Abstract

The enhanced light output power of a InGaN/AlGaN-based light-emitting diodes (LEDs) using three different types of highly reflective Sn-doped indium oxide (ITO)/Al-based p-type reflectors, namely, ITO/Al, Cu-doped indium oxide (CIO)/s-ITO(sputtered)/Al, and Ag nano-dots(n-Ag)/CIO/s-ITO/Al, is presented. The ITO/Al-based reflectors exhibit lower reflectance (76 - 84% at 365 nm) than Al only reflector (91.1%). However, unlike Al only n-type contact, the ITO/Al-based contacts to p-GaN show good ohmic characteristics. Near-UV (365 nm) InGaN/AlGaN-based LEDs with ITO/Al, CIO/s-ITO/Al, and n-Ag/CIO/s-ITO/Al reflectors exhibit forward-bias voltages of 3.55, 3.48, and 3.34 V at 20 mA, respectively. The LEDs with the ITO/Al and CIO/s-ITO/Al reflectors exhibit 9.5% and 13.5% higher light output power (at 20 mA), respectively, than the LEDs with the n-Ag/CIO/s-ITO/Al reflector. The improved performance of near UV LEDs is attributed to the high reflectance and low contact resistivity of the ITO/Al-based reflectors, which are better than those of conventional Al-based reflectors.

© 2013 Optical Society of America

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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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2012 (1)

K. Takehara, K. Takeda, S. Ito, H. Aoshima, M. Iwaya, T. Takeuchi, S. Kamiyama, I. Akasaki, and H. Amano, “Indium-tin oxide/Al reflective electrodes for ultraviolet light-emitting diodes,” Jpn. J. Appl. Phys.51, 042101 (2012).
[CrossRef]

2011 (2)

W. H. Lee, D. J. Chae, D. Y. Kim, and T. G. Kim, “Improved electrical and optical properties of vertical GaN LEDs using fluorine-doped ITO/Al ohmic reflectors,” IEEE J. Quantum Electron.47(10), 1277–1282 (2011).
[CrossRef]

I.-C. Chen, Y.-D. Chen, C.-C. Hsieh, C.-H. Kuo, and L.-C. Chang, “Highly reflective Ag/La bilayer ohmic contacts to p-type GaN,” J. Electrochem. Soc.158(3), H285–H288 (2011).
[CrossRef]

2010 (2)

J.-O. Song, J.-S. Ha, and T.-Y. Seong, “Ohmic-contact technology for GaN-based light-emitting diodes: role of P-type contact,” IEEE Trans. Electron. Dev.57(1), 42–59 (2010).
[CrossRef]

N. Lobo, H. Rodriguez, A. Knauer, M. Hoppe, S. Einfeldt, P. Vogt, M. Weyers, and M. Kneissl, “Enhancement of light extraction in ultraviolet light-emitting diodes using nanopixel contact design with Al reflector,” Appl. Phys. Lett.96(8), 081109 (2010).
[CrossRef]

2009 (1)

H. Tsuzuki, F. Mori, K. Takeda, M. Iwaya, S. Kamiyama, H. Amano, I. Akasaki, H. Yoshida, M. Kuwabara, Y. Yamashita, and H. Kan, “Novel UV devices on high-quality AlGaN using grooved underlying layer,” J. Cryst. Growth311(10), 2860–2863 (2009).
[CrossRef]

2008 (1)

2007 (1)

H. Kim, K. H. Baik, J. Cho, J. W. Lee, S. Yoon, H. Kim, S. N. Lee, C. Sone, Y. Park, and T.-Y. Seong, “High-reflectance and thermally stable AgCu alloy p-type reflectors for GaN-based light-emitting diodes,” IEEE Photon. Technol. Lett.19(5), 336–338 (2007).
[CrossRef]

2006 (1)

M. Kneissl, Z. Yang, M. Teepe, C. Knollenberg, N. M. Johnson, A. Usikov, and V. Dmitriev, “Ultraviolet InAlGaN light emitting diodes grown on hydride vapor phase epitaxy AlGaN/sapphire templates,” Jpn. J. Appl. Phys.45(5A), 3905–3908 (2006).
[CrossRef]

2005 (2)

J.-O. Song, W.-G. Hong, J. S. Kwak, Y. Park, and T.-Y. Seong, “Low-resistance Al-based reflectors for high-power GaN-based flip-chip light-emitting diodes,” Appl. Phys. Lett.86(13), 133503 (2005).
[CrossRef]

J.-O. Song, S. Kwak, Y. Park, and T.-Y. Seong, “Improvement of the light output of InGaN-based light-emitting diodes using Cu-doped indium oxide/indium tin oxide p-type electrodes,” Appl. Phys. Lett.86(21), 213505 (2005).
[CrossRef]

2004 (4)

H. W. Jang and J.-L. Lee, “Mechanism for ohmic contact formation of Ni/Ag contacts on p-type GaN,” Appl. Phys. Lett.85(24), 5920–5922 (2004).
[CrossRef]

W. Sun, V. Adivarahan, M. Shatalov, Y. Lee, S. Wu, J. Yang, J. Zhang, and M. A. Khan, “Continuous wave milliwatt power AlGaN light emitting diodes at 280 nm,” Jpn. J. Appl. Phys.43(No. 11A), L1419–L1421 (2004).
[CrossRef]

J. I. Sohn, J.-O. Song, D.-S. Leem, S. Lee, and T.-Y. Seong, “Formation of nonalloyed low resistance Ni/Au ohmic contacts to p-type GaN using Au nano-dots,” Electrochem. Solid-State Lett.7(9), G179–G181 (2004).
[CrossRef]

J.-O. Song and T.-Y. Seong, “Highly transparent Ag/SnO2 ohmic contact to p-type GaN for ultraviolet light-emitting diodes,” Appl. Phys. Lett.85(26), 6374–6376 (2004).
[CrossRef]

2003 (2)

J.-O. Song, D.-S. Leem, J. S. Kwak, O. H. Nam, Y. Park, and T.-Y. Seong, “Low-resistance and highly-reflective Zn-Ni solid solution/Ag ohmic contacts for flip-chip light-emitting diodes,” Appl. Phys. Lett.83(24), 4990–4992 (2003).
[CrossRef]

D. L. Hibbard, S. P. Jung, C. Wang, D. Ullery, Y. S. Zhao, H. P. Lee, W. So, and H. Liu, “Low resistance high reflectance contacts to p-GaN using oxidized Ni/Au and Al or Ag,” Appl. Phys. Lett.83(2), 311–313 (2003).
[CrossRef]

2002 (1)

S. K. Lee, C. M. Zettering, M. Ostling, I. Aberg, M. H. Magnusson, K. Deppert, L. E. Wernersson, L. Samuelson, and A. Litwin, “Reduction of the Schottky barrier height on silicon carbide using Au nano-particles,” Solid-State Electron.46(9), 1433–1440 (2002).
[CrossRef]

1997 (1)

B. P. Luther, J. M. DeLucca, S. E. Mohney, and R. F. Karlicek., “Analysis of a thin AlN interfacial layer in Ti/Al and Pd/Al ohmic contacts to n-type GaN,” Appl. Phys. Lett.71(26), 3859–3861 (1997).
[CrossRef]

1992 (1)

R. T. Tung, “Electron transport at metal-semiconductor interfaces: General theory,” Phys. Rev. B Condens. Matter45(23), 13509–13523 (1992).
[CrossRef] [PubMed]

Aberg, I.

