Abstract

High-power and reliable GaN-based vertical light-emitting diodes (V-LEDs) on 4-inch silicon substrate were fabricated and characterized in this article. The metallization scheme reliability was improved by depositing the Pt/Ti films that surround the compressed Ag/TiW films to protect it from environmental humidity. We demonstrated that although current crowding in V-LEDs was not as severe as that in lateral light-emitting diodes (L-LEDs), high current density around the opaque metal n-electrode in V-LEDs remained a problem. A SiO2 current blocking layer (CBL) was incorporated in V-LEDs to modify the current distribution. Roughening the emitting surface of V-LEDs with KOH and H3PO4 etchant was compared and the influence of surface roughening on the emission property of V-LEDs was studied. The high-power V-LEDs showed low forward voltage with small series resistance and high light output power (LOP) without saturation up to 1300 mA. Under 350 mA injection current, V-LEDs achieved an excellent light output power (LOP) of 501 mW with the peak emission wavelength at 453 nm. The prominent output performance of V-LEDs demonstrated in this work confirmed that integrating the optimized metallization scheme, SiO2 CBL and surface texturing by KOH wet etching is an effective approach to higher performance V-LEDs.

© 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

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References

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    [Crossref]
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    [Crossref]

2019 (5)

S. Zhou, H. Xu, H. Hu, C. Gui, and S. Liu, “High quality GaN buffer layer by isoelectronic doping and its application to 365 nm InGaN/AlGaN ultraviolet light-emitting diodes,” Appl. Surf. Sci. 471, 231–238 (2019).
[Crossref]

B. Tang, J. Miao, Y. Liu, H. Wan, N. Li, S. Zhou, and C. Gui, “Enhanced Light Extraction of Flip-Chip Mini-LEDs with Prism-Structured Sidewall,” Nanomaterials (Basel) 9(3), 319 (2019).
[Crossref] [PubMed]

S. H. Oh, T. H. Lee, K.-R. Son, and T. G. Kim, “Fabrication of HfO2/TiO2–based conductive distributed Bragg reflectors: Its application to GaN-based near-ultraviolet micro-light-emitting diodes,” J. Alloys Compd. 773, 490–495 (2019).
[Crossref]

S. Zhou, X. Liu, H. Yan, Z. Chen, Y. Liu, and S. Liu, “Highly efficient GaN-based high-power flip-chip light-emitting diodes,” Opt. Express 27(12), A669–A692 (2019).
[Crossref] [PubMed]

Z. Zhang, F. Gao, Y. Zhang, and G. Li, “Impact of Silver Surface Morphology on the Wall Plug Efficiency of Blue Vertical Light-Emitting Diodes,” IEEE Trans. Electron Dev. 66(6), 2643–2650 (2019).
[Crossref]

2018 (1)

2017 (1)

M. A. Khan, H. Chen, J. Qu, P. W. Trimby, S. Moody, Y. Yao, S. P. Ringer, and R. Zheng, “Insights into the Silver Reflection Layer of a Vertical LED for Light Emission Optimization,” ACS Appl. Mater. Interfaces 9(28), 24259–24272 (2017).
[Crossref] [PubMed]

2016 (3)

L. Wang, E. Guo, Z. Liu, X. Yi, and G. Wang, “High-Performance Nitride Vertical Light-Emitting Diodes Based on Cu Electroplating Technical Route,” IEEE Trans. Electron Dev. 63(3), 892–902 (2016).
[Crossref]

N. Hasanov, B. Zhu, V. K. Sharma, S. Lu, Y. Zhang, W. Liu, S. T. Tan, X. W. Sun, and H. V. Demir, “Improved performance of InGaN/GaN flip-chip light-emitting diodes through the use of robust Ni/Ag/TiW mirror contacts,” J. Vac. Sci. Technol. B 34(1), 011209 (2016).
[Crossref]

S. Singh, A. D. S. Nandini, S. Pal, and C. Dhanavantri, “Enhancement of light extraction efficiency of vertical LED with patterned graphene as current spreading layer,” Superlattices Microstruct. 89, 89–96 (2016).
[Crossref]

2015 (4)

T. M. Chang, H. K. Fang, C. Liao, W. Y. Hsu, and Y. S. Wu, “Laser Lift-Off Mechanisms of GaN Epi-Layer Grown on Pattern Sapphire Substrate,” ECS J. Solid State Sci. Technol. 4(2), R20–R22 (2015).
[Crossref]

J. Han, D. Lee, B. Jin, H. Jeong, J.-O. Song, and T.-Y. Seong, “Optimizing n-type contact design, and chip size for high-performance indium gallium nitride/gallium nitride-based thin-film vertical light-emitting diode,” Mater. Sci. Semicond. Process. 31, 153–159 (2015).
[Crossref]

S. Zhou, S. Yuan, Y. Liu, L. J. Guo, S. Liu, and H. Ding, “Highly efficient and reliable high power LEDs with patterned sapphire substrate and strip-shaped distributed current blocking layer,” Appl. Surf. Sci. 355, 1013–1019 (2015).
[Crossref]

P. Pust, P. J. Schmidt, and W. Schnick, “A revolution in lighting,” Nat. Mater. 14(5), 454–458 (2015).
[Crossref] [PubMed]

2014 (2)

Y. Muramoto, M. Kimura, and S. Nouda, “Development and future of ultraviolet light-emitting diodes: UV-LED will replace the UV lamp,” Semicond. Sci. Technol. 29(8), 084004 (2014).
[Crossref]

D.-H. Kim, W. C. Lim, J.-S. Park, and T.-Y. Seong, “Highly thermally stable Pd/Zn/Ag ohmic contact to Ga-face p-type GaN,” J. Alloys Compd. 588, 327–331 (2014).
[Crossref]

2012 (3)

J.-Y. Faou, G. Parry, S. Grachev, and E. Barthel, “How Does Adhesion Induce the Formation of Telephone Cord Buckles?” Phys. Rev. Lett. 108(11), 116102 (2012).
[Crossref] [PubMed]

J. H. Son, B. J. Kim, C. J. Ryu, Y. H. Song, H. K. Lee, J. W. Choi, and J. L. Lee, “Enhancement of wall-plug efficiency in vertical InGaN/GaN LEDs by improved current spreading,” Opt. Express 20, A287–A292 (2012).
[Crossref] [PubMed]

