Abstract

High-power flip-chip light-emitting diodes (FCLEDs) suffer from low efficiencies because of poor p-type reflective ohmic contact and severe current crowding. Here, we show that it is possible to improve both the light extraction efficiency (LEE) and current spreading of an FCLED by incorporating a highly reflective metallic reflector made from silver (Ag). The reflector, which consists of an Ag film covered by three pairs of TiW/Pt multilayers, demonstrates high reflectance of 95.0% at 460 nm at arbitrary angles of incidence. Our numerical simulation and experimental results reveal that the FCLED with Ag-based reflector exhibits higher LEE and better current spreading than the FCLED with indium-tin oxide (ITO)/distributed Bragg reflector (DBR). As a result, the external quantum efficiency (EQE) of FCLED with Ag-based reflector was 6.0% higher than that of FCLED with ITO/DBR at 750 mA injection current. Our work also suggests that the EQE of FCLED with the Ag-based reflector could be further enhanced 5.2% by replacing the finger-like n-electrodes with three-dimensional (3D) vias n-electrodes, which spread the injection current uniformly over the entire light-emitting active region. This study paves the way towards higher-performance LED technology.

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

Full Article  |  PDF Article
OSA Recommended Articles
Numerical and experimental investigation of GaN-based flip-chip light-emitting diodes with highly reflective Ag/TiW and ITO/DBR Ohmic contacts

Shengjun Zhou, Xingtong Liu, Yilin Gao, Yingce Liu, Mengling Liu, Zongyuan Liu, Chengqun Gui, and Sheng Liu
Opt. Express 25(22) 26615-26627 (2017)

Numerical simulation and experimental investigation of GaN-based flip-chip LEDs and top-emitting LEDs

Xingtong Liu, Shengjun Zhou, Yilin Gao, Hongpo Hu, Yingce Liu, Chengqun Gui, and Sheng Liu
Appl. Opt. 56(34) 9502-9509 (2017)

High performance GaN-based flip-chip LEDs with different electrode patterns

Ray-Hua Horng, Shih-Hao Chuang, Ching-Ho Tien, Sin-Cyuan Lin, and Dong-Sing Wuu
Opt. Express 22(S3) A941-A946 (2014)

