Abstract

A tapered AlGaN electron blocking layer with step-graded aluminum composition is analyzed in nitride-based blue light-emitting diode (LED) numerically and experimentally. The energy band diagrams, electrostatic fields, carrier concentration, electron current density profiles, and hole transmitting probability are investigated. The simulation results demonstrated that such tapered structure can effectively enhance the hole injection efficiency as well as the electron confinement. Consequently, the LED with a tapered EBL grown by metal-organic chemical vapor deposition exhibits reduced efficiency droop behavior of 29% as compared with 44% for original LED, which reflects the improvement in hole injection and electron overflow in our design.

© 2014 Optical Society of America

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    [CrossRef]
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    [CrossRef] [PubMed]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef] [PubMed]
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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]
  26. J.-R. Chen, C.-H. Lee, T.-S. Ko, Y.-A. Chang, T.-C. Lu, H.-C. Kuo, Y.-K. Kuo, S.-C. Wang, “Effects of built-in polarization and carrier overflow on InGaN quantum-well lasers with electron blocking layers,” J. Lightwave Technol. 26(3), 329–337 (2008).
    [CrossRef]
  27. H. J. Kim, S. Choi, S.-S. Kim, J.-H. Ryou, P. D. Yoder, R. D. Dupuis, A. M. Fischer, K. Sun, F. A. Ponce, “Improvement of quantum efficiency by employing active-layer-friendly lattice-matched InAlN electron blocking layer in green light-emitting diodes,” Appl. Phys. Lett. 96(10), 101102 (2010).
    [CrossRef]
  28. V. Fiorentini, F. Bernardini, O. Ambacher, “Evidence for nonlinear macroscopic polarization in III-V nitride alloy heterostructures,” Appl. Phys. Lett. 80(7), 1204–1206 (2002).
    [CrossRef]

2013 (1)

W. Yang, D. Li, J. He, X. Hu, “Advantage of tapered and graded AlGaN electron blocking layer in InGaN-based blue laser diodes,” Phys. Status Solidi C 10(3), 346–349 (2013).
[CrossRef]

2012 (4)

W. Yang, D. Li, N. Liu, Z. Chen, L. Wang, L. Liu, L. Li, C. Wan, W. Chen, X. Hu, W. Du, “Improvement of hole injection and electron overflow by a tapered AlGaN electron blocking layer in InGaN-based laser diodes,” Appl. Phys. Lett. 100(3), 031105 (2012).
[CrossRef]

R. M. Farrell, E. C. Young, F. Wu, S. P. DenBaars, J. S. Speck, “Materials and growth issues for high-performance nonpolar and semipolar light-emitting devices,” Semicond. Sci. Technol. 27(2), 024001 (2012).
[CrossRef]

P. S. Hsu, M. T. Hardy, F. Wu, I. Koslow, E. C. Young, A. E. Romanov, K. Fujito, D. F. Feezell, S. P. DenBaars, J. S. Peck, S. Nakamura, “444.9 nm semipolar (112¯2) laser diode grown on an intentionally stress relaxed InGaN waveguiding layer,” Appl. Phys. Lett. 100, 021104 (2012).

J. Piprek, “Ultra-violet light-emitting diodes with quasi acceptor-free AlGaN polarization doping,” Opt. Quantum Electron. 44(3-5), 67–73 (2012).
[CrossRef]

2011 (3)

H. Zhao, G. 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(S4Suppl 4), A991–A1007 (2011).
[CrossRef] [PubMed]

P.-M. Tu, C.-Y. Chang, S.-C. Huang, C.-H. Chiu, J.-R. Chang, W.-T. Chang, D.-S. Wuu, H.-W. Zan, C.-C. Lin, H.-C. Kuo, C.-P. Hsu, “Investigation of efficiency droop for InGaN-based UV light-emitting diodes with InAlGaN barrier,” Appl. Phys. Lett. 98(21), 211107 (2011).
[CrossRef]

Y. Zhang, T.-T. Kao, J. Liu, Z. Lochner, S.-S. Kim, J.-H. Ryou, R. D. Dupuis, S.-C. Shen, “Effects of a step-graded AlxGa1-xN electron blocking layer in InGaN-based laser diodes,” J. Appl. Phys. 109(8), 083115 (2011).
[CrossRef]

2010 (5)

C. H. Wang, C. C. Ke, C. Y. Lee, S. P. Chang, W. T. Chang, J. C. Li, Z. Y. Li, H. C. Yang, H. C. Kuo, T. C. Lu, S. C. Wang, “Hole injection and efficiency droop improvement in InGaN/GaN light-emitting diodes by band-engineered electron blocking layer,” Appl. Phys. Lett. 97(26), 261103 (2010).
[CrossRef]

H. Zhao, G. Liu, R. A. Arif, N. Tansu, “Current injection efficiency induced efficiency-droop in InGaN quantum well light-emitting diodes,” Solid-State Electron. 54(10), 1119–1124 (2010).
[CrossRef]

C. H. Wang, J. R. Chen, C. H. Chiu, H. C. Kuo, Y. L. Li, T. C. Lu, S. C. Wang, “Temperature-dependent electroluminescence efficiency in blue InGaN–GaN light-emitting diodes with different well widths,” IEEE Photon. Technol. Lett. 22(4), 236–238 (2010).
[CrossRef]

A. David, M. J. Grundmann, “Droop in InGaN light-emitting diodes: A differential carrier lifetime analysis,” Appl. Phys. Lett. 96(10), 103504 (2010).
[CrossRef]

H. J. Kim, S. Choi, S.-S. Kim, J.-H. Ryou, P. D. Yoder, R. D. Dupuis, A. M. Fischer, K. Sun, F. A. Ponce, “Improvement of quantum efficiency by employing active-layer-friendly lattice-matched InAlN electron blocking layer in green light-emitting diodes,” Appl. Phys. Lett. 96(10), 101102 (2010).
[CrossRef]

2009 (3)

K. J. Vampola, M. Iza, S. Keller, S. P. DenBaars, S. Nakamura, “Measurement of electron overflow in 450 nm InGaN light-emitting diode structures,” Appl. Phys. Lett. 94(6), 061116 (2009).
[CrossRef]

Y.-K. Kuo, J.-Y. Chang, M.-C. Tasi, S.-H. Yen, “Advantages of blue InGaN multiple-quantum well light-emitting diodes with InGaN barriers,” Appl. Phys. Lett. 95(1), 011116 (2009).
[CrossRef]

Y.-K. Kuo, M.-C. Tasi, S.-H. Yen, “Numerical simulation of blue InGaN light-emitting diodes with polarization-matched AlGaInN electron-blocking layer and barrier layer,” Opt. Commun. 282(21), 4252–4255 (2009).
[CrossRef]

2008 (3)

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(4), 041102 (2008).
[CrossRef]

X. Ni, Q. Fan, R. Shimada, Ü. Özgür, H. Morkoç, “Reduction of efficiency droop in InGaN light emitting diodes by coupled quantum wells,” Appl. Phys. Lett. 93(17), 171113 (2008).
[CrossRef]

J.-R. Chen, C.-H. Lee, T.-S. Ko, Y.-A. Chang, T.-C. Lu, H.-C. Kuo, Y.-K. Kuo, S.-C. Wang, “Effects of built-in polarization and carrier overflow on InGaN quantum-well lasers with electron blocking layers,” J. Lightwave Technol. 26(3), 329–337 (2008).
[CrossRef]

2007 (3)

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(9), 091110 (2007).
[CrossRef]

B. Monemar, B. E. Sernelius, “Defect related issues in the “current roll-off” in InGaN based light emitting diodes,” Appl. Phys. Lett. 91(18), 181103 (2007).
[CrossRef]

M.-H. Kim, M. F. Schubert, Q. Dai, J. K. Kim, E. F. Schubert, J. Piprek, Y. Park, “Origin of efficiency droop in GaN-based light-emitting diodes,” Appl. Phys. Lett. 91(18), 183507 (2007).
[CrossRef]

2006 (1)

Y. Taniyasu, M. Kasu, T. Makimoto, “An aluminium nitride light-emitting diode with a wavelength of 210 nanometres,” Nature 441(7091), 325–328 (2006).
[CrossRef] [PubMed]

2003 (1)

I. Vurgaftman, J. R. Meyer, “Band parameters for nitrogen-containing semiconductors,” J. Appl. Phys. 94(6), 3675–3696 (2003).
[CrossRef]

2002 (1)

V. Fiorentini, F. Bernardini, O. Ambacher, “Evidence for nonlinear macroscopic polarization in III-V nitride alloy heterostructures,” Appl. Phys. Lett. 80(7), 1204–1206 (2002).
[CrossRef]

1995 (1)

S. Nakamura, M. Senoh, N. Iwsa, S.-I. Nagahama, “High-brightness InGaN blue, green and yellow light-emtting diodes with quantum well structures,” Jpn. J. Appl. Phys. 34(Part 2, No. 7A), L797–L799 (1995).
[CrossRef]

Ambacher, O.