S. K. Lee, C. M. Zettering, M. Ostling, I. Aberg, M. H. Magnusson, K. Deppert, L. E. Wernersson, L. Samuelson, and A. Litwin, “Reduction of the Schottky barrier height on silicon carbide using Au nano-particles,” Solid-State Electron.46(9), 1433–1440 (2002).
[CrossRef]

Adivarahan, V.

W. Sun, V. Adivarahan, M. Shatalov, Y. Lee, S. Wu, J. Yang, J. Zhang, and M. A. Khan, “Continuous wave milliwatt power AlGaN light emitting diodes at 280 nm,” Jpn. J. Appl. Phys.43(No. 11A), L1419–L1421 (2004).
[CrossRef]

Akasaki, I.

K. Takehara, K. Takeda, S. Ito, H. Aoshima, M. Iwaya, T. Takeuchi, S. Kamiyama, I. Akasaki, and H. Amano, “Indium-tin oxide/Al reflective electrodes for ultraviolet light-emitting diodes,” Jpn. J. Appl. Phys.51, 042101 (2012).
[CrossRef]

H. Tsuzuki, F. Mori, K. Takeda, M. Iwaya, S. Kamiyama, H. Amano, I. Akasaki, H. Yoshida, M. Kuwabara, Y. Yamashita, and H. Kan, “Novel UV devices on high-quality AlGaN using grooved underlying layer,” J. Cryst. Growth311(10), 2860–2863 (2009).
[CrossRef]

Amano, H.

K. Takehara, K. Takeda, S. Ito, H. Aoshima, M. Iwaya, T. Takeuchi, S. Kamiyama, I. Akasaki, and H. Amano, “Indium-tin oxide/Al reflective electrodes for ultraviolet light-emitting diodes,” Jpn. J. Appl. Phys.51, 042101 (2012).
[CrossRef]

H. Tsuzuki, F. Mori, K. Takeda, M. Iwaya, S. Kamiyama, H. Amano, I. Akasaki, H. Yoshida, M. Kuwabara, Y. Yamashita, and H. Kan, “Novel UV devices on high-quality AlGaN using grooved underlying layer,” J. Cryst. Growth311(10), 2860–2863 (2009).
[CrossRef]

Aoshima, H.

K. Takehara, K. Takeda, S. Ito, H. Aoshima, M. Iwaya, T. Takeuchi, S. Kamiyama, I. Akasaki, and H. Amano, “Indium-tin oxide/Al reflective electrodes for ultraviolet light-emitting diodes,” Jpn. J. Appl. Phys.51, 042101 (2012).
[CrossRef]

Baik, K. H.

H. Kim, K. H. Baik, J. Cho, J. W. Lee, S. Yoon, H. Kim, S. N. Lee, C. Sone, Y. Park, and T.-Y. Seong, “High-reflectance and thermally stable AgCu alloy p-type reflectors for GaN-based light-emitting diodes,” IEEE Photon. Technol. Lett.19(5), 336–338 (2007).
[CrossRef]

Chae, D. J.

W. H. Lee, D. J. Chae, D. Y. Kim, and T. G. Kim, “Improved electrical and optical properties of vertical GaN LEDs using fluorine-doped ITO/Al ohmic reflectors,” IEEE J. Quantum Electron.47(10), 1277–1282 (2011).
[CrossRef]

Chang, L.-C.

I.-C. Chen, Y.-D. Chen, C.-C. Hsieh, C.-H. Kuo, and L.-C. Chang, “Highly reflective Ag/La bilayer ohmic contacts to p-type GaN,” J. Electrochem. Soc.158(3), H285–H288 (2011).
[CrossRef]

Chen, I.-C.

I.-C. Chen, Y.-D. Chen, C.-C. Hsieh, C.-H. Kuo, and L.-C. Chang, “Highly reflective Ag/La bilayer ohmic contacts to p-type GaN,” J. Electrochem. Soc.158(3), H285–H288 (2011).
[CrossRef]

Chen, Y.-D.

I.-C. Chen, Y.-D. Chen, C.-C. Hsieh, C.-H. Kuo, and L.-C. Chang, “Highly reflective Ag/La bilayer ohmic contacts to p-type GaN,” J. Electrochem. Soc.158(3), H285–H288 (2011).
[CrossRef]

Cho, J.

H. Kim, K. H. Baik, J. Cho, J. W. Lee, S. Yoon, H. Kim, S. N. Lee, C. Sone, Y. Park, and T.-Y. Seong, “High-reflectance and thermally stable AgCu alloy p-type reflectors for GaN-based light-emitting diodes,” IEEE Photon. Technol. Lett.19(5), 336–338 (2007).
[CrossRef]

DeLucca, J. M.

B. P. Luther, J. M. DeLucca, S. E. Mohney, and R. F. Karlicek., “Analysis of a thin AlN interfacial layer in Ti/Al and Pd/Al ohmic contacts to n-type GaN,” Appl. Phys. Lett.71(26), 3859–3861 (1997).
[CrossRef]

Deppert, K.

S. K. Lee, C. M. Zettering, M. Ostling, I. Aberg, M. H. Magnusson, K. Deppert, L. E. Wernersson, L. Samuelson, and A. Litwin, “Reduction of the Schottky barrier height on silicon carbide using Au nano-particles,” Solid-State Electron.46(9), 1433–1440 (2002).
[CrossRef]

Dmitriev, V.

M. Kneissl, Z. Yang, M. Teepe, C. Knollenberg, N. M. Johnson, A. Usikov, and V. Dmitriev, “Ultraviolet InAlGaN light emitting diodes grown on hydride vapor phase epitaxy AlGaN/sapphire templates,” Jpn. J. Appl. Phys.45(5A), 3905–3908 (2006).
[CrossRef]

Einfeldt, S.

