CrossRef]

Park, S.-H.

Park, Y.

J. K. Kim, A. N. Noemaun, F. W. Mont, D. Meyaard, E. F. Schubert, D. J. Poxson, H. Kim, C. Sone, and Y. Park, “Elimination of total internal reflection in GaInN light-emitting diodes by graded-refractive-index micropillars,” Appl. Phys. Lett. 93(22), 221111 (2008).
[CrossRef]

Park, Y. J.

G. A. Onushkin, S.-S. Hong, J.-H. Lee, J.-S. Park, J.-K. Son, M.-H. Kim, and Y. J. Park, “Local electroluminescence and time-resolved photoluminescence study of InGaN light-emitting diodes,” Appl. Phys. Lett. 95(10), 101904 (2009).
[CrossRef]

Poxson, D. J.

J. K. Kim, A. N. Noemaun, F. W. Mont, D. Meyaard, E. F. Schubert, D. J. Poxson, H. Kim, C. Sone, and Y. Park, “Elimination of total internal reflection in GaInN light-emitting diodes by graded-refractive-index micropillars,” Appl. Phys. Lett. 93(22), 221111 (2008).
[CrossRef]

Sano, M.

M. Yamada, T. Mitani, Y. Narukawa, S. Shioji, I. Niki, S. Sonobe, K. Deguchi, M. Sano, and T. Mukai, “InGaN-based near-ultraviolet and blue-light-emitting diodes with high external quantum efficiency using a patterned sapphire substrate,” Jpn. J. Appl. Phys. 41(12B), L1431–L1433 (2002).
[CrossRef]

Schubert, E. F.

J. K. Kim, A. N. Noemaun, F. W. Mont, D. Meyaard, E. F. Schubert, D. J. Poxson, H. Kim, C. Sone, and Y. Park, “Elimination of total internal reflection in GaInN light-emitting diodes by graded-refractive-index micropillars,” Appl. Phys. Lett. 93(22), 221111 (2008).
[CrossRef]

Seo, T. H.

T. S. Oh, H. Jeong, Y. S. Lee, T. H. Seo, A. H. Park, H. Kim, K. J. Lee, M. S. Jeong, and E.-K. Suh, “Defect structure originating from threading dislocations within the GaN film grown on a convex patterned sapphire substrate,” Thin Solid Films 519(8), 2398–2401 (2011).
[CrossRef]

T. S. Oh, H. Jeong, Y. S. Lee, J. D. Kim, T. H. Seo, H. Kim, A. H. Park, K. J. Lee, and E.-K. Suh, “Coupling of InGaN/GaN multiquantum-wells photoluminescence to surface plasmons in platinum nanocluster,” Appl. Phys. Lett. 95(11), 111112 (2009).
[CrossRef]

Shim, J.-I.

D.-H. Jang, J.-I. Shim, and K. Y. Yoo, “Theoretical analysis on the light extraction efficiency of GaN-based light-emitting diodes by using the ray tracing method,” J. Korean Phys. Soc. 54(6), 2373–2377 (2009).
[CrossRef]

Shin, H.-Y.

H.-Y. Shin, S. K. Kwon, Y. I. Chang, M. J. Cho, and K. H. Park, “Reducing dislocation density in GaN films using a cone-shaped patterned sapphire substrate,” J. Cryst. Growth 311(17), 4167–4170 (2009).
[CrossRef]

Shioji, S.

M. Yamada, T. Mitani, Y. Narukawa, S. Shioji, I. Niki, S. Sonobe, K. Deguchi, M. Sano, and T. Mukai, “InGaN-based near-ultraviolet and blue-light-emitting diodes with high external quantum efficiency using a patterned sapphire substrate,” Jpn. J. Appl. Phys. 41(12B), L1431–L1433 (2002).
[CrossRef]

Sigalas, M. M.

J. J. Wierer, M. R. Krames, J. E. Epler, N. F. Gardner, M. G. Craford, J. R. Wendt, J. A. Simmons, and M. M. Sigalas, “InGaN/GaN quantum-well heterostructures light-emitting diodes employing photonic crystal structures,” Appl. Phys. Lett. 84(19), 3885 (2004).
[CrossRef]

Simmons, J. A.