V. Fiorentini, F. Bernardini, O. Ambacher, “Evidence for nonlinear macroscopic polarization in III-V nitride alloy heterostructures,” Appl. Phys. Lett. 80(7), 1204–1206 (2002).
[CrossRef]

Arif, R. A.

H. Zhao, G. Liu, R. A. Arif, N. Tansu, “Current injection efficiency induced efficiency-droop in InGaN quantum well light-emitting diodes,” Solid-State Electron. 54(10), 1119–1124 (2010).
[CrossRef]

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(9), 091110 (2007).
[CrossRef]

Bernardini, F.

V. Fiorentini, F. Bernardini, O. Ambacher, “Evidence for nonlinear macroscopic polarization in III-V nitride alloy heterostructures,” Appl. Phys. Lett. 80(7), 1204–1206 (2002).
[CrossRef]

Chang, C.-Y.

P.-M. Tu, C.-Y. Chang, S.-C. Huang, C.-H. Chiu, J.-R. Chang, W.-T. Chang, D.-S. Wuu, H.-W. Zan, C.-C. Lin, H.-C. Kuo, C.-P. Hsu, “Investigation of efficiency droop for InGaN-based UV light-emitting diodes with InAlGaN barrier,” Appl. Phys. Lett. 98(21), 211107 (2011).
[CrossRef]

Chang, J.-R.

P.-M. Tu, C.-Y. Chang, S.-C. Huang, C.-H. Chiu, J.-R. Chang, W.-T. Chang, D.-S. Wuu, H.-W. Zan, C.-C. Lin, H.-C. Kuo, C.-P. Hsu, “Investigation of efficiency droop for InGaN-based UV light-emitting diodes with InAlGaN barrier,” Appl. Phys. Lett. 98(21), 211107 (2011).
[CrossRef]

Chang, J.-Y.

Y.-K. Kuo, J.-Y. Chang, M.-C. Tasi, S.-H. Yen, “Advantages of blue InGaN multiple-quantum well light-emitting diodes with InGaN barriers,” Appl. Phys. Lett. 95(1), 011116 (2009).
[CrossRef]

Chang, S. P.

C. H. Wang, C. C. Ke, C. Y. Lee, S. P. Chang, W. T. Chang, J. C. Li, Z. Y. Li, H. C. Yang, H. C. Kuo, T. C. Lu, S. C. Wang, “Hole injection and efficiency droop improvement in InGaN/GaN light-emitting diodes by band-engineered electron blocking layer,” Appl. Phys. Lett. 97(26), 261103 (2010).
[CrossRef]

Chang, W. T.

C. H. Wang, C. C. Ke, C. Y. Lee, S. P. Chang, W. T. Chang, J. C. Li, Z. Y. Li, H. C. Yang, H. C. Kuo, T. C. Lu, S. C. Wang, “Hole injection and efficiency droop improvement in InGaN/GaN light-emitting diodes by band-engineered electron blocking layer,” Appl. Phys. Lett. 97(26), 261103 (2010).
[CrossRef]

Chang, W.-T.

P.-M. Tu, C.-Y. Chang, S.-C. Huang, C.-H. Chiu, J.-R. Chang, W.-T. Chang, D.-S. Wuu, H.-W. Zan, C.-C. Lin, H.-C. Kuo, C.-P. Hsu, “Investigation of efficiency droop for InGaN-based UV light-emitting diodes with InAlGaN barrier,” Appl. Phys. Lett. 98(21), 211107 (2011).
[CrossRef]

Chang, Y.-A.

Chen, J. R.

C. H. Wang, J. R. Chen, C. H. Chiu, H. C. Kuo, Y. L. Li, T. C. Lu, S. C. Wang, “Temperature-dependent electroluminescence efficiency in blue InGaN–GaN light-emitting diodes with different well widths,” IEEE Photon. Technol. Lett. 22(4), 236–238 (2010).
[CrossRef]

Chen, J.-R.

Chen, W.

W. Yang, D. Li, N. Liu, Z. Chen, L. Wang, L. Liu, L. Li, C. Wan, W. Chen, X. Hu, W. Du, “Improvement of hole injection and electron overflow by a tapered AlGaN electron blocking layer in InGaN-based laser diodes,” Appl. Phys. Lett. 100(3), 031105 (2012).
[CrossRef]

Chen, Z.

W. Yang, D. Li, N. Liu, Z. Chen, L. Wang, L. Liu, L. Li, C. Wan, W. Chen, X. Hu, W. Du, “Improvement of hole injection and electron overflow by a tapered AlGaN electron blocking layer in InGaN-based laser diodes,” Appl. Phys. Lett. 100(3), 031105 (2012).
[CrossRef]

Chiu, C. H.

C. H. Wang, J. R. Chen, C. H. Chiu, H. C. Kuo, Y. L. Li, T. C. Lu, S. C. Wang, “Temperature-dependent electroluminescence efficiency in blue InGaN–GaN light-emitting diodes with different well widths,” IEEE Photon. Technol. Lett. 22(4), 236–238 (2010).
[CrossRef]

Chiu, C.-H.

P.-M. Tu, C.-Y. Chang, S.-C. Huang, C.-H. Chiu, J.-R. Chang, W.-T. Chang, D.-S. Wuu, H.-W. Zan, C.-C. Lin, H.-C. Kuo, C.-P. Hsu, “Investigation of efficiency droop for InGaN-based UV light-emitting diodes with InAlGaN barrier,” Appl. Phys. Lett. 98(21), 211107 (2011).
[CrossRef]

Choi, S.

H. J. Kim, S. Choi, S.-S. Kim, J.-H. Ryou, P. D. Yoder, R. D. Dupuis, A. M. Fischer, K. Sun, F. A. Ponce, “Improvement of quantum efficiency by employing active-layer-friendly lattice-matched InAlN electron blocking layer in green light-emitting diodes,” Appl. Phys. Lett. 96(10), 101102 (2010).
[CrossRef]

Dai, Q.

M.-H. Kim, M. F. Schubert, Q. Dai, J. K. Kim, E. F. Schubert, J. Piprek, Y. Park, “Origin of efficiency droop in GaN-based light-emitting diodes,” Appl. Phys. Lett. 91(18), 183507 (2007).
[CrossRef]

David, A.

A. David, M. J. Grundmann, “Droop in InGaN light-emitting diodes: A differential carrier lifetime analysis,” Appl. Phys. Lett. 96(10), 103504 (2010).
[CrossRef]

DenBaars, S. P.