References

  • View by:
  • |
  • |
  • |

  1. S. Liu and X. Luo, LED packaging for lighting applications: design, manufacturing, and testing (John Wiley & Sons, 2011).
  2. F. A. Ponce and D. P. Bour, “Nitride-based semiconductors for blue and green light-emitting devices,” Nature 386(6623), 351–359 (1997).
    [Crossref]
  3. E. F. Schubert and J. K. Kim, “Solid-state light sources getting smart,” Science 308(5726), 1274–1278 (2005).
    [Crossref] [PubMed]
  4. A. David, T. Fujii, R. Sharma, K. McGroddy, S. Nakamura, S. P. DenBaars, E. L. Hu, C. Weisbuch, and H. Benisty, “Photonic-crystal GaN light-emitting diodes with tailored guided modes distribution,” Appl. Phys. Lett. 88(6), 061124 (2006).
    [Crossref]
  5. S. Pimputkar, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Prospects for LED lighting,” Nat. Photonics 3(4), 180–182 (2009).
    [Crossref]
  6. N. Han, T. V. Cuong, M. Han, B. D. Ryu, S. Chandramohan, J. B. Park, J. H. Kang, Y. J. Park, K. B. Ko, H. Y. Kim, H. K. Kim, J. H. Ryu, Y. S. Katharria, C. J. Choi, and C. H. Hong, “Improved heat dissipation in gallium nitride light-emitting diodes with embedded graphene oxide pattern,” Nat. Commun. 4, 1452 (2013).
    [Crossref] [PubMed]
  7. J. J. Wierer, A. David, and M. M. Megens, “III-nitride photonic-crystal light-emitting diodes with high extraction efficiency,” Nat. Photonics 3(3), 163–169 (2009).
    [Crossref]
  8. H. Hu, S. Zhou, X. Liu, Y. Gao, C. Gui, and S. Liu, “Effects of GaN/AlGaN/Sputtered AlN nucleation layers on performance of GaN-based ultraviolet light-emitting diodes,” Sci. Rep. 7(1), 44627 (2017).
    [Crossref] [PubMed]
  9. J. J. Wierer, D. A. Steigerwald, M. R. Krames, J. J. O’Shea, M. J. Ludowise, G. Christenson, Y.-C. Shen, C. Lowery, P. S. Martin, S. Subramanya, W. Götz, N. F. Gardner, R. S. Kern, and S. A. Stockman, “High-power AlGaInN flip-chip light-emitting diodes,” Appl. Phys. Lett. 78(22), 3379–3381 (2001).
    [Crossref]
  10. B. P. Yonkee, E. C. Young, S. P. DenBaars, S. Nakamura, and J. S. Speck, “Silver free III-nitride flip chip light emitting-diode with wall plug efficiency over 70% utilizing a GaN tunnel junction,” Appl. Phys. Lett. 109(19), 191104 (2016).
    [Crossref] [PubMed]
  11. O. B. Shchekin, J. E. Epler, T. A. Trottier, T. Margalith, D. A. Steigerwald, M. O. Holcomb, P. S. Martin, and M. R. Krames, “High performance thin-film flip-chip InGaN-GaN light-emitting diodes,” Appl. Phys. Lett. 89(7), 071109 (2006).
    [Crossref]
  12. M. Shatalov and A. Chitnisl, “Thermal analysis of flip-chip packaged 280 nm nitride-based deep ultraviolet light-emitting diodes,” Appl. Phys. Lett. 86(20), 2201109 (2016).
  13. C. H. Lin, C. F. Lai, T. S. Ko, H. W. Huang, H. C. Kuo, Y. Y. Hung, K. M. Leung, C. C. Yu, R. J. Tsai, C. K. Lee, T. C. Lu, and S. C. Wang, “Enhancement of InGaN–GaN Indium-Tin-Oxide Flip-Chip Light-Emitting Diodes With TiO2-SiO2 Multilayer Stack Omnidirectional Reflector,” IEEE Photonics Technol. Lett. 18(19), 2050–2052 (2006).
    [Crossref]
  14. X. Liu, S. Zhou, Y. Gao, H. Hu, Y. Liu, C. Gui, and S. Liu, “Numerical simulation and experimental investigation of GaN-based flip-chip LEDs and top-emitting LEDs,” Appl. Opt. 56(34), 9502–9509 (2017).
    [Crossref] [PubMed]
  15. S. Zhou, H. Xu, M. Liu, X. Liu, J. Zhao, N. Li, and S. Liu, “Effect of Dielectric Distributed Bragg Reflector on Electrical and Optical Properties of GaN-Based Flip-Chip Light-Emitting Diodes,” Micromachines (Basel) 9(12), 650 (2018).
    [Crossref] [PubMed]
  16. 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]
  17. K. P. Hsueh, K. C. Chiang, Y. M. Hsin, and C. J. Wang, “Investigation of Cr-and Al-based metals for the reflector and Ohmic contact on n-GaN in GaN flip-chip light-emitting diodes,” Appl. Phys. Lett. 89(19), 191122 (2006).
    [Crossref]
  18. J.-Y. Kim, M.-K. Kwon, I.-K. Park, C.-Y. Cho, S.-J. Park, D.-M. Jeon, J. W. Kim, and Y. C. Kim, “Enhanced light extraction efficiency in flip-chip GaN light-emitting diodes with diffuse Ag reflector on nanotextured indium-tin oxide,” Appl. Phys. Lett. 93(2), 021121 (2008).
    [Crossref]
  19. X. Liu, N. Li, J. Hu, Y. Gao, R. Wang, and S. Zhou, “Comparative Study of Highly Reflective ITO/DBR and Ni/Ag ohmic Contacts for GaN-Based Flip-Chip Light-Emitting Diodes,” ECS J. Solid State Sci. Technol. 7(6), Q116–Q122 (2018).
    [Crossref]
  20. T. H. Park, T. H. Lee, and T. G. Kim, “Al2O3/AlN/Al-based backside diffuse reflector for high-brightness 370-nm AlGaN ultraviolet light-emitting diodes,” J. Alloys Compd. 776, 1009–1015 (2019).
    [Crossref]
  21. N. Maeda, J. Yun, M. Jo, and H. Hirayama, “Enhancing the light-extraction efficiency of AlGaN deep-ultraviolet light-emitting diodes using highly reflective Ni/Mg and Rh as p-type electrodes,” Jpn. J. Appl. Phys. 57(4S), 04FH08 (2018).
    [Crossref]
  22. J. O. Song, J. S. Kwak, Y. Park, and T. Y. Seong, “Ohmic and degradation mechanisms of Ag contacts on p-type GaN,” Appl. Phys. Lett. 86(6), 062104 (2005).
    [Crossref]
  23. J. H. Son, Y. H. Song, H. K. Yu, and J. L. Lee, “Effects of Ni cladding layers on suppression of Ag agglomeration in Ag-based Ohmic contacts on p-GaN,” Appl. Phys. Lett. 95(6), 062108 (2009).