J. J. Wierer, M. R. Krames, J. E. Epler, N. F. Gardner, M. G. Craford, J. R. Wendt, J. A. Simmons, and M. M. Sigalas, “InGaN/GaN quantum-well heterostructures light-emitting diodes employing photonic crystal structures,” Appl. Phys. Lett. 84(19), 3885 (2004).
[CrossRef]

Son, J.-K.

G. A. Onushkin, S.-S. Hong, J.-H. Lee, J.-S. Park, J.-K. Son, M.-H. Kim, and Y. J. Park, “Local electroluminescence and time-resolved photoluminescence study of InGaN light-emitting diodes,” Appl. Phys. Lett. 95(10), 101904 (2009).
[CrossRef]

Sone, C.

J. K. Kim, A. N. Noemaun, F. W. Mont, D. Meyaard, E. F. Schubert, D. J. Poxson, H. Kim, C. Sone, and Y. Park, “Elimination of total internal reflection in GaInN light-emitting diodes by graded-refractive-index micropillars,” Appl. Phys. Lett. 93(22), 221111 (2008).
[CrossRef]

Sonobe, S.

M. Yamada, T. Mitani, Y. Narukawa, S. Shioji, I. Niki, S. Sonobe, K. Deguchi, M. Sano, and T. Mukai, “InGaN-based near-ultraviolet and blue-light-emitting diodes with high external quantum efficiency using a patterned sapphire substrate,” Jpn. J. Appl. Phys. 41(12B), L1431–L1433 (2002).
[CrossRef]

Suh, E. K.

T. V. Cuong, H. S. Cheong, H. G. Kim, H. Y. Kim, C.-H. Hong, E. K. Suh, H. K. Cho, and B. H. Kong, “enhanced light output from aligned micropit InGaN-based light emitting diodes using wet-etch sapphire patterning,” Appl. Phys. Lett. 90(13), 131107 (2007).
[CrossRef]

Suh, E.-K.

T. S. Oh, H. Jeong, Y. S. Lee, T. H. Seo, A. H. Park, H. Kim, K. J. Lee, M. S. Jeong, and E.-K. Suh, “Defect structure originating from threading dislocations within the GaN film grown on a convex patterned sapphire substrate,” Thin Solid Films 519(8), 2398–2401 (2011).
[CrossRef]

T. S. Oh, H. Jeong, Y. S. Lee, J. D. Kim, T. H. Seo, H. Kim, A. H. Park, K. J. Lee, and E.-K. Suh, “Coupling of InGaN/GaN multiquantum-wells photoluminescence to surface plasmons in platinum nanocluster,” Appl. Phys. Lett. 95(11), 111112 (2009).
[CrossRef]

T. S. Oh, S. H. Kim, T. K. Kim, Y. S. Lee, H. Jeong, G. M. Yang, and E.-K. Suh, “GaN-based light-emitting diodes on micro-lens patterned sapphire substrate,” Jpn. J. Appl. Phys. 47(7), 5333–5336 (2008).
[CrossRef]

Sung, Y.-J.

Wendt, J. R.

J. J. Wierer, M. R. Krames, J. E. Epler, N. F. Gardner, M. G. Craford, J. R. Wendt, J. A. Simmons, and M. M. Sigalas, “InGaN/GaN quantum-well heterostructures light-emitting diodes employing photonic crystal structures,” Appl. Phys. Lett. 84(19), 3885 (2004).
[CrossRef]

Wierer, J. J.

J. J. Wierer, M. R. Krames, J. E. Epler, N. F. Gardner, M. G. Craford, J. R. Wendt, J. A. Simmons, and M. M. Sigalas, “InGaN/GaN quantum-well heterostructures light-emitting diodes employing photonic crystal structures,” Appl. Phys. Lett. 84(19), 3885 (2004).
[CrossRef]

Yamada, M.