N. Lobo, H. Rodriguez, A. Knauer, M. Hoppe, S. Einfeldt, P. Vogt, M. Weyers, and M. Kneissl, “Enhancement of light extraction in ultraviolet light-emitting diodes using nanopixel contact design with Al reflector,” Appl. Phys. Lett.96(8), 081109 (2010).
[CrossRef]

Ha, J.-S.

J.-O. Song, J.-S. Ha, and T.-Y. Seong, “Ohmic-contact technology for GaN-based light-emitting diodes: role of P-type contact,” IEEE Trans. Electron. Dev.57(1), 42–59 (2010).
[CrossRef]

Hibbard, D. L.

D. L. Hibbard, S. P. Jung, C. Wang, D. Ullery, Y. S. Zhao, H. P. Lee, W. So, and H. Liu, “Low resistance high reflectance contacts to p-GaN using oxidized Ni/Au and Al or Ag,” Appl. Phys. Lett.83(2), 311–313 (2003).
[CrossRef]

Hong, W.-G.

J.-O. Song, W.-G. Hong, J. S. Kwak, Y. Park, and T.-Y. Seong, “Low-resistance Al-based reflectors for high-power GaN-based flip-chip light-emitting diodes,” Appl. Phys. Lett.86(13), 133503 (2005).
[CrossRef]

Hoppe, M.

N. Lobo, H. Rodriguez, A. Knauer, M. Hoppe, S. Einfeldt, P. Vogt, M. Weyers, and M. Kneissl, “Enhancement of light extraction in ultraviolet light-emitting diodes using nanopixel contact design with Al reflector,” Appl. Phys. Lett.96(8), 081109 (2010).
[CrossRef]

Hsieh, C.-C.

I.-C. Chen, Y.-D. Chen, C.-C. Hsieh, C.-H. Kuo, and L.-C. Chang, “Highly reflective Ag/La bilayer ohmic contacts to p-type GaN,” J. Electrochem. Soc.158(3), H285–H288 (2011).
[CrossRef]

Ito, S.

K. Takehara, K. Takeda, S. Ito, H. Aoshima, M. Iwaya, T. Takeuchi, S. Kamiyama, I. Akasaki, and H. Amano, “Indium-tin oxide/Al reflective electrodes for ultraviolet light-emitting diodes,” Jpn. J. Appl. Phys.51, 042101 (2012).
[CrossRef]

Iwaya, M.

K. Takehara, K. Takeda, S. Ito, H. Aoshima, M. Iwaya, T. Takeuchi, S. Kamiyama, I. Akasaki, and H. Amano, “Indium-tin oxide/Al reflective electrodes for ultraviolet light-emitting diodes,” Jpn. J. Appl. Phys.51, 042101 (2012).
[CrossRef]

H. Tsuzuki, F. Mori, K. Takeda, M. Iwaya, S. Kamiyama, H. Amano, I. Akasaki, H. Yoshida, M. Kuwabara, Y. Yamashita, and H. Kan, “Novel UV devices on high-quality AlGaN using grooved underlying layer,” J. Cryst. Growth311(10), 2860–2863 (2009).
[CrossRef]

Jang, H. W.

H. W. Jang and J.-L. Lee, “Mechanism for ohmic contact formation of Ni/Ag contacts on p-type GaN,” Appl. Phys. Lett.85(24), 5920–5922 (2004).
[CrossRef]

Johnson, N. M.

M. Kneissl, Z. Yang, M. Teepe, C. Knollenberg, N. M. Johnson, A. Usikov, and V. Dmitriev, “Ultraviolet InAlGaN light emitting diodes grown on hydride vapor phase epitaxy AlGaN/sapphire templates,” Jpn. J. Appl. Phys.45(5A), 3905–3908 (2006).
[CrossRef]

Jung, G. H.

Jung, S. P.

D. L. Hibbard, S. P. Jung, C. Wang, D. Ullery, Y. S. Zhao, H. P. Lee, W. So, and H. Liu, “Low resistance high reflectance contacts to p-GaN using oxidized Ni/Au and Al or Ag,” Appl. Phys. Lett.83(2), 311–313 (2003).
[CrossRef]

Kamiyama, S.

K. Takehara, K. Takeda, S. Ito, H. Aoshima, M. Iwaya, T. Takeuchi, S. Kamiyama, I. Akasaki, and H. Amano, “Indium-tin oxide/Al reflective electrodes for ultraviolet light-emitting diodes,” Jpn. J. Appl. Phys.51, 042101 (2012).
[CrossRef]

H. Tsuzuki, F. Mori, K. Takeda, M. Iwaya, S. Kamiyama, H. Amano, I. Akasaki, H. Yoshida, M. Kuwabara, Y. Yamashita, and H. Kan, “Novel UV devices on high-quality AlGaN using grooved underlying layer,” J. Cryst. Growth311(10), 2860–2863 (2009).
[CrossRef]

Kan, H.

H. Tsuzuki, F. Mori, K. Takeda, M. Iwaya, S. Kamiyama, H. Amano, I. Akasaki, H. Yoshida, M. Kuwabara, Y. Yamashita, and H. Kan, “Novel UV devices on high-quality AlGaN using grooved underlying layer,” J. Cryst. Growth311(10), 2860–2863 (2009).
[CrossRef]

Karlicek, R. F.

B. P. Luther, J. M. DeLucca, S. E. Mohney, and R. F. Karlicek., “Analysis of a thin AlN interfacial layer in Ti/Al and Pd/Al ohmic contacts to n-type GaN,” Appl. Phys. Lett.71(26), 3859–3861 (1997).
[CrossRef]

Khan, M. A.

W. Sun, V. Adivarahan, M. Shatalov, Y. Lee, S. Wu, J. Yang, J. Zhang, and M. A. Khan, “Continuous wave milliwatt power AlGaN light emitting diodes at 280 nm,” Jpn. J. Appl. Phys.43(No. 11A), L1419–L1421 (2004).
[CrossRef]

Kim, D. Y.

W. H. Lee, D. J. Chae, D. Y. Kim, and T. G. Kim, “Improved electrical and optical properties of vertical GaN LEDs using fluorine-doped ITO/Al ohmic reflectors,” IEEE J. Quantum Electron.47(10), 1277–1282 (2011).
[CrossRef]

Kim, H.