    [Crossref]
  24. J. Lv, C. Zheng, Q. Chen, S. Zhou, and S. Liu, “High power InGaN/GaN flip-chip LEDs with via-hole-based two-level metallization electrodes,” Phys. Status Solidi., A Appl. Mater. Sci. 213(12), 3150–3156 (2016).
    [Crossref]
  25. S. Zhou, X. Liu, Y. Gao, Y. Liu, M. Liu, Z. Liu, C. Gui, and S. Liu, “Numerical and experimental investigation of GaN-based flip-chip light-emitting diodes with highly reflective Ag/TiW and ITO/DBR Ohmic contacts,” Opt. Express 25(22), 26615–26627 (2017).
    [Crossref] [PubMed]
  26. X. Guo and E. F. Schubert, “Current crowding and optical saturation effects in GaInN/GaN light-emitting diodes grown on insulating substrates,” Appl. Phys. Lett. 78(21), 3337–3339 (2001).
    [Crossref]
  27. I. Eliashevich, Y. Li, A. Osinsky, C. A. Tran, M. G. Brown, and R. F. Karlicek, “InGaN blue light-emitting diodes with optimized n-GaN layer,” Proc. SPIE 3621, 28–36 (1999).
    [Crossref]
  28. J. K. Sheu and G. C. Chi, “The doping process and dopant characteristics of GaN,” J. Phys. Condens. Matter 14(22), R657 (2002).
    [Crossref]
  29. S. Hwang and J. Shim, “A method for current spreading analysis and electrode pattern design in light-emitting diodes,” IEEE Trans. Electron Dev. 55(5), 1123–1128 (2008).
    [Crossref]
  30. W. C. Chong and K. M. Lau, “Performance enhancements of flip-chip light-emitting diodes with high-density n-type point-contacts,” IEEE Electron Device Lett. 35(10), 1049–1051 (2014).
    [Crossref]
  31. P. E. Blöchl, “Projector augmented-wave method,” Phys. Rev. B Condens. Matter 50(24), 17953–17979 (1994).
    [Crossref] [PubMed]
  32. J. P. Perdew, K. Burke, and M. Ernzerhof, “Generalized gradient approximation made simple,” Phys. Rev. Lett. 77(18), 3865–3868 (1996).
    [Crossref] [PubMed]
  33. K. O. Kese, Z. C. Li, and B. Bergman, “Influence of residual stress on elastic modulus and hardness of soda-lime glass measured by nanoindentation,” J. Mater. Res. 19(10), 3109–3119 (2004).
    [Crossref]
  34. T. Y. Tsui, W. C. Oliver, and G. M. Pharr, “Influences of stress on the measurement of mechanical properties using nanoindentation: Part I. Experimental studies in an aluminum alloy,” J. Mater. Res. 11, 752–759 (1996).
    [Crossref]
  35. 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]
  36. R. T. Tung, “The physics and chemistry of the Schottky barrier height,” Appl. Phys. Lett. 1(1), 011304 (2014).
  37. A. Baldereschi, S. Baroni, and R. Resta, “Band Offsets in Lattice-Matched Heterojunctions: A Model and First-Principles Calculations for GaAs/AlAs,” Phys. Rev. Lett. 61(6), 734–737 (1988).
    [Crossref] [PubMed]
  38. K. T. Delaney, N. A. Spaldin, and C. G. Van de Walle, “Theoretical study of Schottky-barrier formation at epitaxial rare-earth-metal/semiconductor interfaces,” Phys. Rev. B Condens. Matter Mater. Phys. 81(16), 165312 (2010).
    [Crossref]
  39. H. Zhao, G. Liu, R. A. Arif, and N. Tansu, “Current injection efficiency induced efficiency-droop in InGaN quantum well light-emitting diodes,” Solid-State Electron. 54(10), 1119–1124 (2010).
    [Crossref]
  40. D. A. Zakheim, A. S. Pavluchenko, D. A. Bauman, K. A. Bulashevich, O. V. Khokhlev, and S. Y. Karpov, “Efficiency droop suppression in InGaN-based blue LEDs: Experiment and numerical modelling,” Phys. Status Solidi., A Appl. Mater. Sci. 209(3), 456–460 (2012).
    [Crossref]
  41. H. Y. Ryu and J. I. Shim, “Effect of current spreading on the efficiency droop of InGaN light-emitting diodes,” Opt. Express 19(4), 2886–2894 (2011).
    [Crossref] [PubMed]
  42. S. Suresh and A. E. Giannakopoulos, “A new method for estimating residual stresses by instrumented sharp indentation,” Acta Mater. 46(16), 5755–5767 (1998).
    [Crossref]
  43. L. N. Zhu, B. S. Xu, H. D. Wang, and C. B. Wang, “Measurement of residual stress in quenched 1045 steel by the nanoindentation method,” Mater. Charact. 61(12), 1359–1362 (2010).
    [Crossref]
  44. S. Carlsson and P. L. Larsson, “On the determination of residual stress and strain fields by sharp indentation testing: Part I. theoretical and numerical analysis,” Acta Mater. 49(12), 2179–2191 (2001).
    [Crossref]
  45. S. Carlsson and P. L. Larsson, “On the determination of residual stress and strain fields by sharp indentation testing: Part II. experimental investigation,” Acta Mater. 49(12), 2193–2203 (2001).
    [Crossref]
  46. Y. H. Lee and D. Kwon, “Measurement of residual-stress effect by nanoindentation on elastically strained (100) W,” Scr. Mater. 49(5), 459–465 (2003).
    [Crossref]
  47. Y. H. Lee and D. Kwon, “Residual stresses in DLC/Si and Au/Si systems: Application of a stress-relaxation model to the nanoindentation technique,” J. Mater. Res. 17, 901–906 (2002).
    [Crossref]
  48. T. Y. Tsui, W. C. Oliver, and G. M. Pharr, “Influences of stress on the measurement of mechanical properties using nanoindentation: Part I. Experimental studies in an aluminum alloy,” J. Mater. Res. 11(03), 752–759 (1996).
    [Crossref]
  49. A. Bolshakov, W. C. Oliver, and G. M. Pharr, “Influences of stress on the measurement of mechanical properties using nanoindentation: Part II. Finite element simulations,” J. Mater. Res. 11(03), 760–768 (1996).
    [Crossref]