V. K. Malyutenko, S. S. Bolgov, and A. N. Tykhonov, “Research on Electrical Efficiency Degradation Influenced by Current Crowding in Vertical Blue InGaN-on-SiC Light-Emitting Diodes,” IEEE Photonics Technol. Lett. 24(13), 1124–1126 (2012).
[Crossref]

2011 (1)

A. I. Zhmakin, “Enhancement of light extraction from light emitting diodes,” Phys. Rep. 498, 189–241 (2011).
[Crossref]

2010 (1)

C. Chu, C. Cheng, W. Liu, J. Chu, F. Fan, H. Cheng, T. Doan, and C. A. Tran, “High Brightness GaN Vertical Light-Emitting Diodes on Metal Alloy for General Lighting Application,” Proc. IEEE 98(7), 1197–1207 (2010).
[Crossref]

2009 (2)

M. H. Crawford, “LEDs for Solid-State Lighting: Performance Challenges and Recent Advances,” IEEE J. Sel. Top. Quantum Electron. 15(4), 1028–1040 (2009).
[Crossref]

H. Jia, L. Guo, W. Wang, and H. Chen, “Recent Progress in GaN-Based Light-Emitting Diodes,” Adv. Mater. 21(45), 4641–4646 (2009).
[Crossref]

2007 (2)

P. Waters and A. A. Volinsky, “Stress and Moisture Effects on Thin Film Buckling Delamination,” Exp. Mech. 47(1), 163–170 (2007).
[Crossref]

K. A. Bulashevich, I. Y. Evstratov, V. F. Mymrin, and S. Y. Karpov, “Current spreading and thermal effects in blue LED dice,” Phys. Status Solidi., C Curr. Top. Solid State Phys. 4(1), 45–48 (2007).
[Crossref]

2006 (1)

D.-S. Leem, T.-W. Kim, T. Lee, J.-S. Jang, Y.-W. Ok, and T.-Y. Seong, “Formation mechanism of cerium oxide-doped indium oxide/Ag Ohmic contacts on p-type GaN,” Appl. Phys. Lett. 89(26), 262115 (2006).
[Crossref]

2004 (2)

T. Fujii, Y. Gao, R. Sharma, E. L. Hu, S. P. DenBaars, and S. Nakamura, “Increase in the extraction efficiency of GaN-based light-emitting diodes via surface roughening,” Appl. Phys. Lett. 84(6), 855–857 (2004).
[Crossref]

D.-S. Wuu, S.-C. Hsu, S.-H. Huang, C.-C. Wu, C.-E. Lee, and R.-H. Horng, “GaN/Mirror/Si Light-Emitting Diodes for Vertical Current Injection by Laser Lift-Off and Wafer Bonding Techniques,” Jpn. J. Appl. Phys. 43(8A8R), 5239–5242 (2004).
[Crossref]

1995 (1)

V. G. Glebovsky, V. Y. Yaschak, V. V. Baranov, and E. L. Sackovich, “Properties of titanium-tungsten thin films obtained by magnetron sputtering of composite cast targets,” Thin Solid Films 257(1), 1–6 (1995).
[Crossref]

1993 (1)

C. C. Lee, C. Y. Wang, and G. Matijasevic, ““Au-In bonding below the eutectic temperature,” IEEE Trans. Compon., Hybrids, Manuf. Technol. 16(3), 311–316 (1993).

1991 (1)

M. Itoh, M. Hori, and S. Nadahara, “The Origin of Stress in Sputter-Deposited Tungsten Films for X-Ray Masks,” J. Vac. Sci. Technol. B 9(1), 149–153 (1991).
[Crossref]

1984 (1)

M. A. Taubenblatt, D. Thomson, and C. R. Helms, “Interface effects in titanium and hafnium Schottky barriers on silicon,” Appl. Phys. Lett. 44(9), 895–897 (1984).
[Crossref]

1921 (1)

A. A. Griffith and G. I. Taylor, “VI. The phenomena of rupture and flow in solids,” Philos. Trans. R. Soc. Lond. A 221(582-593), 163–198 (1921).
[Crossref]

Baranov, V. V.

V. G. Glebovsky, V. Y. Yaschak, V. V. Baranov, and E. L. Sackovich, “Properties of titanium-tungsten thin films obtained by magnetron sputtering of composite cast targets,” Thin Solid Films 257(1), 1–6 (1995).
[Crossref]

Barthel, E.

J.-Y. Faou, G. Parry, S. Grachev, and E. Barthel, “How Does Adhesion Induce the Formation of Telephone Cord Buckles?” Phys. Rev. Lett. 108(11), 116102 (2012).
[Crossref] [PubMed]

Bolgov, S. S.

V. K. Malyutenko, S. S. Bolgov, and A. N. Tykhonov, “Research on Electrical Efficiency Degradation Influenced by Current Crowding in Vertical Blue InGaN-on-SiC Light-Emitting Diodes,” IEEE Photonics Technol. Lett. 24(13), 1124–1126 (2012).
[Crossref]

Bulashevich, K. A.

K. A. Bulashevich, I. Y. Evstratov, V. F. Mymrin, and S. Y. Karpov, “Current spreading and thermal effects in blue LED dice,” Phys. Status Solidi., C Curr. Top. Solid State Phys. 4(1), 45–48 (2007).
[Crossref]

Chang, T. M.

T. M. Chang, H. K. Fang, C. Liao, W. Y. Hsu, and Y. S. Wu, “Laser Lift-Off Mechanisms of GaN Epi-Layer Grown on Pattern Sapphire Substrate,” ECS J. Solid State Sci. Technol. 4(2), R20–R22 (2015).
[Crossref]

Chen, H.

M. A. Khan, H. Chen, J. Qu, P. W. Trimby, S. Moody, Y. Yao, S. P. Ringer, and R. Zheng, “Insights into the Silver Reflection Layer of a Vertical LED for Light Emission Optimization,” ACS Appl. Mater. Interfaces 9(28), 24259–24272 (2017).
[Crossref] [PubMed]

H. Jia, L. Guo, W. Wang, and H. Chen, “Recent Progress in GaN-Based Light-Emitting Diodes,” Adv. Mater. 21(45), 4641–4646 (2009).
[Crossref]

Chen, Z.