R. M. Farrell, E. C. Young, F. Wu, S. P. DenBaars, J. S. Speck, “Materials and growth issues for high-performance nonpolar and semipolar light-emitting devices,” Semicond. Sci. Technol. 27(2), 024001 (2012).
[CrossRef]

P. S. Hsu, M. T. Hardy, F. Wu, I. Koslow, E. C. Young, A. E. Romanov, K. Fujito, D. F. Feezell, S. P. DenBaars, J. S. Peck, S. Nakamura, “444.9 nm semipolar (112¯2) laser diode grown on an intentionally stress relaxed InGaN waveguiding layer,” Appl. Phys. Lett. 100, 021104 (2012).

K. J. Vampola, M. Iza, S. Keller, S. P. DenBaars, S. Nakamura, “Measurement of electron overflow in 450 nm InGaN light-emitting diode structures,” Appl. Phys. Lett. 94(6), 061116 (2009).
[CrossRef]

Dierolf, V.

Du, W.

W. Yang, D. Li, N. Liu, Z. Chen, L. Wang, L. Liu, L. Li, C. Wan, W. Chen, X. Hu, W. Du, “Improvement of hole injection and electron overflow by a tapered AlGaN electron blocking layer in InGaN-based laser diodes,” Appl. Phys. Lett. 100(3), 031105 (2012).
[CrossRef]

Dupuis, R. D.

Y. Zhang, T.-T. Kao, J. Liu, Z. Lochner, S.-S. Kim, J.-H. Ryou, R. D. Dupuis, S.-C. Shen, “Effects of a step-graded AlxGa1-xN electron blocking layer in InGaN-based laser diodes,” J. Appl. Phys. 109(8), 083115 (2011).
[CrossRef]

H. J. Kim, S. Choi, S.-S. Kim, J.-H. Ryou, P. D. Yoder, R. D. Dupuis, A. M. Fischer, K. Sun, F. A. Ponce, “Improvement of quantum efficiency by employing active-layer-friendly lattice-matched InAlN electron blocking layer in green light-emitting diodes,” Appl. Phys. Lett. 96(10), 101102 (2010).
[CrossRef]

Ee, Y.-K.

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(9), 091110 (2007).
[CrossRef]

Fan, Q.

X. Ni, Q. Fan, R. Shimada, Ü. Özgür, H. Morkoç, “Reduction of efficiency droop in InGaN light emitting diodes by coupled quantum wells,” Appl. Phys. Lett. 93(17), 171113 (2008).
[CrossRef]

Farrell, R. M.

R. M. Farrell, E. C. Young, F. Wu, S. P. DenBaars, J. S. Speck, “Materials and growth issues for high-performance nonpolar and semipolar light-emitting devices,” Semicond. Sci. Technol. 27(2), 024001 (2012).
[CrossRef]

Feezell, D. F.

P. S. Hsu, M. T. Hardy, F. Wu, I. Koslow, E. C. Young, A. E. Romanov, K. Fujito, D. F. Feezell, S. P. DenBaars, J. S. Peck, S. Nakamura, “444.9 nm semipolar (112¯2) laser diode grown on an intentionally stress relaxed InGaN waveguiding layer,” Appl. Phys. Lett. 100, 021104 (2012).

Fiorentini, V.

V. Fiorentini, F. Bernardini, O. Ambacher, “Evidence for nonlinear macroscopic polarization in III-V nitride alloy heterostructures,” Appl. Phys. Lett. 80(7), 1204–1206 (2002).
[CrossRef]

Fischer, A. M.

H. J. Kim, S. Choi, S.-S. Kim, J.-H. Ryou, P. D. Yoder, R. D. Dupuis, A. M. Fischer, K. Sun, F. A. Ponce, “Improvement of quantum efficiency by employing active-layer-friendly lattice-matched InAlN electron blocking layer in green light-emitting diodes,” Appl. Phys. Lett. 96(10), 101102 (2010).
[CrossRef]

Fujito, K.

P. S. Hsu, M. T. Hardy, F. Wu, I. Koslow, E. C. Young, A. E. Romanov, K. Fujito, D. F. Feezell, S. P. DenBaars, J. S. Peck, S. Nakamura, “444.9 nm semipolar (112¯2) laser diode grown on an intentionally stress relaxed InGaN waveguiding layer,” Appl. Phys. Lett. 100, 021104 (2012).

Grundmann, M. J.

A. David, M. J. Grundmann, “Droop in InGaN light-emitting diodes: A differential carrier lifetime analysis,” Appl. Phys. Lett. 96(10), 103504 (2010).
[CrossRef]

Hardy, M. T.

P. S. Hsu, M. T. Hardy, F. Wu, I. Koslow, E. C. Young, A. E. Romanov, K. Fujito, D. F. Feezell, S. P. DenBaars, J. S. Peck, S. Nakamura, “444.9 nm semipolar (112¯2) laser diode grown on an intentionally stress relaxed InGaN waveguiding layer,” Appl. Phys. Lett. 100, 021104 (2012).

He, J.

W. Yang, D. Li, J. He, X. Hu, “Advantage of tapered and graded AlGaN electron blocking layer in InGaN-based blue laser diodes,” Phys. Status Solidi C 10(3), 346–349 (2013).
[CrossRef]

Hsu, C.-P.

P.-M. Tu, C.-Y. Chang, S.-C. Huang, C.-H. Chiu, J.-R. Chang, W.-T. Chang, D.-S. Wuu, H.-W. Zan, C.-C. Lin, H.-C. Kuo, C.-P. Hsu, “Investigation of efficiency droop for InGaN-based UV light-emitting diodes with InAlGaN barrier,” Appl. Phys. Lett. 98(21), 211107 (2011).
[CrossRef]

Hsu, P. S.

P. S. Hsu, M. T. Hardy, F. Wu, I. Koslow, E. C. Young, A. E. Romanov, K. Fujito, D. F. Feezell, S. P. DenBaars, J. S. Peck, S. Nakamura, “444.9 nm semipolar (112¯2) laser diode grown on an intentionally stress relaxed InGaN waveguiding layer,” Appl. Phys. Lett. 100, 021104 (2012).

Hu, X.

W. Yang, D. Li, J. He, X. Hu, “Advantage of tapered and graded AlGaN electron blocking layer in InGaN-based blue laser diodes,” Phys. Status Solidi C 10(3), 346–349 (2013).
[CrossRef]

W. Yang, D. Li, N. Liu, Z. Chen, L. Wang, L. Liu, L. Li, C. Wan, W. Chen, X. Hu, W. Du, “Improvement of hole injection and electron overflow by a tapered AlGaN electron blocking layer in InGaN-based laser diodes,” Appl. Phys. Lett. 100(3), 031105 (2012).
[CrossRef]

Huang, S.-C.

P.-M. Tu, C.-Y. Chang, S.-C. Huang, C.-H. Chiu, J.-R. Chang, W.-T. Chang, D.-S. Wuu, H.-W. Zan, C.-C. Lin, H.-C. Kuo, C.-P. Hsu, “Investigation of efficiency droop for InGaN-based UV light-emitting diodes with InAlGaN barrier,” Appl. Phys. Lett. 98(21), 211107 (2011).
[CrossRef]

Iwsa, N.

S. Nakamura, M. Senoh, N. Iwsa, S.-I. Nagahama, “High-brightness InGaN blue, green and yellow light-emtting diodes with quantum well structures,” Jpn. J. Appl. Phys. 34(Part 2, No. 7A), L797–L799 (1995).
[CrossRef]

Iza, M.

K. J. Vampola, M. Iza, S. Keller, S. P. DenBaars, S. Nakamura, “Measurement of electron overflow in 450 nm InGaN light-emitting diode structures,” Appl. Phys. Lett. 94(6), 061116 (2009).
[CrossRef]

Kao, T.-T.

Y. Zhang, T.-T. Kao, J. Liu, Z. Lochner, S.-S. Kim, J.-H. Ryou, R. D. Dupuis, S.-C. Shen, “Effects of a step-graded AlxGa1-xN electron blocking layer in InGaN-based laser diodes,” J. Appl. Phys. 109(8), 083115 (2011).
[CrossRef]

Kasu, M.