H. Kim, K. H. Baik, J. Cho, J. W. Lee, S. Yoon, H. Kim, S. N. Lee, C. Sone, Y. Park, and T.-Y. Seong, “High-reflectance and thermally stable AgCu alloy p-type reflectors for GaN-based light-emitting diodes,” IEEE Photon. Technol. Lett.19(5), 336–338 (2007).
[CrossRef]

H. Kim, K. H. Baik, J. Cho, J. W. Lee, S. Yoon, H. Kim, S. N. Lee, C. Sone, Y. Park, and T.-Y. Seong, “High-reflectance and thermally stable AgCu alloy p-type reflectors for GaN-based light-emitting diodes,” IEEE Photon. Technol. Lett.19(5), 336–338 (2007).
[CrossRef]

Kim, T. G.

W. H. Lee, D. J. Chae, D. Y. Kim, and T. G. Kim, “Improved electrical and optical properties of vertical GaN LEDs using fluorine-doped ITO/Al ohmic reflectors,” IEEE J. Quantum Electron.47(10), 1277–1282 (2011).
[CrossRef]

Knauer, A.

N. Lobo, H. Rodriguez, A. Knauer, M. Hoppe, S. Einfeldt, P. Vogt, M. Weyers, and M. Kneissl, “Enhancement of light extraction in ultraviolet light-emitting diodes using nanopixel contact design with Al reflector,” Appl. Phys. Lett.96(8), 081109 (2010).
[CrossRef]

Kneissl, M.

N. Lobo, H. Rodriguez, A. Knauer, M. Hoppe, S. Einfeldt, P. Vogt, M. Weyers, and M. Kneissl, “Enhancement of light extraction in ultraviolet light-emitting diodes using nanopixel contact design with Al reflector,” Appl. Phys. Lett.96(8), 081109 (2010).
[CrossRef]

M. Kneissl, Z. Yang, M. Teepe, C. Knollenberg, N. M. Johnson, A. Usikov, and V. Dmitriev, “Ultraviolet InAlGaN light emitting diodes grown on hydride vapor phase epitaxy AlGaN/sapphire templates,” Jpn. J. Appl. Phys.45(5A), 3905–3908 (2006).
[CrossRef]

Knollenberg, C.

M. Kneissl, Z. Yang, M. Teepe, C. Knollenberg, N. M. Johnson, A. Usikov, and V. Dmitriev, “Ultraviolet InAlGaN light emitting diodes grown on hydride vapor phase epitaxy AlGaN/sapphire templates,” Jpn. J. Appl. Phys.45(5A), 3905–3908 (2006).
[CrossRef]

Kuo, C.-H.

I.-C. Chen, Y.-D. Chen, C.-C. Hsieh, C.-H. Kuo, and L.-C. Chang, “Highly reflective Ag/La bilayer ohmic contacts to p-type GaN,” J. Electrochem. Soc.158(3), H285–H288 (2011).
[CrossRef]

Kuwabara, M.

H. Tsuzuki, F. Mori, K. Takeda, M. Iwaya, S. Kamiyama, H. Amano, I. Akasaki, H. Yoshida, M. Kuwabara, Y. Yamashita, and H. Kan, “Novel UV devices on high-quality AlGaN using grooved underlying layer,” J. Cryst. Growth311(10), 2860–2863 (2009).
[CrossRef]

Kwak, J. S.

J.-O. Song, W.-G. Hong, J. S. Kwak, Y. Park, and T.-Y. Seong, “Low-resistance Al-based reflectors for high-power GaN-based flip-chip light-emitting diodes,” Appl. Phys. Lett.86(13), 133503 (2005).
[CrossRef]

J.-O. Song, D.-S. Leem, J. S. Kwak, O. H. Nam, Y. Park, and T.-Y. Seong, “Low-resistance and highly-reflective Zn-Ni solid solution/Ag ohmic contacts for flip-chip light-emitting diodes,” Appl. Phys. Lett.83(24), 4990–4992 (2003).
[CrossRef]

Kwak, S.

J.-O. Song, S. Kwak, Y. Park, and T.-Y. Seong, “Improvement of the light output of InGaN-based light-emitting diodes using Cu-doped indium oxide/indium tin oxide p-type electrodes,” Appl. Phys. Lett.86(21), 213505 (2005).
[CrossRef]

Lee, H. P.

D. L. Hibbard, S. P. Jung, C. Wang, D. Ullery, Y. S. Zhao, H. P. Lee, W. So, and H. Liu, “Low resistance high reflectance contacts to p-GaN using oxidized Ni/Au and Al or Ag,” Appl. Phys. Lett.83(2), 311–313 (2003).
[CrossRef]

Lee, J. W.

H. Kim, K. H. Baik, J. Cho, J. W. Lee, S. Yoon, H. Kim, S. N. Lee, C. Sone, Y. Park, and T.-Y. Seong, “High-reflectance and thermally stable AgCu alloy p-type reflectors for GaN-based light-emitting diodes,” IEEE Photon. Technol. Lett.19(5), 336–338 (2007).
[CrossRef]

Lee, J.-L.

J. H. Son, G. H. Jung, and J.-L. Lee, “Highly reflective Ag-Cu alloy-based ohmic contact on p-type GaN using Ru overlayer,” Opt. Lett.33(24), 2907–2909 (2008).
[CrossRef] [PubMed]

H. W. Jang and J.-L. Lee, “Mechanism for ohmic contact formation of Ni/Ag contacts on p-type GaN,” Appl. Phys. Lett.85(24), 5920–5922 (2004).
[CrossRef]

Lee, S.

J. I. Sohn, J.-O. Song, D.-S. Leem, S. Lee, and T.-Y. Seong, “Formation of nonalloyed low resistance Ni/Au ohmic contacts to p-type GaN using Au nano-dots,” Electrochem. Solid-State Lett.7(9), G179–G181 (2004).
[CrossRef]

Lee, S. K.

S. K. Lee, C. M. Zettering, M. Ostling, I. Aberg, M. H. Magnusson, K. Deppert, L. E. Wernersson, L. Samuelson, and A. Litwin, “Reduction of the Schottky barrier height on silicon carbide using Au nano-particles,” Solid-State Electron.46(9), 1433–1440 (2002).
[CrossRef]

Lee, S. N.

H. Kim, K. H. Baik, J. Cho, J. W. Lee, S. Yoon, H. Kim, S. N. Lee, C. Sone, Y. Park, and T.-Y. Seong, “High-reflectance and thermally stable AgCu alloy p-type reflectors for GaN-based light-emitting diodes,” IEEE Photon. Technol. Lett.19(5), 336–338 (2007).
[CrossRef]

Lee, W. H.

W. H. Lee, D. J. Chae, D. Y. Kim, and T. G. Kim, “Improved electrical and optical properties of vertical GaN LEDs using fluorine-doped ITO/Al ohmic reflectors,” IEEE J. Quantum Electron.47(10), 1277–1282 (2011).
[CrossRef]

Lee, Y.