Cheng, C.

C. Chu, C. Cheng, W. Liu, J. Chu, F. Fan, H. Cheng, T. Doan, and C. A. Tran, “High Brightness GaN Vertical Light-Emitting Diodes on Metal Alloy for General Lighting Application,” Proc. IEEE 98(7), 1197–1207 (2010).
[Crossref]

Cheng, H.

C. Chu, C. Cheng, W. Liu, J. Chu, F. Fan, H. Cheng, T. Doan, and C. A. Tran, “High Brightness GaN Vertical Light-Emitting Diodes on Metal Alloy for General Lighting Application,” Proc. IEEE 98(7), 1197–1207 (2010).
[Crossref]

Choi, J. W.

Chu, C.

C. Chu, C. Cheng, W. Liu, J. Chu, F. Fan, H. Cheng, T. Doan, and C. A. Tran, “High Brightness GaN Vertical Light-Emitting Diodes on Metal Alloy for General Lighting Application,” Proc. IEEE 98(7), 1197–1207 (2010).
[Crossref]

Chu, J.

C. Chu, C. Cheng, W. Liu, J. Chu, F. Fan, H. Cheng, T. Doan, and C. A. Tran, “High Brightness GaN Vertical Light-Emitting Diodes on Metal Alloy for General Lighting Application,” Proc. IEEE 98(7), 1197–1207 (2010).
[Crossref]

Crawford, M. H.

M. H. Crawford, “LEDs for Solid-State Lighting: Performance Challenges and Recent Advances,” IEEE J. Sel. Top. Quantum Electron. 15(4), 1028–1040 (2009).
[Crossref]

Demir, H. V.

N. Hasanov, B. Zhu, V. K. Sharma, S. Lu, Y. Zhang, W. Liu, S. T. Tan, X. W. Sun, and H. V. Demir, “Improved performance of InGaN/GaN flip-chip light-emitting diodes through the use of robust Ni/Ag/TiW mirror contacts,” J. Vac. Sci. Technol. B 34(1), 011209 (2016).
[Crossref]

DenBaars, S. P.

T. Fujii, Y. Gao, R. Sharma, E. L. Hu, S. P. DenBaars, and S. Nakamura, “Increase in the extraction efficiency of GaN-based light-emitting diodes via surface roughening,” Appl. Phys. Lett. 84(6), 855–857 (2004).
[Crossref]

Dhanavantri, C.

S. Singh, A. D. S. Nandini, S. Pal, and C. Dhanavantri, “Enhancement of light extraction efficiency of vertical LED with patterned graphene as current spreading layer,” Superlattices Microstruct. 89, 89–96 (2016).
[Crossref]

Ding, H.

S. Zhou, S. Yuan, Y. Liu, L. J. Guo, S. Liu, and H. Ding, “Highly efficient and reliable high power LEDs with patterned sapphire substrate and strip-shaped distributed current blocking layer,” Appl. Surf. Sci. 355, 1013–1019 (2015).
[Crossref]

Doan, T.

C. Chu, C. Cheng, W. Liu, J. Chu, F. Fan, H. Cheng, T. Doan, and C. A. Tran, “High Brightness GaN Vertical Light-Emitting Diodes on Metal Alloy for General Lighting Application,” Proc. IEEE 98(7), 1197–1207 (2010).
[Crossref]

Evstratov, I. Y.

K. A. Bulashevich, I. Y. Evstratov, V. F. Mymrin, and S. Y. Karpov, “Current spreading and thermal effects in blue LED dice,” Phys. Status Solidi., C Curr. Top. Solid State Phys. 4(1), 45–48 (2007).
[Crossref]

Fan, F.

C. Chu, C. Cheng, W. Liu, J. Chu, F. Fan, H. Cheng, T. Doan, and C. A. Tran, “High Brightness GaN Vertical Light-Emitting Diodes on Metal Alloy for General Lighting Application,” Proc. IEEE 98(7), 1197–1207 (2010).
[Crossref]

Fang, H. K.

T. M. Chang, H. K. Fang, C. Liao, W. Y. Hsu, and Y. S. Wu, “Laser Lift-Off Mechanisms of GaN Epi-Layer Grown on Pattern Sapphire Substrate,” ECS J. Solid State Sci. Technol. 4(2), R20–R22 (2015).
[Crossref]

Faou, J.-Y.

J.-Y. Faou, G. Parry, S. Grachev, and E. Barthel, “How Does Adhesion Induce the Formation of Telephone Cord Buckles?” Phys. Rev. Lett. 108(11), 116102 (2012).
[Crossref] [PubMed]

Fujii, T.

T. Fujii, Y. Gao, R. Sharma, E. L. Hu, S. P. DenBaars, and S. Nakamura, “Increase in the extraction efficiency of GaN-based light-emitting diodes via surface roughening,” Appl. Phys. Lett. 84(6), 855–857 (2004).
[Crossref]

Gao, F.

Z. Zhang, F. Gao, Y. Zhang, and G. Li, “Impact of Silver Surface Morphology on the Wall Plug Efficiency of Blue Vertical Light-Emitting Diodes,” IEEE Trans. Electron Dev. 66(6), 2643–2650 (2019).
[Crossref]

Gao, Y.

T. Fujii, Y. Gao, R. Sharma, E. L. Hu, S. P. DenBaars, and S. Nakamura, “Increase in the extraction efficiency of GaN-based light-emitting diodes via surface roughening,” Appl. Phys. Lett. 84(6), 855–857 (2004).
[Crossref]

Glebovsky, V. G.

V. G. Glebovsky, V. Y. Yaschak, V. V. Baranov, and E. L. Sackovich, “Properties of titanium-tungsten thin films obtained by magnetron sputtering of composite cast targets,” Thin Solid Films 257(1), 1–6 (1995).
[Crossref]

Grachev, S.

J.-Y. Faou, G. Parry, S. Grachev, and E. Barthel, “How Does Adhesion Induce the Formation of Telephone Cord Buckles?” Phys. Rev. Lett. 108(11), 116102 (2012).
[Crossref] [PubMed]

Griffith, A. A.