Y. Taniyasu, M. Kasu, T. Makimoto, “An aluminium nitride light-emitting diode with a wavelength of 210 nanometres,” Nature 441(7091), 325–328 (2006).
[CrossRef] [PubMed]

Ke, C. C.

C. H. Wang, C. C. Ke, C. Y. Lee, S. P. Chang, W. T. Chang, J. C. Li, Z. Y. Li, H. C. Yang, H. C. Kuo, T. C. Lu, S. C. Wang, “Hole injection and efficiency droop improvement in InGaN/GaN light-emitting diodes by band-engineered electron blocking layer,” Appl. Phys. Lett. 97(26), 261103 (2010).
[CrossRef]

Keller, S.

K. J. Vampola, M. Iza, S. Keller, S. P. DenBaars, S. Nakamura, “Measurement of electron overflow in 450 nm InGaN light-emitting diode structures,” Appl. Phys. Lett. 94(6), 061116 (2009).
[CrossRef]

Kim, H. J.

H. J. Kim, S. Choi, S.-S. Kim, J.-H. Ryou, P. D. Yoder, R. D. Dupuis, A. M. Fischer, K. Sun, F. A. Ponce, “Improvement of quantum efficiency by employing active-layer-friendly lattice-matched InAlN electron blocking layer in green light-emitting diodes,” Appl. Phys. Lett. 96(10), 101102 (2010).
[CrossRef]

Kim, J. K.

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(4), 041102 (2008).
[CrossRef]

M.-H. Kim, M. F. Schubert, Q. Dai, J. K. Kim, E. F. Schubert, J. Piprek, Y. Park, “Origin of efficiency droop in GaN-based light-emitting diodes,” Appl. Phys. Lett. 91(18), 183507 (2007).
[CrossRef]

Kim, M. H.

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(4), 041102 (2008).
[CrossRef]

Kim, M.-H.

M.-H. Kim, M. F. Schubert, Q. Dai, J. K. Kim, E. F. Schubert, J. Piprek, Y. Park, “Origin of efficiency droop in GaN-based light-emitting diodes,” Appl. Phys. Lett. 91(18), 183507 (2007).
[CrossRef]

Kim, S.-S.

Y. Zhang, T.-T. Kao, J. Liu, Z. Lochner, S.-S. Kim, J.-H. Ryou, R. D. Dupuis, S.-C. Shen, “Effects of a step-graded AlxGa1-xN electron blocking layer in InGaN-based laser diodes,” J. Appl. Phys. 109(8), 083115 (2011).
[CrossRef]

H. J. Kim, S. Choi, S.-S. Kim, J.-H. Ryou, P. D. Yoder, R. D. Dupuis, A. M. Fischer, K. Sun, F. A. Ponce, “Improvement of quantum efficiency by employing active-layer-friendly lattice-matched InAlN electron blocking layer in green light-emitting diodes,” Appl. Phys. Lett. 96(10), 101102 (2010).
[CrossRef]

Ko, T.-S.

Koslow, I.

P. S. Hsu, M. T. Hardy, F. Wu, I. Koslow, E. C. Young, A. E. Romanov, K. Fujito, D. F. Feezell, S. P. DenBaars, J. S. Peck, S. Nakamura, “444.9 nm semipolar (112¯2) laser diode grown on an intentionally stress relaxed InGaN waveguiding layer,” Appl. Phys. Lett. 100, 021104 (2012).

Kuo, H. C.

C. H. Wang, J. R. Chen, C. H. Chiu, H. C. Kuo, Y. L. Li, T. C. Lu, S. C. Wang, “Temperature-dependent electroluminescence efficiency in blue InGaN–GaN light-emitting diodes with different well widths,” IEEE Photon. Technol. Lett. 22(4), 236–238 (2010).
[CrossRef]

C. H. Wang, C. C. Ke, C. Y. Lee, S. P. Chang, W. T. Chang, J. C. Li, Z. Y. Li, H. C. Yang, H. C. Kuo, T. C. Lu, S. C. Wang, “Hole injection and efficiency droop improvement in InGaN/GaN light-emitting diodes by band-engineered electron blocking layer,” Appl. Phys. Lett. 97(26), 261103 (2010).
[CrossRef]

Kuo, H.-C.

P.-M. Tu, C.-Y. Chang, S.-C. Huang, C.-H. Chiu, J.-R. Chang, W.-T. Chang, D.-S. Wuu, H.-W. Zan, C.-C. Lin, H.-C. Kuo, C.-P. Hsu, “Investigation of efficiency droop for InGaN-based UV light-emitting diodes with InAlGaN barrier,” Appl. Phys. Lett. 98(21), 211107 (2011).
[CrossRef]

J.-R. Chen, C.-H. Lee, T.-S. Ko, Y.-A. Chang, T.-C. Lu, H.-C. Kuo, Y.-K. Kuo, S.-C. Wang, “Effects of built-in polarization and carrier overflow on InGaN quantum-well lasers with electron blocking layers,” J. Lightwave Technol. 26(3), 329–337 (2008).
[CrossRef]

Kuo, Y.-K.

Y.-K. Kuo, J.-Y. Chang, M.-C. Tasi, S.-H. Yen, “Advantages of blue InGaN multiple-quantum well light-emitting diodes with InGaN barriers,” Appl. Phys. Lett. 95(1), 011116 (2009).
[CrossRef]

Y.-K. Kuo, M.-C. Tasi, S.-H. Yen, “Numerical simulation of blue InGaN light-emitting diodes with polarization-matched AlGaInN electron-blocking layer and barrier layer,” Opt. Commun. 282(21), 4252–4255 (2009).
[CrossRef]

J.-R. Chen, C.-H. Lee, T.-S. Ko, Y.-A. Chang, T.-C. Lu, H.-C. Kuo, Y.-K. Kuo, S.-C. Wang, “Effects of built-in polarization and carrier overflow on InGaN quantum-well lasers with electron blocking layers,” J. Lightwave Technol. 26(3), 329–337 (2008).
[CrossRef]

Lee, C. Y.

C. H. Wang, C. C. Ke, C. Y. Lee, S. P. Chang, W. T. Chang, J. C. Li, Z. Y. Li, H. C. Yang, H. C. Kuo, T. C. Lu, S. C. Wang, “Hole injection and efficiency droop improvement in InGaN/GaN light-emitting diodes by band-engineered electron blocking layer,” Appl. Phys. Lett. 97(26), 261103 (2010).
[CrossRef]

Lee, C.-H.

Lee, S. M.

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(4), 041102 (2008).
[CrossRef]

Li, D.

W. Yang, D. Li, J. He, X. Hu, “Advantage of tapered and graded AlGaN electron blocking layer in InGaN-based blue laser diodes,” Phys. Status Solidi C 10(3), 346–349 (2013).
[CrossRef]

W. Yang, D. Li, N. Liu, Z. Chen, L. Wang, L. Liu, L. Li, C. Wan, W. Chen, X. Hu, W. Du, “Improvement of hole injection and electron overflow by a tapered AlGaN electron blocking layer in InGaN-based laser diodes,” Appl. Phys. Lett. 100(3), 031105 (2012).
[CrossRef]

Li, J. C.

C. H. Wang, C. C. Ke, C. Y. Lee, S. P. Chang, W. T. Chang, J. C. Li, Z. Y. Li, H. C. Yang, H. C. Kuo, T. C. Lu, S. C. Wang, “Hole injection and efficiency droop improvement in InGaN/GaN light-emitting diodes by band-engineered electron blocking layer,” Appl. Phys. Lett. 97(26), 261103 (2010).
[CrossRef]

Li, L.