2019 (2)

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]

T. H. Park, T. H. Lee, and T. G. Kim, “Al2O3/AlN/Al-based backside diffuse reflector for high-brightness 370-nm AlGaN ultraviolet light-emitting diodes,” J. Alloys Compd. 776, 1009–1015 (2019).
[Crossref]

2018 (3)

N. Maeda, J. Yun, M. Jo, and H. Hirayama, “Enhancing the light-extraction efficiency of AlGaN deep-ultraviolet light-emitting diodes using highly reflective Ni/Mg and Rh as p-type electrodes,” Jpn. J. Appl. Phys. 57(4S), 04FH08 (2018).
[Crossref]

X. Liu, N. Li, J. Hu, Y. Gao, R. Wang, and S. Zhou, “Comparative Study of Highly Reflective ITO/DBR and Ni/Ag ohmic Contacts for GaN-Based Flip-Chip Light-Emitting Diodes,” ECS J. Solid State Sci. Technol. 7(6), Q116–Q122 (2018).
[Crossref]

S. Zhou, H. Xu, M. Liu, X. Liu, J. Zhao, N. Li, and S. Liu, “Effect of Dielectric Distributed Bragg Reflector on Electrical and Optical Properties of GaN-Based Flip-Chip Light-Emitting Diodes,” Micromachines (Basel) 9(12), 650 (2018).
[Crossref] [PubMed]

2017 (4)

X. Liu, S. Zhou, Y. Gao, H. Hu, Y. Liu, C. Gui, and S. Liu, “Numerical simulation and experimental investigation of GaN-based flip-chip LEDs and top-emitting LEDs,” Appl. Opt. 56(34), 9502–9509 (2017).
[Crossref] [PubMed]

H. Hu, S. Zhou, X. Liu, Y. Gao, C. Gui, and S. Liu, “Effects of GaN/AlGaN/Sputtered AlN nucleation layers on performance of GaN-based ultraviolet light-emitting diodes,” Sci. Rep. 7(1), 44627 (2017).
[Crossref] [PubMed]

S. Zhou, X. Liu, Y. Gao, Y. Liu, M. Liu, Z. Liu, C. Gui, and S. Liu, “Numerical and experimental investigation of GaN-based flip-chip light-emitting diodes with highly reflective Ag/TiW and ITO/DBR Ohmic contacts,” Opt. Express 25(22), 26615–26627 (2017).
[Crossref] [PubMed]