A. A. Griffith and G. I. Taylor, “VI. The phenomena of rupture and flow in solids,” Philos. Trans. R. Soc. Lond. A 221(582-593), 163–198 (1921).
[Crossref]

Gui, C.

S. Zhou, H. Xu, H. Hu, C. Gui, and S. Liu, “High quality GaN buffer layer by isoelectronic doping and its application to 365 nm InGaN/AlGaN ultraviolet light-emitting diodes,” Appl. Surf. Sci. 471, 231–238 (2019).
[Crossref]

B. Tang, J. Miao, Y. Liu, H. Wan, N. Li, S. Zhou, and C. Gui, “Enhanced Light Extraction of Flip-Chip Mini-LEDs with Prism-Structured Sidewall,” Nanomaterials (Basel) 9(3), 319 (2019).
[Crossref] [PubMed]

Guo, E.

L. Wang, E. Guo, Z. Liu, X. Yi, and G. Wang, “High-Performance Nitride Vertical Light-Emitting Diodes Based on Cu Electroplating Technical Route,” IEEE Trans. Electron Dev. 63(3), 892–902 (2016).
[Crossref]

Guo, L.

H. Jia, L. Guo, W. Wang, and H. Chen, “Recent Progress in GaN-Based Light-Emitting Diodes,” Adv. Mater. 21(45), 4641–4646 (2009).
[Crossref]

Guo, L. J.

S. Zhou, S. Yuan, Y. Liu, L. J. Guo, S. Liu, and H. Ding, “Highly efficient and reliable high power LEDs with patterned sapphire substrate and strip-shaped distributed current blocking layer,” Appl. Surf. Sci. 355, 1013–1019 (2015).
[Crossref]

Han, J.

J. Han, D. Lee, B. Jin, H. Jeong, J.-O. Song, and T.-Y. Seong, “Optimizing n-type contact design, and chip size for high-performance indium gallium nitride/gallium nitride-based thin-film vertical light-emitting diode,” Mater. Sci. Semicond. Process. 31, 153–159 (2015).
[Crossref]

Han, J. W.

Hasanov, N.

N. Hasanov, B. Zhu, V. K. Sharma, S. Lu, Y. Zhang, W. Liu, S. T. Tan, X. W. Sun, and H. V. Demir, “Improved performance of InGaN/GaN flip-chip light-emitting diodes through the use of robust Ni/Ag/TiW mirror contacts,” J. Vac. Sci. Technol. B 34(1), 011209 (2016).
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M. A. Taubenblatt, D. Thomson, and C. R. Helms, “Interface effects in titanium and hafnium Schottky barriers on silicon,” Appl. Phys. Lett. 44(9), 895–897 (1984).
[Crossref]

Hori, M.

M. Itoh, M. Hori, and S. Nadahara, “The Origin of Stress in Sputter-Deposited Tungsten Films for X-Ray Masks,” J. Vac. Sci. Technol. B 9(1), 149–153 (1991).
[Crossref]

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D.-S. Wuu, S.-C. Hsu, S.-H. Huang, C.-C. Wu, C.-E. Lee, and R.-H. Horng, “GaN/Mirror/Si Light-Emitting Diodes for Vertical Current Injection by Laser Lift-Off and Wafer Bonding Techniques,” Jpn. J. Appl. Phys. 43(8A8R), 5239–5242 (2004).
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D.-S. Wuu, S.-C. Hsu, S.-H. Huang, C.-C. Wu, C.-E. Lee, and R.-H. Horng, “GaN/Mirror/Si Light-Emitting Diodes for Vertical Current Injection by Laser Lift-Off and Wafer Bonding Techniques,” Jpn. J. Appl. Phys. 43(8A8R), 5239–5242 (2004).
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T. M. Chang, H. K. Fang, C. Liao, W. Y. Hsu, and Y. S. Wu, “Laser Lift-Off Mechanisms of GaN Epi-Layer Grown on Pattern Sapphire Substrate,” ECS J. Solid State Sci. Technol. 4(2), R20–R22 (2015).
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T. Fujii, Y. Gao, R. Sharma, E. L. Hu, S. P. DenBaars, and S. Nakamura, “Increase in the extraction efficiency of GaN-based light-emitting diodes via surface roughening,” Appl. Phys. Lett. 84(6), 855–857 (2004).
[Crossref]

Hu, H.

S. Zhou, H. Xu, H. Hu, C. Gui, and S. Liu, “High quality GaN buffer layer by isoelectronic doping and its application to 365 nm InGaN/AlGaN ultraviolet light-emitting diodes,” Appl. Surf. Sci. 471, 231–238 (2019).
[Crossref]

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D.-S. Wuu, S.-C. Hsu, S.-H. Huang, C.-C. Wu, C.-E. Lee, and R.-H. Horng, “GaN/Mirror/Si Light-Emitting Diodes for Vertical Current Injection by Laser Lift-Off and Wafer Bonding Techniques,” Jpn. J. Appl. Phys. 43(8A8R), 5239–5242 (2004).
[Crossref]

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M. Itoh, M. Hori, and S. Nadahara, “The Origin of Stress in Sputter-Deposited Tungsten Films for X-Ray Masks,” J. Vac. Sci. Technol. B 9(1), 149–153 (1991).
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D.-S. Leem, T.-W. Kim, T. Lee, J.-S. Jang, Y.-W. Ok, and T.-Y. Seong, “Formation mechanism of cerium oxide-doped indium oxide/Ag Ohmic contacts on p-type GaN,” Appl. Phys. Lett. 89(26), 262115 (2006).
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J. Han, D. Lee, B. Jin, H. Jeong, J.-O. Song, and T.-Y. Seong, “Optimizing n-type contact design, and chip size for high-performance indium gallium nitride/gallium nitride-based thin-film vertical light-emitting diode,” Mater. Sci. Semicond. Process. 31, 153–159 (2015).
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Jia, H.