W. Yang, D. Li, N. Liu, Z. Chen, L. Wang, L. Liu, L. Li, C. Wan, W. Chen, X. Hu, W. Du, “Improvement of hole injection and electron overflow by a tapered AlGaN electron blocking layer in InGaN-based laser diodes,” Appl. Phys. Lett. 100(3), 031105 (2012).
[CrossRef]

Li, Y. L.

C. H. Wang, J. R. Chen, C. H. Chiu, H. C. Kuo, Y. L. Li, T. C. Lu, S. C. Wang, “Temperature-dependent electroluminescence efficiency in blue InGaN–GaN light-emitting diodes with different well widths,” IEEE Photon. Technol. Lett. 22(4), 236–238 (2010).
[CrossRef]

Li, Z. Y.

C. H. Wang, C. C. Ke, C. Y. Lee, S. P. Chang, W. T. Chang, J. C. Li, Z. Y. Li, H. C. Yang, H. C. Kuo, T. C. Lu, S. C. Wang, “Hole injection and efficiency droop improvement in InGaN/GaN light-emitting diodes by band-engineered electron blocking layer,” Appl. Phys. Lett. 97(26), 261103 (2010).
[CrossRef]

Lin, C.-C.

P.-M. Tu, C.-Y. Chang, S.-C. Huang, C.-H. Chiu, J.-R. Chang, W.-T. Chang, D.-S. Wuu, H.-W. Zan, C.-C. Lin, H.-C. Kuo, C.-P. Hsu, “Investigation of efficiency droop for InGaN-based UV light-emitting diodes with InAlGaN barrier,” Appl. Phys. Lett. 98(21), 211107 (2011).
[CrossRef]

Liu, G.

H. Zhao, G. 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(S4Suppl 4), A991–A1007 (2011).
[CrossRef] [PubMed]

H. Zhao, G. Liu, R. A. Arif, N. Tansu, “Current injection efficiency induced efficiency-droop in InGaN quantum well light-emitting diodes,” Solid-State Electron. 54(10), 1119–1124 (2010).
[CrossRef]

Liu, J.

Y. Zhang, T.-T. Kao, J. Liu, Z. Lochner, S.-S. Kim, J.-H. Ryou, R. D. Dupuis, S.-C. Shen, “Effects of a step-graded AlxGa1-xN electron blocking layer in InGaN-based laser diodes,” J. Appl. Phys. 109(8), 083115 (2011).
[CrossRef]

Liu, L.

W. Yang, D. Li, N. Liu, Z. Chen, L. Wang, L. Liu, L. Li, C. Wan, W. Chen, X. Hu, W. Du, “Improvement of hole injection and electron overflow by a tapered AlGaN electron blocking layer in InGaN-based laser diodes,” Appl. Phys. Lett. 100(3), 031105 (2012).
[CrossRef]

Liu, N.

W. Yang, D. Li, N. Liu, Z. Chen, L. Wang, L. Liu, L. Li, C. Wan, W. Chen, X. Hu, W. Du, “Improvement of hole injection and electron overflow by a tapered AlGaN electron blocking layer in InGaN-based laser diodes,” Appl. Phys. Lett. 100(3), 031105 (2012).
[CrossRef]

Lochner, Z.

Y. Zhang, T.-T. Kao, J. Liu, Z. Lochner, S.-S. Kim, J.-H. Ryou, R. D. Dupuis, S.-C. Shen, “Effects of a step-graded AlxGa1-xN electron blocking layer in InGaN-based laser diodes,” J. Appl. Phys. 109(8), 083115 (2011).
[CrossRef]

Lu, T. C.

C. H. Wang, C. C. Ke, C. Y. Lee, S. P. Chang, W. T. Chang, J. C. Li, Z. Y. Li, H. C. Yang, H. C. Kuo, T. C. Lu, S. C. Wang, “Hole injection and efficiency droop improvement in InGaN/GaN light-emitting diodes by band-engineered electron blocking layer,” Appl. Phys. Lett. 97(26), 261103 (2010).
[CrossRef]

C. H. Wang, J. R. Chen, C. H. Chiu, H. C. Kuo, Y. L. Li, T. C. Lu, S. C. Wang, “Temperature-dependent electroluminescence efficiency in blue InGaN–GaN light-emitting diodes with different well widths,” IEEE Photon. Technol. Lett. 22(4), 236–238 (2010).
[CrossRef]

Lu, T.-C.

Makimoto, T.

Y. Taniyasu, M. Kasu, T. Makimoto, “An aluminium nitride light-emitting diode with a wavelength of 210 nanometres,” Nature 441(7091), 325–328 (2006).
[CrossRef] [PubMed]

Meyer, J. R.

I. Vurgaftman, J. R. Meyer, “Band parameters for nitrogen-containing semiconductors,” J. Appl. Phys. 94(6), 3675–3696 (2003).
[CrossRef]

Monemar, B.

B. Monemar, B. E. Sernelius, “Defect related issues in the “current roll-off” in InGaN based light emitting diodes,” Appl. Phys. Lett. 91(18), 181103 (2007).
[CrossRef]

Morkoç, H.

X. Ni, Q. Fan, R. Shimada, Ü. Özgür, H. Morkoç, “Reduction of efficiency droop in InGaN light emitting diodes by coupled quantum wells,” Appl. Phys. Lett. 93(17), 171113 (2008).
[CrossRef]

Nagahama, S.-I.

S. Nakamura, M. Senoh, N. Iwsa, S.-I. Nagahama, “High-brightness InGaN blue, green and yellow light-emtting diodes with quantum well structures,” Jpn. J. Appl. Phys. 34(Part 2, No. 7A), L797–L799 (1995).
[CrossRef]

Nakamura, S.

P. S. Hsu, M. T. Hardy, F. Wu, I. Koslow, E. C. Young, A. E. Romanov, K. Fujito, D. F. Feezell, S. P. DenBaars, J. S. Peck, S. Nakamura, “444.9 nm semipolar (112¯2) laser diode grown on an intentionally stress relaxed InGaN waveguiding layer,” Appl. Phys. Lett. 100, 021104 (2012).

K. J. Vampola, M. Iza, S. Keller, S. P. DenBaars, S. Nakamura, “Measurement of electron overflow in 450 nm InGaN light-emitting diode structures,” Appl. Phys. Lett. 94(6), 061116 (2009).
[CrossRef]

S. Nakamura, M. Senoh, N. Iwsa, S.-I. Nagahama, “High-brightness InGaN blue, green and yellow light-emtting diodes with quantum well structures,” Jpn. J. Appl. Phys. 34(Part 2, No. 7A), L797–L799 (1995).
[CrossRef]

J. Piprek, S. Nakamura, “Physics of high-power InGaN/GaN lasers,” in Proceedings of IEE Conference on Optoelectron. (2002), pp. 145–151.
[CrossRef]

Ni, X.

X. Ni, Q. Fan, R. Shimada, Ü. Özgür, H. Morkoç, “Reduction of efficiency droop in InGaN light emitting diodes by coupled quantum wells,” Appl. Phys. Lett. 93(17), 171113 (2008).
[CrossRef]

Özgür, Ü.

X. Ni, Q. Fan, R. Shimada, Ü. Özgür, H. Morkoç, “Reduction of efficiency droop in InGaN light emitting diodes by coupled quantum wells,” Appl. Phys. Lett. 93(17), 171113 (2008).
[CrossRef]

Park, Y.

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(4), 041102 (2008).
[CrossRef]

M.-H. Kim, M. F. Schubert, Q. Dai, J. K. Kim, E. F. Schubert, J. Piprek, Y. Park, “Origin of efficiency droop in GaN-based light-emitting diodes,” Appl. Phys. Lett. 91(18), 183507 (2007).
[CrossRef]

Peck, J. S.

P. S. Hsu, M. T. Hardy, F. Wu, I. Koslow, E. C. Young, A. E. Romanov, K. Fujito, D. F. Feezell, S. P. DenBaars, J. S. Peck, S. Nakamura, “444.9 nm semipolar (112¯2) laser diode grown on an intentionally stress relaxed InGaN waveguiding layer,” Appl. Phys. Lett. 100, 021104 (2012).