W. Sun, V. Adivarahan, M. Shatalov, Y. Lee, S. Wu, J. Yang, J. Zhang, and M. A. Khan, “Continuous wave milliwatt power AlGaN light emitting diodes at 280 nm,” Jpn. J. Appl. Phys.43(No. 11A), L1419–L1421 (2004).
[CrossRef]

Leem, D.-S.

J. I. Sohn, J.-O. Song, D.-S. Leem, S. Lee, and T.-Y. Seong, “Formation of nonalloyed low resistance Ni/Au ohmic contacts to p-type GaN using Au nano-dots,” Electrochem. Solid-State Lett.7(9), G179–G181 (2004).
[CrossRef]

J.-O. Song, D.-S. Leem, J. S. Kwak, O. H. Nam, Y. Park, and T.-Y. Seong, “Low-resistance and highly-reflective Zn-Ni solid solution/Ag ohmic contacts for flip-chip light-emitting diodes,” Appl. Phys. Lett.83(24), 4990–4992 (2003).
[CrossRef]

Litwin, A.

S. K. Lee, C. M. Zettering, M. Ostling, I. Aberg, M. H. Magnusson, K. Deppert, L. E. Wernersson, L. Samuelson, and A. Litwin, “Reduction of the Schottky barrier height on silicon carbide using Au nano-particles,” Solid-State Electron.46(9), 1433–1440 (2002).
[CrossRef]

Liu, H.

D. L. Hibbard, S. P. Jung, C. Wang, D. Ullery, Y. S. Zhao, H. P. Lee, W. So, and H. Liu, “Low resistance high reflectance contacts to p-GaN using oxidized Ni/Au and Al or Ag,” Appl. Phys. Lett.83(2), 311–313 (2003).
[CrossRef]

Lobo, N.

N. Lobo, H. Rodriguez, A. Knauer, M. Hoppe, S. Einfeldt, P. Vogt, M. Weyers, and M. Kneissl, “Enhancement of light extraction in ultraviolet light-emitting diodes using nanopixel contact design with Al reflector,” Appl. Phys. Lett.96(8), 081109 (2010).
[CrossRef]

Luther, B. P.

B. P. Luther, J. M. DeLucca, S. E. Mohney, and R. F. Karlicek., “Analysis of a thin AlN interfacial layer in Ti/Al and Pd/Al ohmic contacts to n-type GaN,” Appl. Phys. Lett.71(26), 3859–3861 (1997).
[CrossRef]

Magnusson, M. H.

S. K. Lee, C. M. Zettering, M. Ostling, I. Aberg, M. H. Magnusson, K. Deppert, L. E. Wernersson, L. Samuelson, and A. Litwin, “Reduction of the Schottky barrier height on silicon carbide using Au nano-particles,” Solid-State Electron.46(9), 1433–1440 (2002).
[CrossRef]

Mohney, S. E.

B. P. Luther, J. M. DeLucca, S. E. Mohney, and R. F. Karlicek., “Analysis of a thin AlN interfacial layer in Ti/Al and Pd/Al ohmic contacts to n-type GaN,” Appl. Phys. Lett.71(26), 3859–3861 (1997).
[CrossRef]

Mori, F.

H. Tsuzuki, F. Mori, K. Takeda, M. Iwaya, S. Kamiyama, H. Amano, I. Akasaki, H. Yoshida, M. Kuwabara, Y. Yamashita, and H. Kan, “Novel UV devices on high-quality AlGaN using grooved underlying layer,” J. Cryst. Growth311(10), 2860–2863 (2009).
[CrossRef]

Nam, O. H.

J.-O. Song, D.-S. Leem, J. S. Kwak, O. H. Nam, Y. Park, and T.-Y. Seong, “Low-resistance and highly-reflective Zn-Ni solid solution/Ag ohmic contacts for flip-chip light-emitting diodes,” Appl. Phys. Lett.83(24), 4990–4992 (2003).
[CrossRef]

Ostling, M.

S. K. Lee, C. M. Zettering, M. Ostling, I. Aberg, M. H. Magnusson, K. Deppert, L. E. Wernersson, L. Samuelson, and A. Litwin, “Reduction of the Schottky barrier height on silicon carbide using Au nano-particles,” Solid-State Electron.46(9), 1433–1440 (2002).
[CrossRef]

Park, Y.

H. Kim, K. H. Baik, J. Cho, J. W. Lee, S. Yoon, H. Kim, S. N. Lee, C. Sone, Y. Park, and T.-Y. Seong, “High-reflectance and thermally stable AgCu alloy p-type reflectors for GaN-based light-emitting diodes,” IEEE Photon. Technol. Lett.19(5), 336–338 (2007).
[CrossRef]

J.-O. Song, W.-G. Hong, J. S. Kwak, Y. Park, and T.-Y. Seong, “Low-resistance Al-based reflectors for high-power GaN-based flip-chip light-emitting diodes,” Appl. Phys. Lett.86(13), 133503 (2005).
[CrossRef]

J.-O. Song, S. Kwak, Y. Park, and T.-Y. Seong, “Improvement of the light output of InGaN-based light-emitting diodes using Cu-doped indium oxide/indium tin oxide p-type electrodes,” Appl. Phys. Lett.86(21), 213505 (2005).
[CrossRef]

J.-O. Song, D.-S. Leem, J. S. Kwak, O. H. Nam, Y. Park, and T.-Y. Seong, “Low-resistance and highly-reflective Zn-Ni solid solution/Ag ohmic contacts for flip-chip light-emitting diodes,” Appl. Phys. Lett.83(24), 4990–4992 (2003).
[CrossRef]

Rodriguez, H.

N. Lobo, H. Rodriguez, A. Knauer, M. Hoppe, S. Einfeldt, P. Vogt, M. Weyers, and M. Kneissl, “Enhancement of light extraction in ultraviolet light-emitting diodes using nanopixel contact design with Al reflector,” Appl. Phys. Lett.96(8), 081109 (2010).
[CrossRef]

Samuelson, L.

S. K. Lee, C. M. Zettering, M. Ostling, I. Aberg, M. H. Magnusson, K. Deppert, L. E. Wernersson, L. Samuelson, and A. Litwin, “Reduction of the Schottky barrier height on silicon carbide using Au nano-particles,” Solid-State Electron.46(9), 1433–1440 (2002).
[CrossRef]

Seong, T.-Y.