H. Jia, L. Guo, W. Wang, and H. Chen, “Recent Progress in GaN-Based Light-Emitting Diodes,” Adv. Mater. 21(45), 4641–4646 (2009).
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J. Han, D. Lee, B. Jin, H. Jeong, J.-O. Song, and T.-Y. Seong, “Optimizing n-type contact design, and chip size for high-performance indium gallium nitride/gallium nitride-based thin-film vertical light-emitting diode,” Mater. Sci. Semicond. Process. 31, 153–159 (2015).
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Kang, D. S.

Karpov, S. Y.

K. A. Bulashevich, I. Y. Evstratov, V. F. Mymrin, and S. Y. Karpov, “Current spreading and thermal effects in blue LED dice,” Phys. Status Solidi., C Curr. Top. Solid State Phys. 4(1), 45–48 (2007).
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Khan, M. A.

M. A. Khan, H. Chen, J. Qu, P. W. Trimby, S. Moody, Y. Yao, S. P. Ringer, and R. Zheng, “Insights into the Silver Reflection Layer of a Vertical LED for Light Emission Optimization,” ACS Appl. Mater. Interfaces 9(28), 24259–24272 (2017).
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Kim, D.-H.

D.-H. Kim, W. C. Lim, J.-S. Park, and T.-Y. Seong, “Highly thermally stable Pd/Zn/Ag ohmic contact to Ga-face p-type GaN,” J. Alloys Compd. 588, 327–331 (2014).
[Crossref]

Kim, T. G.

S. H. Oh, T. H. Lee, K.-R. Son, and T. G. Kim, “Fabrication of HfO2/TiO2–based conductive distributed Bragg reflectors: Its application to GaN-based near-ultraviolet micro-light-emitting diodes,” J. Alloys Compd. 773, 490–495 (2019).
[Crossref]

Kim, T.-W.

D.-S. Leem, T.-W. Kim, T. Lee, J.-S. Jang, Y.-W. Ok, and T.-Y. Seong, “Formation mechanism of cerium oxide-doped indium oxide/Ag Ohmic contacts on p-type GaN,” Appl. Phys. Lett. 89(26), 262115 (2006).
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Kimura, M.

Y. Muramoto, M. Kimura, and S. Nouda, “Development and future of ultraviolet light-emitting diodes: UV-LED will replace the UV lamp,” Semicond. Sci. Technol. 29(8), 084004 (2014).
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C. C. Lee, C. Y. Wang, and G. Matijasevic, ““Au-In bonding below the eutectic temperature,” IEEE Trans. Compon., Hybrids, Manuf. Technol. 16(3), 311–316 (1993).

Lee, C.-E.

D.-S. Wuu, S.-C. Hsu, S.-H. Huang, C.-C. Wu, C.-E. Lee, and R.-H. Horng, “GaN/Mirror/Si Light-Emitting Diodes for Vertical Current Injection by Laser Lift-Off and Wafer Bonding Techniques,” Jpn. J. Appl. Phys. 43(8A8R), 5239–5242 (2004).
[Crossref]

Lee, D.

J. Han, D. Lee, B. Jin, H. Jeong, J.-O. Song, and T.-Y. Seong, “Optimizing n-type contact design, and chip size for high-performance indium gallium nitride/gallium nitride-based thin-film vertical light-emitting diode,” Mater. Sci. Semicond. Process. 31, 153–159 (2015).
[Crossref]

Lee, H. K.

Lee, J. L.

Lee, T.

D.-S. Leem, T.-W. Kim, T. Lee, J.-S. Jang, Y.-W. Ok, and T.-Y. Seong, “Formation mechanism of cerium oxide-doped indium oxide/Ag Ohmic contacts on p-type GaN,” Appl. Phys. Lett. 89(26), 262115 (2006).
[Crossref]

Lee, T. H.

S. H. Oh, T. H. Lee, K.-R. Son, and T. G. Kim, “Fabrication of HfO2/TiO2–based conductive distributed Bragg reflectors: Its application to GaN-based near-ultraviolet micro-light-emitting diodes,” J. Alloys Compd. 773, 490–495 (2019).
[Crossref]

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D.-S. Leem, T.-W. Kim, T. Lee, J.-S. Jang, Y.-W. Ok, and T.-Y. Seong, “Formation mechanism of cerium oxide-doped indium oxide/Ag Ohmic contacts on p-type GaN,” Appl. Phys. Lett. 89(26), 262115 (2006).
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Li, G.

Z. Zhang, F. Gao, Y. Zhang, and G. Li, “Impact of Silver Surface Morphology on the Wall Plug Efficiency of Blue Vertical Light-Emitting Diodes,” IEEE Trans. Electron Dev. 66(6), 2643–2650 (2019).
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Li, N.

B. Tang, J. Miao, Y. Liu, H. Wan, N. Li, S. Zhou, and C. Gui, “Enhanced Light Extraction of Flip-Chip Mini-LEDs with Prism-Structured Sidewall,” Nanomaterials (Basel) 9(3), 319 (2019).
[Crossref] [PubMed]

Liao, C.

T. M. Chang, H. K. Fang, C. Liao, W. Y. Hsu, and Y. S. Wu, “Laser Lift-Off Mechanisms of GaN Epi-Layer Grown on Pattern Sapphire Substrate,” ECS J. Solid State Sci. Technol. 4(2), R20–R22 (2015).
[Crossref]

Lim, W. C.

D.-H. Kim, W. C. Lim, J.-S. Park, and T.-Y. Seong, “Highly thermally stable Pd/Zn/Ag ohmic contact to Ga-face p-type GaN,” J. Alloys Compd. 588, 327–331 (2014).
[Crossref]

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S. Zhou, X. Liu, H. Yan, Z. Chen, Y. Liu, and S. Liu, “Highly efficient GaN-based high-power flip-chip light-emitting diodes,” Opt. Express 27(12), A669–A692 (2019).
[Crossref] [PubMed]

S. Zhou, H. Xu, H. Hu, C. Gui, and S. Liu, “High quality GaN buffer layer by isoelectronic doping and its application to 365 nm InGaN/AlGaN ultraviolet light-emitting diodes,” Appl. Surf. Sci. 471, 231–238 (2019).
[Crossref]

S. Zhou, S. Yuan, Y. Liu, L. J. Guo, S. Liu, and H. Ding, “Highly efficient and reliable high power LEDs with patterned sapphire substrate and strip-shaped distributed current blocking layer,” Appl. Surf. Sci. 355, 1013–1019 (2015).
[Crossref]

Liu, W.