Piprek, J.

J. Piprek, “Ultra-violet light-emitting diodes with quasi acceptor-free AlGaN polarization doping,” Opt. Quantum Electron. 44(3-5), 67–73 (2012).
[CrossRef]

M.-H. Kim, M. F. Schubert, Q. Dai, J. K. Kim, E. F. Schubert, J. Piprek, Y. Park, “Origin of efficiency droop in GaN-based light-emitting diodes,” Appl. Phys. Lett. 91(18), 183507 (2007).
[CrossRef]

J. Piprek, S. Nakamura, “Physics of high-power InGaN/GaN lasers,” in Proceedings of IEE Conference on Optoelectron. (2002), pp. 145–151.
[CrossRef]

Ponce, F. A.

H. J. Kim, S. Choi, S.-S. Kim, J.-H. Ryou, P. D. Yoder, R. D. Dupuis, A. M. Fischer, K. Sun, F. A. Ponce, “Improvement of quantum efficiency by employing active-layer-friendly lattice-matched InAlN electron blocking layer in green light-emitting diodes,” Appl. Phys. Lett. 96(10), 101102 (2010).
[CrossRef]

Poplawsky, J. D.

Romanov, A. E.

P. S. Hsu, M. T. Hardy, F. Wu, I. Koslow, E. C. Young, A. E. Romanov, K. Fujito, D. F. Feezell, S. P. DenBaars, J. S. Peck, S. Nakamura, “444.9 nm semipolar (112¯2) laser diode grown on an intentionally stress relaxed InGaN waveguiding layer,” Appl. Phys. Lett. 100, 021104 (2012).

Ryou, J.-H.

Y. Zhang, T.-T. Kao, J. Liu, Z. Lochner, S.-S. Kim, J.-H. Ryou, R. D. Dupuis, S.-C. Shen, “Effects of a step-graded AlxGa1-xN electron blocking layer in InGaN-based laser diodes,” J. Appl. Phys. 109(8), 083115 (2011).
[CrossRef]

H. J. Kim, S. Choi, S.-S. Kim, J.-H. Ryou, P. D. Yoder, R. D. Dupuis, A. M. Fischer, K. Sun, F. A. Ponce, “Improvement of quantum efficiency by employing active-layer-friendly lattice-matched InAlN electron blocking layer in green light-emitting diodes,” Appl. Phys. Lett. 96(10), 101102 (2010).
[CrossRef]

Sakong, T.

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(4), 041102 (2008).
[CrossRef]

Schubert, E. F.

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(4), 041102 (2008).
[CrossRef]

M.-H. Kim, M. F. Schubert, Q. Dai, J. K. Kim, E. F. Schubert, J. Piprek, Y. Park, “Origin of efficiency droop in GaN-based light-emitting diodes,” Appl. Phys. Lett. 91(18), 183507 (2007).
[CrossRef]

Schubert, M. F.

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(4), 041102 (2008).
[CrossRef]

M.-H. Kim, M. F. Schubert, Q. Dai, J. K. Kim, E. F. Schubert, J. Piprek, Y. Park, “Origin of efficiency droop in GaN-based light-emitting diodes,” Appl. Phys. Lett. 91(18), 183507 (2007).
[CrossRef]

Senoh, M.

S. Nakamura, M. Senoh, N. Iwsa, S.-I. Nagahama, “High-brightness InGaN blue, green and yellow light-emtting diodes with quantum well structures,” Jpn. J. Appl. Phys. 34(Part 2, No. 7A), L797–L799 (1995).
[CrossRef]

Sernelius, B. E.

B. Monemar, B. E. Sernelius, “Defect related issues in the “current roll-off” in InGaN based light emitting diodes,” Appl. Phys. Lett. 91(18), 181103 (2007).
[CrossRef]

Shen, S.-C.

Y. Zhang, T.-T. Kao, J. Liu, Z. Lochner, S.-S. Kim, J.-H. Ryou, R. D. Dupuis, S.-C. Shen, “Effects of a step-graded AlxGa1-xN electron blocking layer in InGaN-based laser diodes,” J. Appl. Phys. 109(8), 083115 (2011).
[CrossRef]

Shimada, R.

X. Ni, Q. Fan, R. Shimada, Ü. Özgür, H. Morkoç, “Reduction of efficiency droop in InGaN light emitting diodes by coupled quantum wells,” Appl. Phys. Lett. 93(17), 171113 (2008).
[CrossRef]

Sone, C.

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(4), 041102 (2008).
[CrossRef]

Speck, J. S.

R. M. Farrell, E. C. Young, F. Wu, S. P. DenBaars, J. S. Speck, “Materials and growth issues for high-performance nonpolar and semipolar light-emitting devices,” Semicond. Sci. Technol. 27(2), 024001 (2012).
[CrossRef]

Sun, K.

H. J. Kim, S. Choi, S.-S. Kim, J.-H. Ryou, P. D. Yoder, R. D. Dupuis, A. M. Fischer, K. Sun, F. A. Ponce, “Improvement of quantum efficiency by employing active-layer-friendly lattice-matched InAlN electron blocking layer in green light-emitting diodes,” Appl. Phys. Lett. 96(10), 101102 (2010).
[CrossRef]

Taniyasu, Y.

Y. Taniyasu, M. Kasu, T. Makimoto, “An aluminium nitride light-emitting diode with a wavelength of 210 nanometres,” Nature 441(7091), 325–328 (2006).
[CrossRef] [PubMed]

Tansu, N.

H. Zhao, G. 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(S4Suppl 4), A991–A1007 (2011).
[CrossRef] [PubMed]

H. Zhao, G. Liu, R. A. Arif, N. Tansu, “Current injection efficiency induced efficiency-droop in InGaN quantum well light-emitting diodes,” Solid-State Electron. 54(10), 1119–1124 (2010).
[CrossRef]

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(9), 091110 (2007).
[CrossRef]

Tasi, M.-C.

Y.-K. Kuo, M.-C. Tasi, S.-H. Yen, “Numerical simulation of blue InGaN light-emitting diodes with polarization-matched AlGaInN electron-blocking layer and barrier layer,” Opt. Commun. 282(21), 4252–4255 (2009).
[CrossRef]

Y.-K. Kuo, J.-Y. Chang, M.-C. Tasi, S.-H. Yen, “Advantages of blue InGaN multiple-quantum well light-emitting diodes with InGaN barriers,” Appl. Phys. Lett. 95(1), 011116 (2009).
[CrossRef]

Tu, P.-M.

P.-M. Tu, C.-Y. Chang, S.-C. Huang, C.-H. Chiu, J.-R. Chang, W.-T. Chang, D.-S. Wuu, H.-W. Zan, C.-C. Lin, H.-C. Kuo, C.-P. Hsu, “Investigation of efficiency droop for InGaN-based UV light-emitting diodes with InAlGaN barrier,” Appl. Phys. Lett. 98(21), 211107 (2011).
[CrossRef]

Vampola, K. J.

K. J. Vampola, M. Iza, S. Keller, S. P. DenBaars, S. Nakamura, “Measurement of electron overflow in 450 nm InGaN light-emitting diode structures,” Appl. Phys. Lett. 94(6), 061116 (2009).
[CrossRef]

Vurgaftman, I.

I. Vurgaftman, J. R. Meyer, “Band parameters for nitrogen-containing semiconductors,” J. Appl. Phys. 94(6), 3675–3696 (2003).
[CrossRef]

Wan, C.

W. Yang, D. Li, N. Liu, Z. Chen, L. Wang, L. Liu, L. Li, C. Wan, W. Chen, X. Hu, W. Du, “Improvement of hole injection and electron overflow by a tapered AlGaN electron blocking layer in InGaN-based laser diodes,” Appl. Phys. Lett. 100(3), 031105 (2012).
[CrossRef]

Wang, C. H.

