Abstract

The enhancement of light extraction efficiency of InGaN quantum well light emitting diodes (LEDs) was achieved by employing the refractive index matched TiO<sub>2</sub> microsphere arrays. The optimization studies of the dipping method and rapid convective deposition (RCD) method were carried out for the deposition of TiO<sub>2</sub> microsphere arrays onto LEDs. The two-dimensional (2D) close-packed TiO<sub>2</sub> microsphere arrays were deposited by the using optimized conditions of the dipping and RCD methods, respectively. The light extraction efficiencies of LEDs under electrical injection were enhanced by 1.8–1.9 times by utilizing 520-nm diameter amorphous and anatase TiO<sub>2</sub> microspheres via the two deposition methods.

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2012 (5)

2011 (8)

S. Chhajed, W. Lee, J. Cho, E. F. Schubert, J. K. Kim, "Strong light extraction enhancement in GaInN light-emitting diodes by using self-organized nanoscale patterning of p-type GaN," Appl. Phys. Lett. 98, 071102-1-071102-3 (2011).

X. H. Li, R. Song, Y. K. Ee, P. Kumnorkaew, J. F. Gilchrist, N. Tansu, "Light extraction efficiency and radiation patterns of III-nitride light emitting diodes with colloidal microlens arrays with various aspect ratios," IEEE Photon. J. 3, 489-499 (2011).

H. Zhao, G. Y. Liu, J. Zhang, J. D. Poplawsky, V. Dierolf, N. Tansu, "Approaches for high internal quantum efficiency green InGaN light-emitting diodes with large overlap quantum wells," Opt. Express 19, A991-A1007 (2011).

H. Zhao, J. Zhang, G. Liu, N. Tansu, "Surface plasmon dispersion engineering via double-metallic Au/Ag layers for III-nitride based light emitting diodes," Appl. Phys. Lett. 98, 151115 (2011).

Y. Li, S. You, M. W. Zhu, L. Zhao, W. T. Hou, T. Detchprohm, Y. Taniguchi, N. Tamura, S. Tanaka, C. Wetzel, "Defect-reduced green GaInN/GaN light-emitting diode on nanopatterned sapphire," Appl. Phys. Lett. 98, (2011) Art. 151102.

B. N. Pantha, I. Feng, K. Aryal, J. Li, J. Y. Lin, H. X. Jiang, "Erbium-doped AlInGaN alloys as high-temperature thermoelectric materials," Appl. Phys. Express 4, 051001-1-051001-3 (2011).

J. Zhang, H. Tong, G. Liu, J. A. Herbsommer, G. S. Huang, N. Tansu, "Characterizations of seebeck coefficients and thermoelectric figures of merit for AlInN alloys with various in-contents," J. Appl. Phys. 109, 053706-1-053706-6 (2011).

E. Rangel, E. Matioli, Y. S. Choi, C. Weisbuch, J. S. Speck, E. L. Hu, "Directionality control through selective excitation of low-order guided modes in thin-film InGaN photonic crystal light-emitting diodes," Appl. Phys. Lett. 98, 081104-1-081104-3 (2011).

2010 (6)

K. Aryal, B. N. Pantha, J. Li, J. Y. Lin, H. X. Jiang, "Hydrogen generation by solar water splitting using p-InGaN photoelectrochemical cells," Appl. Phys. Lett. 96, 052110-1-052110-3 (2010).

X. Li, H. Y. Liu, X. Ni, U. Ozgur, H. Morkoc, "Effect of carrier spillover and auger recombination on the efficiency droop in InGaN-based blue LEDs," Superlattices and Microstructures 47, 118-122 (2010).

U. Ozgur, H. Liu, X. Li, H. Morkoc, "GaN-based light-emitting diodes: Efficiency at high injection levels," Proc. IEEE 98, 1180-1196 (2010).

A. Venkatachalam, B. Klein, J.-H. Ryou, S. C. Shen, R. D. Dupuis, P. D. Yoder, "Design strategies for InGaN-based green lasers," IEEE J. Quantum Electron. 46, 238-245 (2010).

H. Yoshida, M. Kuwabara, Y. Yamashita, K. Uchiyama, H. Kan, "Radiative and nonradiative recombination in an ultraviolet GaN/AlGaN multiple-quantum-well laser diode," Appl. Phys. Lett. 96, 211122-1-211122-3 (2010).