N. Hasanov, B. Zhu, V. K. Sharma, S. Lu, Y. Zhang, W. Liu, S. T. Tan, X. W. Sun, and H. V. Demir, “Improved performance of InGaN/GaN flip-chip light-emitting diodes through the use of robust Ni/Ag/TiW mirror contacts,” J. Vac. Sci. Technol. B 34(1), 011209 (2016).
[Crossref]

C. Chu, C. Cheng, W. Liu, J. Chu, F. Fan, H. Cheng, T. Doan, and C. A. Tran, “High Brightness GaN Vertical Light-Emitting Diodes on Metal Alloy for General Lighting Application,” Proc. IEEE 98(7), 1197–1207 (2010).
[Crossref]

Liu, X.

Liu, Y.

S. Zhou, X. Liu, H. Yan, Z. Chen, Y. Liu, and S. Liu, “Highly efficient GaN-based high-power flip-chip light-emitting diodes,” Opt. Express 27(12), A669–A692 (2019).
[Crossref] [PubMed]

B. Tang, J. Miao, Y. Liu, H. Wan, N. Li, S. Zhou, and C. Gui, “Enhanced Light Extraction of Flip-Chip Mini-LEDs with Prism-Structured Sidewall,” Nanomaterials (Basel) 9(3), 319 (2019).
[Crossref] [PubMed]

S. Zhou, S. Yuan, Y. Liu, L. J. Guo, S. Liu, and H. Ding, “Highly efficient and reliable high power LEDs with patterned sapphire substrate and strip-shaped distributed current blocking layer,” Appl. Surf. Sci. 355, 1013–1019 (2015).
[Crossref]

Liu, Z.

L. Wang, E. Guo, Z. Liu, X. Yi, and G. Wang, “High-Performance Nitride Vertical Light-Emitting Diodes Based on Cu Electroplating Technical Route,” IEEE Trans. Electron Dev. 63(3), 892–902 (2016).
[Crossref]

Lu, S.

N. Hasanov, B. Zhu, V. K. Sharma, S. Lu, Y. Zhang, W. Liu, S. T. Tan, X. W. Sun, and H. V. Demir, “Improved performance of InGaN/GaN flip-chip light-emitting diodes through the use of robust Ni/Ag/TiW mirror contacts,” J. Vac. Sci. Technol. B 34(1), 011209 (2016).
[Crossref]

Malyutenko, V. K.

V. K. Malyutenko, S. S. Bolgov, and A. N. Tykhonov, “Research on Electrical Efficiency Degradation Influenced by Current Crowding in Vertical Blue InGaN-on-SiC Light-Emitting Diodes,” IEEE Photonics Technol. Lett. 24(13), 1124–1126 (2012).
[Crossref]

Matijasevic, G.

C. C. Lee, C. Y. Wang, and G. Matijasevic, ““Au-In bonding below the eutectic temperature,” IEEE Trans. Compon., Hybrids, Manuf. Technol. 16(3), 311–316 (1993).

Miao, J.

B. Tang, J. Miao, Y. Liu, H. Wan, N. Li, S. Zhou, and C. Gui, “Enhanced Light Extraction of Flip-Chip Mini-LEDs with Prism-Structured Sidewall,” Nanomaterials (Basel) 9(3), 319 (2019).
[Crossref] [PubMed]

Moody, S.

M. A. Khan, H. Chen, J. Qu, P. W. Trimby, S. Moody, Y. Yao, S. P. Ringer, and R. Zheng, “Insights into the Silver Reflection Layer of a Vertical LED for Light Emission Optimization,” ACS Appl. Mater. Interfaces 9(28), 24259–24272 (2017).
[Crossref] [PubMed]

Moon, Y. T.

Muramoto, Y.

Y. Muramoto, M. Kimura, and S. Nouda, “Development and future of ultraviolet light-emitting diodes: UV-LED will replace the UV lamp,” Semicond. Sci. Technol. 29(8), 084004 (2014).
[Crossref]

Mymrin, V. F.

K. A. Bulashevich, I. Y. Evstratov, V. F. Mymrin, and S. Y. Karpov, “Current spreading and thermal effects in blue LED dice,” Phys. Status Solidi., C Curr. Top. Solid State Phys. 4(1), 45–48 (2007).
[Crossref]

Nadahara, S.

M. Itoh, M. Hori, and S. Nadahara, “The Origin of Stress in Sputter-Deposited Tungsten Films for X-Ray Masks,” J. Vac. Sci. Technol. B 9(1), 149–153 (1991).
[Crossref]

Nakamura, S.

T. Fujii, Y. Gao, R. Sharma, E. L. Hu, S. P. DenBaars, and S. Nakamura, “Increase in the extraction efficiency of GaN-based light-emitting diodes via surface roughening,” Appl. Phys. Lett. 84(6), 855–857 (2004).
[Crossref]

Nandini, A. D. S.

S. Singh, A. D. S. Nandini, S. Pal, and C. Dhanavantri, “Enhancement of light extraction efficiency of vertical LED with patterned graphene as current spreading layer,” Superlattices Microstruct. 89, 89–96 (2016).
[Crossref]

Nouda, S.

Y. Muramoto, M. Kimura, and S. Nouda, “Development and future of ultraviolet light-emitting diodes: UV-LED will replace the UV lamp,” Semicond. Sci. Technol. 29(8), 084004 (2014).
[Crossref]

Oh, J. T.

Oh, S. H.

S. H. Oh, T. H. Lee, K.-R. Son, and T. G. Kim, “Fabrication of HfO2/TiO2–based conductive distributed Bragg reflectors: Its application to GaN-based near-ultraviolet micro-light-emitting diodes,” J. Alloys Compd. 773, 490–495 (2019).
[Crossref]

Ok, Y.-W.

D.-S. Leem, T.-W. Kim, T. Lee, J.-S. Jang, Y.-W. Ok, and T.-Y. Seong, “Formation mechanism of cerium oxide-doped indium oxide/Ag Ohmic contacts on p-type GaN,” Appl. Phys. Lett. 89(26), 262115 (2006).
[Crossref]

Pal, S.