C. H. Wang, J. R. Chen, C. H. Chiu, H. C. Kuo, Y. L. Li, T. C. Lu, S. C. Wang, “Temperature-dependent electroluminescence efficiency in blue InGaN–GaN light-emitting diodes with different well widths,” IEEE Photon. Technol. Lett. 22(4), 236–238 (2010).
[CrossRef]

C. H. Wang, C. C. Ke, C. Y. Lee, S. P. Chang, W. T. Chang, J. C. Li, Z. Y. Li, H. C. Yang, H. C. Kuo, T. C. Lu, S. C. Wang, “Hole injection and efficiency droop improvement in InGaN/GaN light-emitting diodes by band-engineered electron blocking layer,” Appl. Phys. Lett. 97(26), 261103 (2010).
[CrossRef]

Wang, L.

W. Yang, D. Li, N. Liu, Z. Chen, L. Wang, L. Liu, L. Li, C. Wan, W. Chen, X. Hu, W. Du, “Improvement of hole injection and electron overflow by a tapered AlGaN electron blocking layer in InGaN-based laser diodes,” Appl. Phys. Lett. 100(3), 031105 (2012).
[CrossRef]

Wang, S. C.

C. H. Wang, J. R. Chen, C. H. Chiu, H. C. Kuo, Y. L. Li, T. C. Lu, S. C. Wang, “Temperature-dependent electroluminescence efficiency in blue InGaN–GaN light-emitting diodes with different well widths,” IEEE Photon. Technol. Lett. 22(4), 236–238 (2010).
[CrossRef]

C. H. Wang, C. C. Ke, C. Y. Lee, S. P. Chang, W. T. Chang, J. C. Li, Z. Y. Li, H. C. Yang, H. C. Kuo, T. C. Lu, S. C. Wang, “Hole injection and efficiency droop improvement in InGaN/GaN light-emitting diodes by band-engineered electron blocking layer,” Appl. Phys. Lett. 97(26), 261103 (2010).
[CrossRef]

Wang, S.-C.

Wu, F.

P. S. Hsu, M. T. Hardy, F. Wu, I. Koslow, E. C. Young, A. E. Romanov, K. Fujito, D. F. Feezell, S. P. DenBaars, J. S. Peck, S. Nakamura, “444.9 nm semipolar (112¯2) laser diode grown on an intentionally stress relaxed InGaN waveguiding layer,” Appl. Phys. Lett. 100, 021104 (2012).

R. M. Farrell, E. C. Young, F. Wu, S. P. DenBaars, J. S. Speck, “Materials and growth issues for high-performance nonpolar and semipolar light-emitting devices,” Semicond. Sci. Technol. 27(2), 024001 (2012).
[CrossRef]

Wuu, D.-S.

P.-M. Tu, C.-Y. Chang, S.-C. Huang, C.-H. Chiu, J.-R. Chang, W.-T. Chang, D.-S. Wuu, H.-W. Zan, C.-C. Lin, H.-C. Kuo, C.-P. Hsu, “Investigation of efficiency droop for InGaN-based UV light-emitting diodes with InAlGaN barrier,” Appl. Phys. Lett. 98(21), 211107 (2011).
[CrossRef]

Xu, J.

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(4), 041102 (2008).
[CrossRef]

Yang, H. C.

C. H. Wang, C. C. Ke, C. Y. Lee, S. P. Chang, W. T. Chang, J. C. Li, Z. Y. Li, H. C. Yang, H. C. Kuo, T. C. Lu, S. C. Wang, “Hole injection and efficiency droop improvement in InGaN/GaN light-emitting diodes by band-engineered electron blocking layer,” Appl. Phys. Lett. 97(26), 261103 (2010).
[CrossRef]

Yang, W.

W. Yang, D. Li, J. He, X. Hu, “Advantage of tapered and graded AlGaN electron blocking layer in InGaN-based blue laser diodes,” Phys. Status Solidi C 10(3), 346–349 (2013).
[CrossRef]

W. Yang, D. Li, N. Liu, Z. Chen, L. Wang, L. Liu, L. Li, C. Wan, W. Chen, X. Hu, W. Du, “Improvement of hole injection and electron overflow by a tapered AlGaN electron blocking layer in InGaN-based laser diodes,” Appl. Phys. Lett. 100(3), 031105 (2012).
[CrossRef]

Yen, S.-H.

Y.-K. Kuo, M.-C. Tasi, S.-H. Yen, “Numerical simulation of blue InGaN light-emitting diodes with polarization-matched AlGaInN electron-blocking layer and barrier layer,” Opt. Commun. 282(21), 4252–4255 (2009).
[CrossRef]

Y.-K. Kuo, J.-Y. Chang, M.-C. Tasi, S.-H. Yen, “Advantages of blue InGaN multiple-quantum well light-emitting diodes with InGaN barriers,” Appl. Phys. Lett. 95(1), 011116 (2009).
[CrossRef]

Yoder, P. D.

H. J. Kim, S. Choi, S.-S. Kim, J.-H. Ryou, P. D. Yoder, R. D. Dupuis, A. M. Fischer, K. Sun, F. A. Ponce, “Improvement of quantum efficiency by employing active-layer-friendly lattice-matched InAlN electron blocking layer in green light-emitting diodes,” Appl. Phys. Lett. 96(10), 101102 (2010).
[CrossRef]

Yoon, S.

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(4), 041102 (2008).
[CrossRef]

Young, E. C.

R. M. Farrell, E. C. Young, F. Wu, S. P. DenBaars, J. S. Speck, “Materials and growth issues for high-performance nonpolar and semipolar light-emitting devices,” Semicond. Sci. Technol. 27(2), 024001 (2012).
[CrossRef]

P. S. Hsu, M. T. Hardy, F. Wu, I. Koslow, E. C. Young, A. E. Romanov, K. Fujito, D. F. Feezell, S. P. DenBaars, J. S. Peck, S. Nakamura, “444.9 nm semipolar (112¯2) laser diode grown on an intentionally stress relaxed InGaN waveguiding layer,” Appl. Phys. Lett. 100, 021104 (2012).

Zan, H.-W.

P.-M. Tu, C.-Y. Chang, S.-C. Huang, C.-H. Chiu, J.-R. Chang, W.-T. Chang, D.-S. Wuu, H.-W. Zan, C.-C. Lin, H.-C. Kuo, C.-P. Hsu, “Investigation of efficiency droop for InGaN-based UV light-emitting diodes with InAlGaN barrier,” Appl. Phys. Lett. 98(21), 211107 (2011).
[CrossRef]

Zhang, J.

Zhang, Y.

Y. Zhang, T.-T. Kao, J. Liu, Z. Lochner, S.-S. Kim, J.-H. Ryou, R. D. Dupuis, S.-C. Shen, “Effects of a step-graded AlxGa1-xN electron blocking layer in InGaN-based laser diodes,” J. Appl. Phys. 109(8), 083115 (2011).
[CrossRef]

Zhao, H.

H. Zhao, G. 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(S4Suppl 4), A991–A1007 (2011).
[CrossRef] [PubMed]

H. Zhao, G. Liu, R. A. Arif, N. Tansu, “Current injection efficiency induced efficiency-droop in InGaN quantum well light-emitting diodes,” Solid-State Electron. 54(10), 1119–1124 (2010).
[CrossRef]

Appl. Phys. Lett. (14)

P. S. Hsu, M. T. Hardy, F. Wu, I. Koslow, E. C. Young, A. E. Romanov, K. Fujito, D. F. Feezell, S. P. DenBaars, J. S. Peck, S. Nakamura, “444.9 nm semipolar (112¯2) laser diode grown on an intentionally stress relaxed InGaN waveguiding layer,” Appl. Phys. Lett. 100, 021104 (2012).