C. T. Liao, M. C. Tsai, B. T. Liou, S. H. Yen, Y. K. Kuo, "Improvement in output power of a 460 nm InGaN light-emitting diode using staggered quantum well," J. Appl. Phys. 108, 063107-1-063107-6 (2010).

2009 (11)

J. H. Ryou, P. D. Yoder, J. Liu, Z. Lochner, H. Kim, S. Choi, H. J. Kim, R. D. Dupuis, "Control of quantum-confined stark effect in InGaN-based quantum wells," IEEE J. Sel. Topics Quantum Electron. 15, 1080-1091 (2009).

K. Okamoto, Y. Kawakami, "High-efficiency InGaN/GaN light emitters based on nanophotonics and plasmonics," IEEE J. Sel. Topics Quantum Electron. 15, 1199-1209 (2009).

S. H. Park, D. Ahn, J. W. Kim, "High-efficiency staggered 530 nm InGaN/InGaN/GaN quantum-well light-emitting diodes," Appl. Phys. Lett. 94, 041109-1-041109-3 (2009).

D. Queren, A. Avramescu, G. Bruderl, A. Breidenassel, M. Schillgalies, S. Lutgen, U. Strau, "500 nm electrically driven InGaN based laser diodes," Appl. Phys. Lett. 94, 081119-1-081119-3 (2009).

Y. K. Ee, J. M. Biser, W. J. Cao, H. M. Chan, R. P. Vinci, N. Tansu, "Metalorganic vapor phase epitaxy of III-nitride light-emitting diodes on nanopatterned AGOG sapphire substrate by abbreviated growth mode," IEEE J. Sel. Topics Quantum Electron. 15, 1066-1072 (2009).

R. Dahal, B. Pantha, J. Li, J. Y. Lin, H. X. Jiang, "InGaN/GaN multiple quantum well solar cells with long operating wavelengths," Appl. Phys. Lett. 94, 063505-1-063505-3 (2009).

J. J. Wierer, A. David, M. M. Megens, "III-nitride photonic-crystal light-emitting diodes with high extraction efficiency," Nat. Photon. 3, 163-169 (2009).

Y. K. Ee, P. Kumnorkaew, R. A. Arif, H. Tong, J. F. Gilchrist, N. Tansu, "Light extraction efficiency enhancement of InGaN quantum wells light-emitting diodes with polydimethylsiloxane concave microstructures," Opt. Express 17, 13747-13757 (2009).

M. H. Crawford, "LEDs for solid-state lighting: Performance challenges and recent advances," IEEE J. Sel. Topics Quantum Electron. 15, 1028-1040 (2009).

T. Jung, L. K. Lee, P. C. Ku, "Novel epitaxial nanostructures for the improvement of InGaN LEDs efficiency," IEEE J. Sel. Topics Quantum Electron. 15, 1073-1079 (2009).

Y. K. Ee, P. Kumnorkaew, R. A. Arif, H. Tong, H. Zhao, J. F. Gilchrist, N. Tansu, "Optimization of light extraction efficiency of III-nitride LEDs with self-assembled colloidal-based microlenses," IEEE J. Sel. Topics Quantum Electron. 15, 1218-1225 (2009).

2008 (5)

P. Kumnorkaew, Y. K. Ee, N. Tansu, J. F. Gilchrist, "Investigation of the deposition of microsphere monolayers for fabrication of microlens arrays," Langmuir 24, 12150-12157 (2008).

E. I. Ross-Medgaarden, I. E. Wachs, W. V. Knowles, A. Burrows, C. J. Kiely, M. S. Wong, "Tuning the electronic and molecular structure of catalytic active sites with titania nanoligands," J. Amer. Chem. Soc. 131, 680-687 (2008).

I. Moreno, C. C. Sun, "Modeling the radiation pattern of LEDs," Opt. Express 16, 1808-1819 (2008).

C. J. Neufeld, N. G. Toledo, S. C. Cruz, M. Iza, S. P. DenBaars, U. K. Mishra, "High quantum efficiency InGaN/GaN solar cells with 2.95 eV band gap," Appl. Phys. Lett. 93, 143502-1-143502-3 (2008).