S. Singh, A. D. S. Nandini, S. Pal, and C. Dhanavantri, “Enhancement of light extraction efficiency of vertical LED with patterned graphene as current spreading layer,” Superlattices Microstruct. 89, 89–96 (2016).
[Crossref]

Park, C. K.

Park, J.-S.

D.-H. Kim, W. C. Lim, J.-S. Park, and T.-Y. Seong, “Highly thermally stable Pd/Zn/Ag ohmic contact to Ga-face p-type GaN,” J. Alloys Compd. 588, 327–331 (2014).
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J.-Y. Faou, G. Parry, S. Grachev, and E. Barthel, “How Does Adhesion Induce the Formation of Telephone Cord Buckles?” Phys. Rev. Lett. 108(11), 116102 (2012).
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P. Pust, P. J. Schmidt, and W. Schnick, “A revolution in lighting,” Nat. Mater. 14(5), 454–458 (2015).
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M. A. Khan, H. Chen, J. Qu, P. W. Trimby, S. Moody, Y. Yao, S. P. Ringer, and R. Zheng, “Insights into the Silver Reflection Layer of a Vertical LED for Light Emission Optimization,” ACS Appl. Mater. Interfaces 9(28), 24259–24272 (2017).
[Crossref] [PubMed]

Ringer, S. P.

M. A. Khan, H. Chen, J. Qu, P. W. Trimby, S. Moody, Y. Yao, S. P. Ringer, and R. Zheng, “Insights into the Silver Reflection Layer of a Vertical LED for Light Emission Optimization,” ACS Appl. Mater. Interfaces 9(28), 24259–24272 (2017).
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Sackovich, E. L.

V. G. Glebovsky, V. Y. Yaschak, V. V. Baranov, and E. L. Sackovich, “Properties of titanium-tungsten thin films obtained by magnetron sputtering of composite cast targets,” Thin Solid Films 257(1), 1–6 (1995).
[Crossref]

Schmidt, P. J.

P. Pust, P. J. Schmidt, and W. Schnick, “A revolution in lighting,” Nat. Mater. 14(5), 454–458 (2015).
[Crossref] [PubMed]

Schnick, W.

P. Pust, P. J. Schmidt, and W. Schnick, “A revolution in lighting,” Nat. Mater. 14(5), 454–458 (2015).
[Crossref] [PubMed]

Seong, T. Y.

Seong, T.-Y.

J. Han, D. Lee, B. Jin, H. Jeong, J.-O. Song, and T.-Y. Seong, “Optimizing n-type contact design, and chip size for high-performance indium gallium nitride/gallium nitride-based thin-film vertical light-emitting diode,” Mater. Sci. Semicond. Process. 31, 153–159 (2015).
[Crossref]

D.-H. Kim, W. C. Lim, J.-S. Park, and T.-Y. Seong, “Highly thermally stable Pd/Zn/Ag ohmic contact to Ga-face p-type GaN,” J. Alloys Compd. 588, 327–331 (2014).
[Crossref]

D.-S. Leem, T.-W. Kim, T. Lee, J.-S. Jang, Y.-W. Ok, and T.-Y. Seong, “Formation mechanism of cerium oxide-doped indium oxide/Ag Ohmic contacts on p-type GaN,” Appl. Phys. Lett. 89(26), 262115 (2006).
[Crossref]

Sharma, R.

T. Fujii, Y. Gao, R. Sharma, E. L. Hu, S. P. DenBaars, and S. Nakamura, “Increase in the extraction efficiency of GaN-based light-emitting diodes via surface roughening,” Appl. Phys. Lett. 84(6), 855–857 (2004).
[Crossref]

Sharma, V. K.

N. Hasanov, B. Zhu, V. K. Sharma, S. Lu, Y. Zhang, W. Liu, S. T. Tan, X. W. Sun, and H. V. Demir, “Improved performance of InGaN/GaN flip-chip light-emitting diodes through the use of robust Ni/Ag/TiW mirror contacts,” J. Vac. Sci. Technol. B 34(1), 011209 (2016).
[Crossref]

Singh, S.

S. Singh, A. D. S. Nandini, S. Pal, and C. Dhanavantri, “Enhancement of light extraction efficiency of vertical LED with patterned graphene as current spreading layer,” Superlattices Microstruct. 89, 89–96 (2016).
[Crossref]

Son, J. H.

Son, K.-R.

S. H. Oh, T. H. Lee, K.-R. Son, and T. G. Kim, “Fabrication of HfO2/TiO2–based conductive distributed Bragg reflectors: Its application to GaN-based near-ultraviolet micro-light-emitting diodes,” J. Alloys Compd. 773, 490–495 (2019).
[Crossref]

Song, J. O.

Song, J.-O.

J. Han, D. Lee, B. Jin, H. Jeong, J.-O. Song, and T.-Y. Seong, “Optimizing n-type contact design, and chip size for high-performance indium gallium nitride/gallium nitride-based thin-film vertical light-emitting diode,” Mater. Sci. Semicond. Process. 31, 153–159 (2015).
[Crossref]

Song, Y. H.

Sun, X. W.

N. Hasanov, B. Zhu, V. K. Sharma, S. Lu, Y. Zhang, W. Liu, S. T. Tan, X. W. Sun, and H. V. Demir, “Improved performance of InGaN/GaN flip-chip light-emitting diodes through the use of robust Ni/Ag/TiW mirror contacts,” J. Vac. Sci. Technol. B 34(1), 011209 (2016).
[Crossref]

Sung, Y. J.

Tan, S. T.

N. Hasanov, B. Zhu, V. K. Sharma, S. Lu, Y. Zhang, W. Liu, S. T. Tan, X. W. Sun, and H. V. Demir, “Improved performance of InGaN/GaN flip-chip light-emitting diodes through the use of robust Ni/Ag/TiW mirror contacts,” J. Vac. Sci. Technol. B 34(1), 011209 (2016).
[Crossref]

Tang, B.

B. Tang, J. Miao, Y. Liu, H. Wan, N. Li, S. Zhou, and C. Gui, “Enhanced Light Extraction of Flip-Chip Mini-LEDs with Prism-Structured Sidewall,” Nanomaterials (Basel) 9(3), 319 (2019).
[Crossref] [PubMed]

Taubenblatt, M. A.