M. Yamada, T. Mitani, Y. Narukawa, S. Shioji, I. Niki, S. Sonobe, K. Deguchi, M. Sano, and T. Mukai, “InGaN-based near-ultraviolet and blue-light-emitting diodes with high external quantum efficiency using a patterned sapphire substrate,” Jpn. J. Appl. Phys. 41(12B), L1431–L1433 (2002).
[CrossRef]

Yang, G. M.

T. S. Oh, S. H. Kim, T. K. Kim, Y. S. Lee, H. Jeong, G. M. Yang, and E.-K. Suh, “GaN-based light-emitting diodes on micro-lens patterned sapphire substrate,” Jpn. J. Appl. Phys. 47(7), 5333–5336 (2008).
[CrossRef]

Yeom, G.-Y.

Yoo, K. Y.

D.-H. Jang, J.-I. Shim, and K. Y. Yoo, “Theoretical analysis on the light extraction efficiency of GaN-based light-emitting diodes by using the ray tracing method,” J. Korean Phys. Soc. 54(6), 2373–2377 (2009).
[CrossRef]

Zellweger, C.

J.-F. Carlin, C. Zellweger, J. Dorsaz, S. Nicolay, G. Christmann, E. Feltin, R. Butté, and N. Grandjean, “Progresses in III-nitride distributed Bragg reflectors and microcavities using AlInN/GaN materials,” Phys. Status Solidi 242(11), 2326–2344 (2005) (b).
[CrossRef]

Appl. Opt.

Appl. Phys. Lett.

G. A. Onushkin, S.-S. Hong, J.-H. Lee, J.-S. Park, J.-K. Son, M.-H. Kim, and Y. J. Park, “Local electroluminescence and time-resolved photoluminescence study of InGaN light-emitting diodes,” Appl. Phys. Lett. 95(10), 101904 (2009).
[CrossRef]

J. K. Kim, A. N. Noemaun, F. W. Mont, D. Meyaard, E. F. Schubert, D. J. Poxson, H. Kim, C. Sone, and Y. Park, “Elimination of total internal reflection in GaInN light-emitting diodes by graded-refractive-index micropillars,” Appl. Phys. Lett. 93(22), 221111 (2008).
[CrossRef]

T. S. Oh, H. Jeong, Y. S. Lee, J. D. Kim, T. H. Seo, H. Kim, A. H. Park, K. J. Lee, and E.-K. Suh, “Coupling of InGaN/GaN multiquantum-wells photoluminescence to surface plasmons in platinum nanocluster,” Appl. Phys. Lett. 95(11), 111112 (2009).
[CrossRef]

T. V. Cuong, H. S. Cheong, H. G. Kim, H. Y. Kim, C.-H. Hong, E. K. Suh, H. K. Cho, and B. H. Kong, “enhanced light output from aligned micropit InGaN-based light emitting diodes using wet-etch sapphire patterning,” Appl. Phys. Lett. 90(13), 131107 (2007).
[CrossRef]

J. J. Wierer, M. R. Krames, J. E. Epler, N. F. Gardner, M. G. Craford, J. R. Wendt, J. A. Simmons, and M. M. Sigalas, “InGaN/GaN quantum-well heterostructures light-emitting diodes employing photonic crystal structures,” Appl. Phys. Lett. 84(19), 3885 (2004).
[CrossRef]

IEEE Photon. Technol. Lett.

C.-T. Chang, S.-K. Hsiao, E. Y. Chang, Y.-L. Hsiao, C.-Y. Lu, H.-C. Chang, K.-W. Cheng, and C.-T. Lee, “460-nm InGaN-based LEDs grown on fully inclined hemisphere-shape-patterned sapphire substrate with submicrometer spacing,” IEEE Photon. Technol. Lett. 21(19), 1366–1368 (2009).
[CrossRef]

J. Appl. Phys.

Y. Nakano, O. Fujishima, and T. Kachi, “Effect of p-type activation ambient on acceptor levels in Mg-doped GaN,” J. Appl. Phys. 96(1), 415–419 (2004).
[CrossRef]