M. F. Schubert, J. Xu, J. K. Kim, E. F. Schubert, M. H. Kim, S. Yoon, S. M. Lee, C. Sone, T. Sakong, Y. Park, "Polarization-matched GaInN/AlGaInN multi-quantum-well light-emitting diodes with reduced efficiency droop," Appl. Phys. Lett. 93, 041102-1-041102-3 (2008).

2007 (9)

N. F. Gardner, G. O. Muller, Y. C. Shen, G. Chen, S. Watanabe, W. Gotz, M. R. Krames, "Blue-emitting InGaN-GaN double-heterostructure light emitting diodes reaching maximum quantum efficiency above 200 A/cm2," Appl. Phys. Lett. 91, 243506 (2007).

R. A. Arif, Y. K. Ee, N. Tansu, "Polarization engineering via staggered InGaN quantum wells for radiative efficiency enhancement of light emitting diodes," Appl. Phys. Lett. 91, 091110 (2007).

R. M. Farrell, D. F. Feezell, M. C. Schmidt, D. A. Haeger, K. M. Kelchner, K. Iso, H. Yamada, M. Saito, K. Fujito, D. A. Cohen, J. S. Speck, S. P. DenBaars, S. Nakamura, "Continuous-wave operation of AlGaN-cladding-free nonpolar m-plane InGaN/GaN laser diodes," Jpn. J. Appl. Phys. 46, L761-L763 (2007).

M. C. Schmidt, K.-C. Kim, R. M. Farrell, D. F. Feezell, D. A. Cohen, M. Saito, K. Fujito, J. S. Speck, S. P. Denbaars, S. Nakamura, "Demonstration of nonpolar m-plane InGaN/GaN laser diodes," Jpn. J. Appl. Phys. 46, L190-L191 (2007).

O. Jani, I. Ferguson, C. Honsberg, S. Kurtz, "Design and characterization of GaN/InGaN solar cells," Appl. Phys. Lett. 91, 132117-1-132117-3 (2007).

Q. Xi, M. F. Schubert, J. K. Kim, E. F. Schubert, M. Chen, S. Y. Lin, W. Liu, J. A. Smart, "Optical thin-film materials with low refractive index for broadband elimination of Fresnel reflection," Nat. Photon. 1, 176-179 (2007).

S. J. Lee, J. Lee, S. Kim, H. Jeon, "Fabrication of reflective GaN mesa sidewalls for the application to high extraction efficiency LEDs," Phys. Stat. Solidi (c) 4, 2625-2628 (2007).

M. Zhang, G. Lin, C. Dong, L. Wen, "Amorphous TiO2 films with high refractive index deposited by pulsed bias arc ion plating," Surf. Coat. Tech. 201, 7252-7258 (2007).

Y. K. Ee, P. Kumnorkaew, R. A. Arif, J. F. Gilchrist, N. Tansu, "Enhancement of light extraction efficiency of InGaN quantum wells light emitting diodes using SiO2/polystyrene microlens arrays," Appl. Phys. Lett. 91, 221107-1-221107-3 (2007).

2006 (1)

J. Q. Xi, H. Luo, A. J. Pasquale, J. K. Kim, E. F. Schubert, "Enhanced light extraction in GaInN light-emitting diode with pyramid reflector," IEEE Photon. Technol. Lett. 18, 2347-2349 (2006).

2005 (4)

D. Kim, C. Cho, Y. Roh, H. Jeon, Y. S. Park, J. Cho, J. S. Im, C. Sone, Y. Park, W. J. Choi, Q. Park, "Enhanced light extraction from GaN-based light-emitting diodes with holographically generated two-dimensional photonic crystal patterns," Appl. Phys. Lett. 87, 203508-1-203508-3 (2005).

T. Kim, A. J. Danner, K. D. Choquette, "Enhancement in external quantum efficiency of blue light-emitting diode by photonic crystal surface grating," Elect. Lett. 41, 1138-1139 (2005).

C. F. Lin, Z. J. Yang, J. H. Zheng, J. J. Dai, "Enhanced light output in nitride-based light-emitting diodes by roughening the mesa sidewall," IEEE Photon. Technol. Lett. 17, 2038-2040 (2005).

H. W. Huang, J. T. Chu, C. C. Kao, T. H. Hseuh, T. C. Lu, H. C. Kuo, S. C. Wang, C. C. Yu, "Enhanced light output of an InGaN/GaN light emitting diode with a nano-roughened p-GaN surface," Nanotechnol. 16, 1844-1848 (2005).