J.-O. Song, J.-S. Ha, and T.-Y. Seong, “Ohmic-contact technology for GaN-based light-emitting diodes: role of P-type contact,” IEEE Trans. Electron. Dev.57(1), 42–59 (2010).
[CrossRef]

H. Kim, K. H. Baik, J. Cho, J. W. Lee, S. Yoon, H. Kim, S. N. Lee, C. Sone, Y. Park, and T.-Y. Seong, “High-reflectance and thermally stable AgCu alloy p-type reflectors for GaN-based light-emitting diodes,” IEEE Photon. Technol. Lett.19(5), 336–338 (2007).
[CrossRef]

J.-O. Song, W.-G. Hong, J. S. Kwak, Y. Park, and T.-Y. Seong, “Low-resistance Al-based reflectors for high-power GaN-based flip-chip light-emitting diodes,” Appl. Phys. Lett.86(13), 133503 (2005).
[CrossRef]

J.-O. Song, S. Kwak, Y. Park, and T.-Y. Seong, “Improvement of the light output of InGaN-based light-emitting diodes using Cu-doped indium oxide/indium tin oxide p-type electrodes,” Appl. Phys. Lett.86(21), 213505 (2005).
[CrossRef]

J.-O. Song and T.-Y. Seong, “Highly transparent Ag/SnO2 ohmic contact to p-type GaN for ultraviolet light-emitting diodes,” Appl. Phys. Lett.85(26), 6374–6376 (2004).
[CrossRef]

J. I. Sohn, J.-O. Song, D.-S. Leem, S. Lee, and T.-Y. Seong, “Formation of nonalloyed low resistance Ni/Au ohmic contacts to p-type GaN using Au nano-dots,” Electrochem. Solid-State Lett.7(9), G179–G181 (2004).
[CrossRef]

J.-O. Song, D.-S. Leem, J. S. Kwak, O. H. Nam, Y. Park, and T.-Y. Seong, “Low-resistance and highly-reflective Zn-Ni solid solution/Ag ohmic contacts for flip-chip light-emitting diodes,” Appl. Phys. Lett.83(24), 4990–4992 (2003).
[CrossRef]

Shatalov, M.

W. Sun, V. Adivarahan, M. Shatalov, Y. Lee, S. Wu, J. Yang, J. Zhang, and M. A. Khan, “Continuous wave milliwatt power AlGaN light emitting diodes at 280 nm,” Jpn. J. Appl. Phys.43(No. 11A), L1419–L1421 (2004).
[CrossRef]

So, W.

D. L. Hibbard, S. P. Jung, C. Wang, D. Ullery, Y. S. Zhao, H. P. Lee, W. So, and H. Liu, “Low resistance high reflectance contacts to p-GaN using oxidized Ni/Au and Al or Ag,” Appl. Phys. Lett.83(2), 311–313 (2003).
[CrossRef]

Sohn, J. I.

J. I. Sohn, J.-O. Song, D.-S. Leem, S. Lee, and T.-Y. Seong, “Formation of nonalloyed low resistance Ni/Au ohmic contacts to p-type GaN using Au nano-dots,” Electrochem. Solid-State Lett.7(9), G179–G181 (2004).
[CrossRef]

Son, J. H.

Sone, C.

H. Kim, K. H. Baik, J. Cho, J. W. Lee, S. Yoon, H. Kim, S. N. Lee, C. Sone, Y. Park, and T.-Y. Seong, “High-reflectance and thermally stable AgCu alloy p-type reflectors for GaN-based light-emitting diodes,” IEEE Photon. Technol. Lett.19(5), 336–338 (2007).
[CrossRef]

Song, J.-O.

J.-O. Song, J.-S. Ha, and T.-Y. Seong, “Ohmic-contact technology for GaN-based light-emitting diodes: role of P-type contact,” IEEE Trans. Electron. Dev.57(1), 42–59 (2010).
[CrossRef]

J.-O. Song, W.-G. Hong, J. S. Kwak, Y. Park, and T.-Y. Seong, “Low-resistance Al-based reflectors for high-power GaN-based flip-chip light-emitting diodes,” Appl. Phys. Lett.86(13), 133503 (2005).
[CrossRef]

J.-O. Song, S. Kwak, Y. Park, and T.-Y. Seong, “Improvement of the light output of InGaN-based light-emitting diodes using Cu-doped indium oxide/indium tin oxide p-type electrodes,” Appl. Phys. Lett.86(21), 213505 (2005).
[CrossRef]

J.-O. Song and T.-Y. Seong, “Highly transparent Ag/SnO2 ohmic contact to p-type GaN for ultraviolet light-emitting diodes,” Appl. Phys. Lett.85(26), 6374–6376 (2004).
[CrossRef]

J. I. Sohn, J.-O. Song, D.-S. Leem, S. Lee, and T.-Y. Seong, “Formation of nonalloyed low resistance Ni/Au ohmic contacts to p-type GaN using Au nano-dots,” Electrochem. Solid-State Lett.7(9), G179–G181 (2004).
[CrossRef]

J.-O. Song, D.-S. Leem, J. S. Kwak, O. H. Nam, Y. Park, and T.-Y. Seong, “Low-resistance and highly-reflective Zn-Ni solid solution/Ag ohmic contacts for flip-chip light-emitting diodes,” Appl. Phys. Lett.83(24), 4990–4992 (2003).
[CrossRef]

Sun, W.

W. Sun, V. Adivarahan, M. Shatalov, Y. Lee, S. Wu, J. Yang, J. Zhang, and M. A. Khan, “Continuous wave milliwatt power AlGaN light emitting diodes at 280 nm,” Jpn. J. Appl. Phys.43(No. 11A), L1419–L1421 (2004).
[CrossRef]

Takeda, K.

K. Takehara, K. Takeda, S. Ito, H. Aoshima, M. Iwaya, T. Takeuchi, S. Kamiyama, I. Akasaki, and H. Amano, “Indium-tin oxide/Al reflective electrodes for ultraviolet light-emitting diodes,” Jpn. J. Appl. Phys.51, 042101 (2012).
[CrossRef]

H. Tsuzuki, F. Mori, K. Takeda, M. Iwaya, S. Kamiyama, H. Amano, I. Akasaki, H. Yoshida, M. Kuwabara, Y. Yamashita, and H. Kan, “Novel UV devices on high-quality AlGaN using grooved underlying layer,” J. Cryst. Growth311(10), 2860–2863 (2009).
[CrossRef]

Takehara, K.

K. Takehara, K. Takeda, S. Ito, H. Aoshima, M. Iwaya, T. Takeuchi, S. Kamiyama, I. Akasaki, and H. Amano, “Indium-tin oxide/Al reflective electrodes for ultraviolet light-emitting diodes,” Jpn. J. Appl. Phys.51, 042101 (2012).
[CrossRef]

Takeuchi, T.