M. A. Taubenblatt, D. Thomson, and C. R. Helms, “Interface effects in titanium and hafnium Schottky barriers on silicon,” Appl. Phys. Lett. 44(9), 895–897 (1984).
[Crossref]

Taylor, G. I.

A. A. Griffith and G. I. Taylor, “VI. The phenomena of rupture and flow in solids,” Philos. Trans. R. Soc. Lond. A 221(582-593), 163–198 (1921).
[Crossref]

Thomson, D.

M. A. Taubenblatt, D. Thomson, and C. R. Helms, “Interface effects in titanium and hafnium Schottky barriers on silicon,” Appl. Phys. Lett. 44(9), 895–897 (1984).
[Crossref]

Tran, C. A.

C. Chu, C. Cheng, W. Liu, J. Chu, F. Fan, H. Cheng, T. Doan, and C. A. Tran, “High Brightness GaN Vertical Light-Emitting Diodes on Metal Alloy for General Lighting Application,” Proc. IEEE 98(7), 1197–1207 (2010).
[Crossref]

Trimby, P. W.

M. A. Khan, H. Chen, J. Qu, P. W. Trimby, S. Moody, Y. Yao, S. P. Ringer, and R. Zheng, “Insights into the Silver Reflection Layer of a Vertical LED for Light Emission Optimization,” ACS Appl. Mater. Interfaces 9(28), 24259–24272 (2017).
[Crossref] [PubMed]

Tykhonov, A. N.

V. K. Malyutenko, S. S. Bolgov, and A. N. Tykhonov, “Research on Electrical Efficiency Degradation Influenced by Current Crowding in Vertical Blue InGaN-on-SiC Light-Emitting Diodes,” IEEE Photonics Technol. Lett. 24(13), 1124–1126 (2012).
[Crossref]

Volinsky, A. A.

P. Waters and A. A. Volinsky, “Stress and Moisture Effects on Thin Film Buckling Delamination,” Exp. Mech. 47(1), 163–170 (2007).
[Crossref]

Wan, H.

B. Tang, J. Miao, Y. Liu, H. Wan, N. Li, S. Zhou, and C. Gui, “Enhanced Light Extraction of Flip-Chip Mini-LEDs with Prism-Structured Sidewall,” Nanomaterials (Basel) 9(3), 319 (2019).
[Crossref] [PubMed]

Wang, C. Y.

C. C. Lee, C. Y. Wang, and G. Matijasevic, ““Au-In bonding below the eutectic temperature,” IEEE Trans. Compon., Hybrids, Manuf. Technol. 16(3), 311–316 (1993).

Wang, G.

L. Wang, E. Guo, Z. Liu, X. Yi, and G. Wang, “High-Performance Nitride Vertical Light-Emitting Diodes Based on Cu Electroplating Technical Route,” IEEE Trans. Electron Dev. 63(3), 892–902 (2016).
[Crossref]

Wang, L.

L. Wang, E. Guo, Z. Liu, X. Yi, and G. Wang, “High-Performance Nitride Vertical Light-Emitting Diodes Based on Cu Electroplating Technical Route,” IEEE Trans. Electron Dev. 63(3), 892–902 (2016).
[Crossref]

Wang, W.

H. Jia, L. Guo, W. Wang, and H. Chen, “Recent Progress in GaN-Based Light-Emitting Diodes,” Adv. Mater. 21(45), 4641–4646 (2009).
[Crossref]

Waters, P.

P. Waters and A. A. Volinsky, “Stress and Moisture Effects on Thin Film Buckling Delamination,” Exp. Mech. 47(1), 163–170 (2007).
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Figures (9)

Fig. 1
Fig. 1 Schematic illustration of the fabrication process of V-LEDs: (a) MOCVD growth of LED epitaxial layers; (b) Defining the SiO2 CBL; (c) Deposition of the metallization scheme and bonding to a Si wafer; (d) LLO to separate the sapphire substrate from the GaN epilayers; (e) ICP etching to expose the n-GaN layer; (f) Deposition of p- and n- electrodes. (g) SEM image of the exposed n-GaN surface with hemispherical dimples after LLO and ICP etching. (h) Cross-section SEM image of V-LEDs bonded on Si wafer. (i) Photograph of fabricated V-LEDs on 4-inch Si wafer.
Fig. 2
Fig. 2 (a) Cross-section TEM image of the fabricated V-LED. The red lines marked as L1 and L2 in the image denoted the EDX line scanning path. (b) The element concentration profile obtained from EDX line scanning along L1. (c) The element concentration profile obtained from EDX line scanning along L2.
Fig. 3
Fig. 3 The XPS spectra of Ga 3d core level obtained from the interface region of Ag/p-GaN samples before and after thermal annealing.
Fig. 4
Fig. 4 Optical microscope images of different metallization scheme designs suffering from moisture in the air: (a) Conventional multilayer metallization stacks without lateral protection; (b) Multilayer metallization stacks with Pt/Ti capping layers surrounding the Ag/TiW films.
Fig. 5
Fig. 5 (a) Optical microscope images of the L-LED and V-LED. (b) Simulated current density distribution in the active layers of L-LED, V-LED and V-LED with SiO2 CBL. (c) Calculated current density profiles along the dotted line in Fig. 5(b).
Fig. 6
Fig. 6 (a) SEM image of the textured surface of V-LEDs after wet etching using KOH solution. (b) SEM image of the textured surface of V-LEDs after wet etching using H3PO4 solution. (c) Simulated far-field radiation patterns of L-LEDs. (d) Simulated far-field radiation patterns of V-LEDs with integrated surface textures created by KOH wet etching.
Fig. 7
Fig. 7 (a) I-V profiles of fabricated L-LEDs and V-LEDs. (b) L-I characteristics of the fabricated L-LEDs and V-LEDs.
Fig. 8
Fig. 8 LOP maintenance of V-LEDs after prolonged high temperature–humidity aging test.
Fig. 9
Fig. 9 (a) I-V characteristics of ITO contact to p-GaN, Ag/TiW contact to p-GaN. (b) I-V characteristics of Cr/Pt/Au to n-GaN.

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