2004 (3)

H. W. Choi, C. Liu, E. Gu, G. McConnell, J. M. Girkin, I. M. Watson, M. D. Dawson, "GaN micro-light-emitting diode arrays with monolithically integrated sapphire microlenses," Appl. Phys. Lett. 84, 2253-1-2253-3 (2004).

T. Fujii, Y. Gao, R. Sharma, E. L. Hu, S. P. DenBaars, S. Nakamura, "Increase in the extraction efficiency of GaN-based light-emitting diodes via surface roughening," Appl. Phys. Lett. 84, 855-1-855-3 (2004).

Y. Gao, Y. Masuda, K. Kuomoto, "Micropatterning of TiO2 thin film in an aqueous peroxotitanate solution," Chem. Mater. 16, 1062-1067 (2004).

2003 (2)

C. Huh, K. S. Lee, E. J. Kang, S. J. Park, "Improved light-output and electrical performance of InGaN-based light-emitting diode by microroughening of the p-GaN surface," J. Appl. Phys. 93, 9383-9385 (2003).

M. Kneissl, D. W. Treat, M. Teepe, N. Miyashita, N. M. Johnson, "Continuous-wave operation of ultraviolet InGaN/InAlGaN multiple-quantum-well laser diodes," Appl. Phys. Lett. 82, 2386-2388 (2003).

2002 (2)

Z. Z. Gu, A. Fujishima, O. Sato, "Fabrication of high-quality opal films with controllable thickness," Chem. Mater. 14, 760-765 (2002).

D. D. Koleske, A. J. Fischer, A. A. Allerman, C. C. Mitchell, K. C. Cross, S. R. Kurtz, J. J. Figiel, K. W. Fullmer, W. G. Breiland, "Improved brightness of 380 nm GaN light emitting diodes through intentional delay of the nucleation island coalescence," Appl. Phys. Lett. 81, 1940-1942 (2002).

1998 (1)

X. Li, S. G. Bishop, J. J. Coleman, "GaN epitaxial lateral overgrowth and optical characterization," Appl. Phys. Lett. 73, 1179-1181 (1998).

Appl. Phys. Express (1)

B. N. Pantha, I. Feng, K. Aryal, J. Li, J. Y. Lin, H. X. Jiang, "Erbium-doped AlInGaN alloys as high-temperature thermoelectric materials," Appl. Phys. Express 4, 051001-1-051001-3 (2011).

Appl. Phys. Lett. (22)

T. Fujii, Y. Gao, R. Sharma, E. L. Hu, S. P. DenBaars, S. Nakamura, "Increase in the extraction efficiency of GaN-based light-emitting diodes via surface roughening," Appl. Phys. Lett. 84, 855-1-855-3 (2004).

H. W. Choi, C. Liu, E. Gu, G. McConnell, J. M. Girkin, I. M. Watson, M. D. Dawson, "GaN micro-light-emitting diode arrays with monolithically integrated sapphire microlenses," Appl. Phys. Lett. 84, 2253-1-2253-3 (2004).

D. Queren, A. Avramescu, G. Bruderl, A. Breidenassel, M. Schillgalies, S. Lutgen, U. Strau, "500 nm electrically driven InGaN based laser diodes," Appl. Phys. Lett. 94, 081119-1-081119-3 (2009).

H. Yoshida, M. Kuwabara, Y. Yamashita, K. Uchiyama, H. Kan, "Radiative and nonradiative recombination in an ultraviolet GaN/AlGaN multiple-quantum-well laser diode," Appl. Phys. Lett. 96, 211122-1-211122-3 (2010).

M. Kneissl, D. W. Treat, M. Teepe, N. Miyashita, N. M. Johnson, "Continuous-wave operation of ultraviolet InGaN/InAlGaN multiple-quantum-well laser diodes," Appl. Phys. Lett. 82, 2386-2388 (2003).

O. Jani, I. Ferguson, C. Honsberg, S. Kurtz, "Design and characterization of GaN/InGaN solar cells," Appl. Phys. Lett. 91, 132117-1-132117-3 (2007).

C. J. Neufeld, N. G. Toledo, S. C. Cruz, M. Iza, S. P. DenBaars, U. K. Mishra, "High quantum efficiency InGaN/GaN solar cells with 2.95 eV band gap," Appl. Phys. Lett. 93, 143502-1-143502-3 (2008).