K. Takehara, K. Takeda, S. Ito, H. Aoshima, M. Iwaya, T. Takeuchi, S. Kamiyama, I. Akasaki, and H. Amano, “Indium-tin oxide/Al reflective electrodes for ultraviolet light-emitting diodes,” Jpn. J. Appl. Phys.51, 042101 (2012).
[CrossRef]

Teepe, M.

M. Kneissl, Z. Yang, M. Teepe, C. Knollenberg, N. M. Johnson, A. Usikov, and V. Dmitriev, “Ultraviolet InAlGaN light emitting diodes grown on hydride vapor phase epitaxy AlGaN/sapphire templates,” Jpn. J. Appl. Phys.45(5A), 3905–3908 (2006).
[CrossRef]

Tsuzuki, H.

H. Tsuzuki, F. Mori, K. Takeda, M. Iwaya, S. Kamiyama, H. Amano, I. Akasaki, H. Yoshida, M. Kuwabara, Y. Yamashita, and H. Kan, “Novel UV devices on high-quality AlGaN using grooved underlying layer,” J. Cryst. Growth311(10), 2860–2863 (2009).
[CrossRef]

Tung, R. T.

R. T. Tung, “Electron transport at metal-semiconductor interfaces: General theory,” Phys. Rev. B Condens. Matter45(23), 13509–13523 (1992).
[CrossRef] [PubMed]

Ullery, D.

D. L. Hibbard, S. P. Jung, C. Wang, D. Ullery, Y. S. Zhao, H. P. Lee, W. So, and H. Liu, “Low resistance high reflectance contacts to p-GaN using oxidized Ni/Au and Al or Ag,” Appl. Phys. Lett.83(2), 311–313 (2003).
[CrossRef]

Usikov, A.

M. Kneissl, Z. Yang, M. Teepe, C. Knollenberg, N. M. Johnson, A. Usikov, and V. Dmitriev, “Ultraviolet InAlGaN light emitting diodes grown on hydride vapor phase epitaxy AlGaN/sapphire templates,” Jpn. J. Appl. Phys.45(5A), 3905–3908 (2006).
[CrossRef]

Vogt, P.

N. Lobo, H. Rodriguez, A. Knauer, M. Hoppe, S. Einfeldt, P. Vogt, M. Weyers, and M. Kneissl, “Enhancement of light extraction in ultraviolet light-emitting diodes using nanopixel contact design with Al reflector,” Appl. Phys. Lett.96(8), 081109 (2010).
[CrossRef]

Wang, C.

D. L. Hibbard, S. P. Jung, C. Wang, D. Ullery, Y. S. Zhao, H. P. Lee, W. So, and H. Liu, “Low resistance high reflectance contacts to p-GaN using oxidized Ni/Au and Al or Ag,” Appl. Phys. Lett.83(2), 311–313 (2003).
[CrossRef]

Wernersson, L. E.

S. K. Lee, C. M. Zettering, M. Ostling, I. Aberg, M. H. Magnusson, K. Deppert, L. E. Wernersson, L. Samuelson, and A. Litwin, “Reduction of the Schottky barrier height on silicon carbide using Au nano-particles,” Solid-State Electron.46(9), 1433–1440 (2002).
[CrossRef]

Weyers, M.

N. Lobo, H. Rodriguez, A. Knauer, M. Hoppe, S. Einfeldt, P. Vogt, M. Weyers, and M. Kneissl, “Enhancement of light extraction in ultraviolet light-emitting diodes using nanopixel contact design with Al reflector,” Appl. Phys. Lett.96(8), 081109 (2010).
[CrossRef]

Wu, S.

W. Sun, V. Adivarahan, M. Shatalov, Y. Lee, S. Wu, J. Yang, J. Zhang, and M. A. Khan, “Continuous wave milliwatt power AlGaN light emitting diodes at 280 nm,” Jpn. J. Appl. Phys.43(No. 11A), L1419–L1421 (2004).
[CrossRef]

Yamashita, Y.

H. Tsuzuki, F. Mori, K. Takeda, M. Iwaya, S. Kamiyama, H. Amano, I. Akasaki, H. Yoshida, M. Kuwabara, Y. Yamashita, and H. Kan, “Novel UV devices on high-quality AlGaN using grooved underlying layer,” J. Cryst. Growth311(10), 2860–2863 (2009).
[CrossRef]

Yang, J.

W. Sun, V. Adivarahan, M. Shatalov, Y. Lee, S. Wu, J. Yang, J. Zhang, and M. A. Khan, “Continuous wave milliwatt power AlGaN light emitting diodes at 280 nm,” Jpn. J. Appl. Phys.43(No. 11A), L1419–L1421 (2004).
[CrossRef]

Yang, Z.

M. Kneissl, Z. Yang, M. Teepe, C. Knollenberg, N. M. Johnson, A. Usikov, and V. Dmitriev, “Ultraviolet InAlGaN light emitting diodes grown on hydride vapor phase epitaxy AlGaN/sapphire templates,” Jpn. J. Appl. Phys.45(5A), 3905–3908 (2006).
[CrossRef]

Yoon, S.

H. Kim, K. H. Baik, J. Cho, J. W. Lee, S. Yoon, H. Kim, S. N. Lee, C. Sone, Y. Park, and T.-Y. Seong, “High-reflectance and thermally stable AgCu alloy p-type reflectors for GaN-based light-emitting diodes,” IEEE Photon. Technol. Lett.19(5), 336–338 (2007).
[CrossRef]

Yoshida, H.

H. Tsuzuki, F. Mori, K. Takeda, M. Iwaya, S. Kamiyama, H. Amano, I. Akasaki, H. Yoshida, M. Kuwabara, Y. Yamashita, and H. Kan, “Novel UV devices on high-quality AlGaN using grooved underlying layer,” J. Cryst. Growth311(10), 2860–2863 (2009).
[CrossRef]

Zettering, C. M.

S. K. Lee, C. M. Zettering, M. Ostling, I. Aberg, M. H. Magnusson, K. Deppert, L. E. Wernersson, L. Samuelson, and A. Litwin, “Reduction of the Schottky barrier height on silicon carbide using Au nano-particles,” Solid-State Electron.46(9), 1433–1440 (2002).
[CrossRef]

Zhang, J.