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(4), 041102 (2008).
[CrossRef]

P.-M. Tu, C.-Y. Chang, S.-C. Huang, C.-H. Chiu, J.-R. Chang, W.-T. Chang, D.-S. Wuu, H.-W. Zan, C.-C. Lin, H.-C. Kuo, C.-P. Hsu, “Investigation of efficiency droop for InGaN-based UV light-emitting diodes with InAlGaN barrier,” Appl. Phys. Lett. 98(21), 211107 (2011).
[CrossRef]

Y.-K. Kuo, J.-Y. Chang, M.-C. Tasi, S.-H. Yen, “Advantages of blue InGaN multiple-quantum well light-emitting diodes with InGaN barriers,” Appl. Phys. Lett. 95(1), 011116 (2009).
[CrossRef]

C. H. Wang, C. C. Ke, C. Y. Lee, S. P. Chang, W. T. Chang, J. C. Li, Z. Y. Li, H. C. Yang, H. C. Kuo, T. C. Lu, S. C. Wang, “Hole injection and efficiency droop improvement in InGaN/GaN light-emitting diodes by band-engineered electron blocking layer,” Appl. Phys. Lett. 97(26), 261103 (2010).
[CrossRef]

W. Yang, D. Li, N. Liu, Z. Chen, L. Wang, L. Liu, L. Li, C. Wan, W. Chen, X. Hu, W. Du, “Improvement of hole injection and electron overflow by a tapered AlGaN electron blocking layer in InGaN-based laser diodes,” Appl. Phys. Lett. 100(3), 031105 (2012).
[CrossRef]

A. David, M. J. Grundmann, “Droop in InGaN light-emitting diodes: A differential carrier lifetime analysis,” Appl. Phys. Lett. 96(10), 103504 (2010).
[CrossRef]

B. Monemar, B. E. Sernelius, “Defect related issues in the “current roll-off” in InGaN based light emitting diodes,” Appl. Phys. Lett. 91(18), 181103 (2007).
[CrossRef]

X. Ni, Q. Fan, R. Shimada, Ü. Özgür, H. Morkoç, “Reduction of efficiency droop in InGaN light emitting diodes by coupled quantum wells,” Appl. Phys. Lett. 93(17), 171113 (2008).
[CrossRef]

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(9), 091110 (2007).
[CrossRef]

H. J. Kim, S. Choi, S.-S. Kim, J.-H. Ryou, P. D. Yoder, R. D. Dupuis, A. M. Fischer, K. Sun, F. A. Ponce, “Improvement of quantum efficiency by employing active-layer-friendly lattice-matched InAlN electron blocking layer in green light-emitting diodes,” Appl. Phys. Lett. 96(10), 101102 (2010).
[CrossRef]

V. Fiorentini, F. Bernardini, O. Ambacher, “Evidence for nonlinear macroscopic polarization in III-V nitride alloy heterostructures,” Appl. Phys. Lett. 80(7), 1204–1206 (2002).
[CrossRef]

M.-H. Kim, M. F. Schubert, Q. Dai, J. K. Kim, E. F. Schubert, J. Piprek, Y. Park, “Origin of efficiency droop in GaN-based light-emitting diodes,” Appl. Phys. Lett. 91(18), 183507 (2007).
[CrossRef]

K. J. Vampola, M. Iza, S. Keller, S. P. DenBaars, S. Nakamura, “Measurement of electron overflow in 450 nm InGaN light-emitting diode structures,” Appl. Phys. Lett. 94(6), 061116 (2009).
[CrossRef]

IEEE Photon. Technol. Lett. (1)

C. H. Wang, J. R. Chen, C. H. Chiu, H. C. Kuo, Y. L. Li, T. C. Lu, S. C. Wang, “Temperature-dependent electroluminescence efficiency in blue InGaN–GaN light-emitting diodes with different well widths,” IEEE Photon. Technol. Lett. 22(4), 236–238 (2010).
[CrossRef]

J. Appl. Phys. (2)

Y. Zhang, T.-T. Kao, J. Liu, Z. Lochner, S.-S. Kim, J.-H. Ryou, R. D. Dupuis, S.-C. Shen, “Effects of a step-graded AlxGa1-xN electron blocking layer in InGaN-based laser diodes,” J. Appl. Phys. 109(8), 083115 (2011).
[CrossRef]

I. Vurgaftman, J. R. Meyer, “Band parameters for nitrogen-containing semiconductors,” J. Appl. Phys. 94(6), 3675–3696 (2003).
[CrossRef]

J. Lightwave Technol. (1)

Jpn. J. Appl. Phys. (1)

S. Nakamura, M. Senoh, N. Iwsa, S.-I. Nagahama, “High-brightness InGaN blue, green and yellow light-emtting diodes with quantum well structures,” Jpn. J. Appl. Phys. 34(Part 2, No. 7A), L797–L799 (1995).
[CrossRef]

Nature (1)

Y. Taniyasu, M. Kasu, T. Makimoto, “An aluminium nitride light-emitting diode with a wavelength of 210 nanometres,” Nature 441(7091), 325–328 (2006).
[CrossRef] [PubMed]

Opt. Commun. (1)

Y.-K. Kuo, M.-C. Tasi, S.-H. Yen, “Numerical simulation of blue InGaN light-emitting diodes with polarization-matched AlGaInN electron-blocking layer and barrier layer,” Opt. Commun. 282(21), 4252–4255 (2009).
[CrossRef]

Opt. Express (1)

Opt. Quantum Electron. (1)

J. Piprek, “Ultra-violet light-emitting diodes with quasi acceptor-free AlGaN polarization doping,” Opt. Quantum Electron. 44(3-5), 67–73 (2012).
[CrossRef]

Phys. Status Solidi C (1)

W. Yang, D. Li, J. He, X. Hu, “Advantage of tapered and graded AlGaN electron blocking layer in InGaN-based blue laser diodes,” Phys. Status Solidi C 10(3), 346–349 (2013).
[CrossRef]

Semicond. Sci. Technol. (1)

R. M. Farrell, E. C. Young, F. Wu, S. P. DenBaars, J. S. Speck, “Materials and growth issues for high-performance nonpolar and semipolar light-emitting devices,” Semicond. Sci. Technol. 27(2), 024001 (2012).
[CrossRef]

Solid-State Electron. (1)

H. Zhao, G. Liu, R. A. Arif, N. Tansu, “Current injection efficiency induced efficiency-droop in InGaN quantum well light-emitting diodes,” Solid-State Electron. 54(10), 1119–1124 (2010).
[CrossRef]

Other (2)

APSYS by Crosslight Software Inc, Burnaby, Canada, http://www.crosslight.com .

J. Piprek, S. Nakamura, “Physics of high-power InGaN/GaN lasers,” in Proceedings of IEE Conference on Optoelectron. (2002), pp. 145–151.
[CrossRef]

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Figures (6)

Fig. 1
Fig. 1

(a) Energy band diagram of the original LED at 200 mA. (b) Enlarged drawing of the conduction band near the last-QB/EBL interface. (c) Enlarged drawing of the valance band near the last-QB/EBL interface.

Fig. 2
Fig. 2

Electrostatic fields near the last two QWs and EBL for original and tapered EBL LEDs at 200 mA.

Fig. 3
Fig. 3

Enlarged energy band diagrams near the last-QB/EBL interface of tapered EBL LED in (a) the conduction band (b) the valance band at 200 mA.

Fig. 4
Fig. 4

(a) Electron and (b) hole concentrations within the active regions for original and tapered EBL LEDs at 200 mA.

Fig. 5
Fig. 5

(a) Electron current density profiles near the active regions and (b) hole transmitting probability near the last QB and EBL for original and tapered EBL LEDs.

Fig. 6
Fig. 6

Experiment and simulation external quantum efficiency for original and tapered EBL LEDs.

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