R. Dahal, B. Pantha, J. Li, J. Y. Lin, H. X. Jiang, "InGaN/GaN multiple quantum well solar cells with long operating wavelengths," Appl. Phys. Lett. 94, 063505-1-063505-3 (2009).

K. Aryal, B. N. Pantha, J. Li, J. Y. Lin, H. X. Jiang, "Hydrogen generation by solar water splitting using p-InGaN photoelectrochemical cells," Appl. Phys. Lett. 96, 052110-1-052110-3 (2010).

D. D. Koleske, A. J. Fischer, A. A. Allerman, C. C. Mitchell, K. C. Cross, S. R. Kurtz, J. J. Figiel, K. W. Fullmer, W. G. Breiland, "Improved brightness of 380 nm GaN light emitting diodes through intentional delay of the nucleation island coalescence," Appl. Phys. Lett. 81, 1940-1942 (2002).

X. Li, S. G. Bishop, J. J. Coleman, "GaN epitaxial lateral overgrowth and optical characterization," Appl. Phys. Lett. 73, 1179-1181 (1998).

R. A. Arif, Y. K. Ee, N. Tansu, "Polarization engineering via staggered InGaN quantum wells for radiative efficiency enhancement of light emitting diodes," Appl. Phys. Lett. 91, 091110 (2007).

S. H. Park, D. Ahn, J. W. Kim, "High-efficiency staggered 530 nm InGaN/InGaN/GaN quantum-well light-emitting diodes," Appl. Phys. Lett. 94, 041109-1-041109-3 (2009).

M. F. Schubert, J. Xu, J. K. Kim, E. F. Schubert, M. H. Kim, S. Yoon, S. M. Lee, C. Sone, T. Sakong, Y. Park, "Polarization-matched GaInN/AlGaInN multi-quantum-well light-emitting diodes with reduced efficiency droop," Appl. Phys. Lett. 93, 041102-1-041102-3 (2008).

N. F. Gardner, G. O. Muller, Y. C. Shen, G. Chen, S. Watanabe, W. Gotz, M. R. Krames, "Blue-emitting InGaN-GaN double-heterostructure light emitting diodes reaching maximum quantum efficiency above 200 A/cm2," Appl. Phys. Lett. 91, 243506 (2007).

H. Zhao, J. Zhang, G. Liu, N. Tansu, "Surface plasmon dispersion engineering via double-metallic Au/Ag layers for III-nitride based light emitting diodes," Appl. Phys. Lett. 98, 151115 (2011).

Y. Li, S. You, M. W. Zhu, L. Zhao, W. T. Hou, T. Detchprohm, Y. Taniguchi, N. Tamura, S. Tanaka, C. Wetzel, "Defect-reduced green GaInN/GaN light-emitting diode on nanopatterned sapphire," Appl. Phys. Lett. 98, (2011) Art. 151102.

D. Kim, C. Cho, Y. Roh, H. Jeon, Y. S. Park, J. Cho, J. S. Im, C. Sone, Y. Park, W. J. Choi, Q. Park, "Enhanced light extraction from GaN-based light-emitting diodes with holographically generated two-dimensional photonic crystal patterns," Appl. Phys. Lett. 87, 203508-1-203508-3 (2005).

E. Rangel, E. Matioli, Y. S. Choi, C. Weisbuch, J. S. Speck, E. L. Hu, "Directionality control through selective excitation of low-order guided modes in thin-film InGaN photonic crystal light-emitting diodes," Appl. Phys. Lett. 98, 081104-1-081104-3 (2011).

M. Ma, J. Cho, E. F. Schubert, Y. Park, G. B. Kim, C. Sone, "Strong light-extraction enhancement in GaInN light-emitting diodes patterned with TiO2 micro-pillars with tapered sidewalls," Appl. Phys. Lett. 101, 141105 (2012).

Y. K. Ee, P. Kumnorkaew, R. A. Arif, J. F. Gilchrist, N. Tansu, "Enhancement of light extraction efficiency of InGaN quantum wells light emitting diodes using SiO2/polystyrene microlens arrays," Appl. Phys. Lett. 91, 221107-1-221107-3 (2007).