W. Sun, V. Adivarahan, M. Shatalov, Y. Lee, S. Wu, J. Yang, J. Zhang, and M. A. Khan, “Continuous wave milliwatt power AlGaN light emitting diodes at 280 nm,” Jpn. J. Appl. Phys.43(No. 11A), L1419–L1421 (2004).
[CrossRef]

Zhao, Y. S.

D. L. Hibbard, S. P. Jung, C. Wang, D. Ullery, Y. S. Zhao, H. P. Lee, W. So, and H. Liu, “Low resistance high reflectance contacts to p-GaN using oxidized Ni/Au and Al or Ag,” Appl. Phys. Lett.83(2), 311–313 (2003).
[CrossRef]

Appl. Phys. Lett. (8)

J.-O. Song, D.-S. Leem, J. S. Kwak, O. H. Nam, Y. Park, and T.-Y. Seong, “Low-resistance and highly-reflective Zn-Ni solid solution/Ag ohmic contacts for flip-chip light-emitting diodes,” Appl. Phys. Lett.83(24), 4990–4992 (2003).
[CrossRef]

J.-O. Song, W.-G. Hong, J. S. Kwak, Y. Park, and T.-Y. Seong, “Low-resistance Al-based reflectors for high-power GaN-based flip-chip light-emitting diodes,” Appl. Phys. Lett.86(13), 133503 (2005).
[CrossRef]

N. Lobo, H. Rodriguez, A. Knauer, M. Hoppe, S. Einfeldt, P. Vogt, M. Weyers, and M. Kneissl, “Enhancement of light extraction in ultraviolet light-emitting diodes using nanopixel contact design with Al reflector,” Appl. Phys. Lett.96(8), 081109 (2010).
[CrossRef]

B. P. Luther, J. M. DeLucca, S. E. Mohney, and R. F. Karlicek., “Analysis of a thin AlN interfacial layer in Ti/Al and Pd/Al ohmic contacts to n-type GaN,” Appl. Phys. Lett.71(26), 3859–3861 (1997).
[CrossRef]

D. L. Hibbard, S. P. Jung, C. Wang, D. Ullery, Y. S. Zhao, H. P. Lee, W. So, and H. Liu, “Low resistance high reflectance contacts to p-GaN using oxidized Ni/Au and Al or Ag,” Appl. Phys. Lett.83(2), 311–313 (2003).
[CrossRef]

J.-O. Song and T.-Y. Seong, “Highly transparent Ag/SnO2 ohmic contact to p-type GaN for ultraviolet light-emitting diodes,” Appl. Phys. Lett.85(26), 6374–6376 (2004).
[CrossRef]

J.-O. Song, S. Kwak, Y. Park, and T.-Y. Seong, “Improvement of the light output of InGaN-based light-emitting diodes using Cu-doped indium oxide/indium tin oxide p-type electrodes,” Appl. Phys. Lett.86(21), 213505 (2005).
[CrossRef]

H. W. Jang and J.-L. Lee, “Mechanism for ohmic contact formation of Ni/Ag contacts on p-type GaN,” Appl. Phys. Lett.85(24), 5920–5922 (2004).
[CrossRef]

Electrochem. Solid-State Lett. (1)

J. I. Sohn, J.-O. Song, D.-S. Leem, S. Lee, and T.-Y. Seong, “Formation of nonalloyed low resistance Ni/Au ohmic contacts to p-type GaN using Au nano-dots,” Electrochem. Solid-State Lett.7(9), G179–G181 (2004).
[CrossRef]

IEEE J. Quantum Electron. (1)

W. H. Lee, D. J. Chae, D. Y. Kim, and T. G. Kim, “Improved electrical and optical properties of vertical GaN LEDs using fluorine-doped ITO/Al ohmic reflectors,” IEEE J. Quantum Electron.47(10), 1277–1282 (2011).
[CrossRef]

IEEE Photon. Technol. Lett. (1)

H. Kim, K. H. Baik, J. Cho, J. W. Lee, S. Yoon, H. Kim, S. N. Lee, C. Sone, Y. Park, and T.-Y. Seong, “High-reflectance and thermally stable AgCu alloy p-type reflectors for GaN-based light-emitting diodes,” IEEE Photon. Technol. Lett.19(5), 336–338 (2007).
[CrossRef]

IEEE Trans. Electron. Dev. (1)

J.-O. Song, J.-S. Ha, and T.-Y. Seong, “Ohmic-contact technology for GaN-based light-emitting diodes: role of P-type contact,” IEEE Trans. Electron. Dev.57(1), 42–59 (2010).
[CrossRef]

J. Cryst. Growth (1)

H. Tsuzuki, F. Mori, K. Takeda, M. Iwaya, S. Kamiyama, H. Amano, I. Akasaki, H. Yoshida, M. Kuwabara, Y. Yamashita, and H. Kan, “Novel UV devices on high-quality AlGaN using grooved underlying layer,” J. Cryst. Growth311(10), 2860–2863 (2009).
[CrossRef]

J. Electrochem. Soc. (1)

I.-C. Chen, Y.-D. Chen, C.-C. Hsieh, C.-H. Kuo, and L.-C. Chang, “Highly reflective Ag/La bilayer ohmic contacts to p-type GaN,” J. Electrochem. Soc.158(3), H285–H288 (2011).
[CrossRef]

Jpn. J. Appl. Phys. (3)

W. Sun, V. Adivarahan, M. Shatalov, Y. Lee, S. Wu, J. Yang, J. Zhang, and M. A. Khan, “Continuous wave milliwatt power AlGaN light emitting diodes at 280 nm,” Jpn. J. Appl. Phys.43(No. 11A), L1419–L1421 (2004).
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Figures (5)

Fig. 1
Fig. 1

Schematic diagram of LED structures fabricated with (a) CIO/ITO/Al and (b) Ag nano-dot/CIO/ITO/Al reflectors.

Fig. 2
Fig. 2

The reflectance of Al contacts with different ITO-based multilayers. All of the layers were e-beam evaporated except for s-ITO that was sputter-deposited. The inset shows an AFM image of Ag nano-dots formed on p-GaN.

Fig. 3
Fig. 3

The typical I-V characteristics of near-UV (365 nm) InGaN/AlGaN MQW LEDs fabricated with Al contacts with different ITO-based multilayers. The inset shows the current-voltage characteristics of different ITO-based contacts.

Fig. 4
Fig. 4

The light output-current (L-I) characteristics of near-UV LEDs fabricated with Al reflectors with different ITO-based multilayers.

Fig. 5
Fig. 5

The XPS Ga 2p core level spectra obtained from (a) CIO/s-ITO/Al and (b) n-Ag/CIO/s-ITO/Al contacts, both of which were annealed at 500°C before the deposition of an Al layer.

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