Z. Liliental-Weber and D. Cherns, “Microstructure of lateral overgrown GaN layers,” J. Appl. Phys. 89(12), 7833–7840 (2001).
[CrossRef]

J. Cryst. Growth

H.-Y. Shin, S. K. Kwon, Y. I. Chang, M. J. Cho, and K. H. Park, “Reducing dislocation density in GaN films using a cone-shaped patterned sapphire substrate,” J. Cryst. Growth 311(17), 4167–4170 (2009).
[CrossRef]

J. Korean Phys. Soc.

D.-H. Jang, J.-I. Shim, and K. Y. Yoo, “Theoretical analysis on the light extraction efficiency of GaN-based light-emitting diodes by using the ray tracing method,” J. Korean Phys. Soc. 54(6), 2373–2377 (2009).
[CrossRef]

Jpn. J. Appl. Phys.

M. Yamada, T. Mitani, Y. Narukawa, S. Shioji, I. Niki, S. Sonobe, K. Deguchi, M. Sano, and T. Mukai, “InGaN-based near-ultraviolet and blue-light-emitting diodes with high external quantum efficiency using a patterned sapphire substrate,” Jpn. J. Appl. Phys. 41(12B), L1431–L1433 (2002).
[CrossRef]

T. S. Oh, S. H. Kim, T. K. Kim, Y. S. Lee, H. Jeong, G. M. Yang, and E.-K. Suh, “GaN-based light-emitting diodes on micro-lens patterned sapphire substrate,” Jpn. J. Appl. Phys. 47(7), 5333–5336 (2008).
[CrossRef]

MRS Bull.

S. Nakamura, “Current status of GaN-based solid state lighting,” MRS Bull. 34(02), 101–107 (2009).
[CrossRef]

Phys. Status Solidi

J.-F. Carlin, C. Zellweger, J. Dorsaz, S. Nicolay, G. Christmann, E. Feltin, R. Butté, and N. Grandjean, “Progresses in III-nitride distributed Bragg reflectors and microcavities using AlInN/GaN materials,” Phys. Status Solidi 242(11), 2326–2344 (2005) (b).
[CrossRef]

Thin Solid Films

T. S. Oh, H. Jeong, Y. S. Lee, T. H. Seo, A. H. Park, H. Kim, K. J. Lee, M. S. Jeong, and E.-K. Suh, “Defect structure originating from threading dislocations within the GaN film grown on a convex patterned sapphire substrate,” Thin Solid Films 519(8), 2398–2401 (2011).
[CrossRef]

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Figures (6)

Fig. 1
Fig. 1

(a) SEM image of the CM array monolithically fabricated on a sapphire substrate. The diameter and distance with hexagonal arrangement are 3 and 2 μm, respectively. (b) Atomic force microscopy image of the LED surface. (c) Cross sectional TEM image of the LED epistructure on sapphire with CM array.

Fig. 2
Fig. 2

(a) Room temperature NSOM-PL image recorded with near field probe aperture of 100 nm and (b) EL image for same sample with injection current of 5 mA. The regions surrounded by dashed circles indicate the convex patterned region of a sapphire substrate. (c) EL spectra recorded from (A), (B) and (C) spots.

Fig. 3
Fig. 3

Depending on various focal plane depths, confocal EL images for the LEDs with CM array. The focal plane depths are (b) the interface between LED epi and sapphire substrate, (c) 0.5 µm, (d) 1 µm, (e) 1.5 µm, (f) 2 µm, (g) 2.5 µm, (h) 3 µm above the interface and (i) LED surface. The injection current was 5 mA. The measured position is the same.

Fig. 4
Fig. 4

X-Z scanned confocal EL mapping image of the LED with CM array.

Fig. 5
Fig. 5

EL output power of LEDs with and without CMs as a function of injection current. The inset shows IQE values of the two LED samples depending on excitation power density.

Fig. 6
Fig. 6

Ray tracing results of the (a) conventional LED and (b) the LED with CMs. (c) The simulated and measured far-field EL intensity ratios (gain) of two LED samples as a function of polar angles..

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