S. Chhajed, W. Lee, J. Cho, E. F. Schubert, J. K. Kim, "Strong light extraction enhancement in GaInN light-emitting diodes by using self-organized nanoscale patterning of p-type GaN," Appl. Phys. Lett. 98, 071102-1-071102-3 (2011).

Chem. Mater. (2)

Y. Gao, Y. Masuda, K. Kuomoto, "Micropatterning of TiO2 thin film in an aqueous peroxotitanate solution," Chem. Mater. 16, 1062-1067 (2004).

Z. Z. Gu, A. Fujishima, O. Sato, "Fabrication of high-quality opal films with controllable thickness," Chem. Mater. 14, 760-765 (2002).

Elect. Lett. (1)

T. Kim, A. J. Danner, K. D. Choquette, "Enhancement in external quantum efficiency of blue light-emitting diode by photonic crystal surface grating," Elect. Lett. 41, 1138-1139 (2005).

IEEE J. Quantum Electron. (1)

A. Venkatachalam, B. Klein, J.-H. Ryou, S. C. Shen, R. D. Dupuis, P. D. Yoder, "Design strategies for InGaN-based green lasers," IEEE J. Quantum Electron. 46, 238-245 (2010).

IEEE J. Sel. Topics Quantum Electron. (6)

Y. K. Ee, J. M. Biser, W. J. Cao, H. M. Chan, R. P. Vinci, N. Tansu, "Metalorganic vapor phase epitaxy of III-nitride light-emitting diodes on nanopatterned AGOG sapphire substrate by abbreviated growth mode," IEEE J. Sel. Topics Quantum Electron. 15, 1066-1072 (2009).

K. Okamoto, Y. Kawakami, "High-efficiency InGaN/GaN light emitters based on nanophotonics and plasmonics," IEEE J. Sel. Topics Quantum Electron. 15, 1199-1209 (2009).

M. H. Crawford, "LEDs for solid-state lighting: Performance challenges and recent advances," IEEE J. Sel. Topics Quantum Electron. 15, 1028-1040 (2009).

J. H. Ryou, P. D. Yoder, J. Liu, Z. Lochner, H. Kim, S. Choi, H. J. Kim, R. D. Dupuis, "Control of quantum-confined stark effect in InGaN-based quantum wells," IEEE J. Sel. Topics Quantum Electron. 15, 1080-1091 (2009).

T. Jung, L. K. Lee, P. C. Ku, "Novel epitaxial nanostructures for the improvement of InGaN LEDs efficiency," IEEE J. Sel. Topics Quantum Electron. 15, 1073-1079 (2009).

Y. K. Ee, P. Kumnorkaew, R. A. Arif, H. Tong, H. Zhao, J. F. Gilchrist, N. Tansu, "Optimization of light extraction efficiency of III-nitride LEDs with self-assembled colloidal-based microlenses," IEEE J. Sel. Topics Quantum Electron. 15, 1218-1225 (2009).

IEEE Photon. J. (1)

X. H. Li, R. Song, Y. K. Ee, P. Kumnorkaew, J. F. Gilchrist, N. Tansu, "Light extraction efficiency and radiation patterns of III-nitride light emitting diodes with colloidal microlens arrays with various aspect ratios," IEEE Photon. J. 3, 489-499 (2011).

IEEE Photon. Technol. Lett. (2)

J. Q. Xi, H. Luo, A. J. Pasquale, J. K. Kim, E. F. Schubert, "Enhanced light extraction in GaInN light-emitting diode with pyramid reflector," IEEE Photon. Technol. Lett. 18, 2347-2349 (2006).

C. F. Lin, Z. J. Yang, J. H. Zheng, J. J. Dai, "Enhanced light output in nitride-based light-emitting diodes by roughening the mesa sidewall," IEEE Photon. Technol. Lett. 17, 2038-2040 (2005).

J. Amer. Chem. Soc. (1)

E. I. Ross-Medgaarden, I. E. Wachs, W. V. Knowles, A. Burrows, C. J. Kiely, M. S. Wong, "Tuning the electronic and molecular structure of catalytic active sites with titania nanoligands," J. Amer. Chem. Soc. 131, 680-687 (2008).

J. Appl. Phys. (3)

J. Zhang, H. Tong, G. Liu, J. A. Herbsommer, G. S. Huang, N. Tansu, "Characterizations of seebeck coefficients and thermoelectric figures of merit for AlInN alloys with various in-contents," J. Appl. Phys. 109, 053706-1-053706-6 (2011).

C. Huh, K. S. Lee, E. J. Kang, S. J. Park, "Improved light-output and electrical performance of InGaN-based light-emitting diode by microroughening of the p-GaN surface," J. Appl. Phys. 93, 9383-9385 (2003).

C. T. Liao, M. C. Tsai, B. T. Liou, S. H. Yen, Y. K. Kuo, "Improvement in output power of a 460 nm InGaN light-emitting diode using staggered quantum well," J. Appl. Phys. 108, 063107-1-063107-6 (2010).

Jpn. J. Appl. Phys. (2)

R. M. Farrell, D. F. Feezell, M. C. Schmidt, D. A. Haeger, K. M. Kelchner, K. Iso, H. Yamada, M. Saito, K. Fujito, D. A. Cohen, J. S. Speck, S. P. DenBaars, S. Nakamura, "Continuous-wave operation of AlGaN-cladding-free nonpolar m-plane InGaN/GaN laser diodes," Jpn. J. Appl. Phys. 46, L761-L763 (2007).

M. C. Schmidt, K.-C. Kim, R. M. Farrell, D. F. Feezell, D. A. Cohen, M. Saito, K. Fujito, J. S. Speck, S. P. Denbaars, S. Nakamura, "Demonstration of nonpolar m-plane InGaN/GaN laser diodes," Jpn. J. Appl. Phys. 46, L190-L191 (2007).

Langmuir (1)

P. Kumnorkaew, Y. K. Ee, N. Tansu, J. F. Gilchrist, "Investigation of the deposition of microsphere monolayers for fabrication of microlens arrays," Langmuir 24, 12150-12157 (2008).

Nanotechnol. (1)

H. W. Huang, J. T. Chu, C. C. Kao, T. H. Hseuh, T. C. Lu, H. C. Kuo, S. C. Wang, C. C. Yu, "Enhanced light output of an InGaN/GaN light emitting diode with a nano-roughened p-GaN surface," Nanotechnol. 16, 1844-1848 (2005).

Nat. Photon. (2)

J. J. Wierer, A. David, M. M. Megens, "III-nitride photonic-crystal light-emitting diodes with high extraction efficiency," Nat. Photon. 3, 163-169 (2009).

Q. Xi, M. F. Schubert, J. K. Kim, E. F. Schubert, M. Chen, S. Y. Lin, W. Liu, J. A. Smart, "Optical thin-film materials with low refractive index for broadband elimination of Fresnel reflection," Nat. Photon. 1, 176-179 (2007).

Opt. Express (5)

Opt. Mater. Express (2)

Phys. Stat. Solidi (c) (1)

S. J. Lee, J. Lee, S. Kim, H. Jeon, "Fabrication of reflective GaN mesa sidewalls for the application to high extraction efficiency LEDs," Phys. Stat. Solidi (c) 4, 2625-2628 (2007).

Proc. IEEE (1)

U. Ozgur, H. Liu, X. Li, H. Morkoc, "GaN-based light-emitting diodes: Efficiency at high injection levels," Proc. IEEE 98, 1180-1196 (2010).

Superlattices and Microstructures (1)

X. Li, H. Y. Liu, X. Ni, U. Ozgur, H. Morkoc, "Effect of carrier spillover and auger recombination on the efficiency droop in InGaN-based blue LEDs," Superlattices and Microstructures 47, 118-122 (2010).

Surf. Coat. Tech. (1)

M. Zhang, G. Lin, C. Dong, L. Wen, "Amorphous TiO2 films with high refractive index deposited by pulsed bias arc ion plating," Surf. Coat. Tech. 201, 7252-7258 (2007).

Other (2)

P. F. Zhu, J. Zhang, G. Y. Liu, N. Tansu, "FDTD modeling of InGaN-based light-emitting diodes with microsphere arrays," Proc. IEEE Photon. Conf. 2012 (2012).

J. K. Kim, M. F. Schubert, J. Q. Xi, F. W. Mont, E. F. Schubert, "Enhancement of light extraction in GaInN light-emitting diodes with graded-index indium tin oxide layer," Conf. Lasers Electro-Optics/Int. Quantum Electronics Conf. (CLEO/IQEC) BaltimoreMD (2007) Paper CTuI1.

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