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)

J. Lv, C. Zheng, Q. Chen, S. Zhou, and S. Liu, “High power InGaN/GaN flip-chip LEDs with via-hole-based two-level metallization electrodes,” Phys. Status Solidi., A Appl. Mater. Sci. 213(12), 3150–3156 (2016).
[Crossref]

B. P. Yonkee, E. C. Young, S. P. DenBaars, S. Nakamura, and J. S. Speck, “Silver free III-nitride flip chip light emitting-diode with wall plug efficiency over 70% utilizing a GaN tunnel junction,” Appl. Phys. Lett. 109(19), 191104 (2016).
[Crossref] [PubMed]

M. Shatalov and A. Chitnisl, “Thermal analysis of flip-chip packaged 280 nm nitride-based deep ultraviolet light-emitting diodes,” Appl. Phys. Lett. 86(20), 2201109 (2016).

2014 (2)

R. T. Tung, “The physics and chemistry of the Schottky barrier height,” Appl. Phys. Lett. 1(1), 011304 (2014).

W. C. Chong and K. M. Lau, “Performance enhancements of flip-chip light-emitting diodes with high-density n-type point-contacts,” IEEE Electron Device Lett. 35(10), 1049–1051 (2014).
[Crossref]

2013 (1)

N. Han, T. V. Cuong, M. Han, B. D. Ryu, S. Chandramohan, J. B. Park, J. H. Kang, Y. J. Park, K. B. Ko, H. Y. Kim, H. K. Kim, J. H. Ryu, Y. S. Katharria, C. J. Choi, and C. H. Hong, “Improved heat dissipation in gallium nitride light-emitting diodes with embedded graphene oxide pattern,” Nat. Commun. 4, 1452 (2013).
[Crossref] [PubMed]

2012 (1)

D. A. Zakheim, A. S. Pavluchenko, D. A. Bauman, K. A. Bulashevich, O. V. Khokhlev, and S. Y. Karpov, “Efficiency droop suppression in InGaN-based blue LEDs: Experiment and numerical modelling,” Phys. Status Solidi., A Appl. Mater. Sci. 209(3), 456–460 (2012).
[Crossref]

2011 (1)

2010 (3)

K. T. Delaney, N. A. Spaldin, and C. G. Van de Walle, “Theoretical study of Schottky-barrier formation at epitaxial rare-earth-metal/semiconductor interfaces,” Phys. Rev. B Condens. Matter Mater. Phys. 81(16), 165312 (2010).
[Crossref]

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

L. N. Zhu, B. S. Xu, H. D. Wang, and C. B. Wang, “Measurement of residual stress in quenched 1045 steel by the nanoindentation method,” Mater. Charact. 61(12), 1359–1362 (2010).
[Crossref]

2009 (3)

J. J. Wierer, A. David, and M. M. Megens, “III-nitride photonic-crystal light-emitting diodes with high extraction efficiency,” Nat. Photonics 3(3), 163–169 (2009).
[Crossref]

S. Pimputkar, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Prospects for LED lighting,” Nat. Photonics 3(4), 180–182 (2009).
[Crossref]

J. H. Son, Y. H. Song, H. K. Yu, and J. L. Lee, “Effects of Ni cladding layers on suppression of Ag agglomeration in Ag-based Ohmic contacts on p-GaN,” Appl. Phys. Lett. 95(6), 062108 (2009).
[Crossref]

2008 (2)

J.-Y. Kim, M.-K. Kwon, I.-K. Park, C.-Y. Cho, S.-J. Park, D.-M. Jeon, J. W. Kim, and Y. C. Kim, “Enhanced light extraction efficiency in flip-chip GaN light-emitting diodes with diffuse Ag reflector on nanotextured indium-tin oxide,” Appl. Phys. Lett. 93(2), 021121 (2008).
[Crossref]

S. Hwang and J. Shim, “A method for current spreading analysis and electrode pattern design in light-emitting diodes,” IEEE Trans. Electron Dev. 55(5), 1123–1128 (2008).
[Crossref]

2006 (4)

A. David, T. Fujii, R. Sharma, K. McGroddy, S. Nakamura, S. P. DenBaars, E. L. Hu, C. Weisbuch, and H. Benisty, “Photonic-crystal GaN light-emitting diodes with tailored guided modes distribution,” Appl. Phys. Lett. 88(6), 061124 (2006).
[Crossref]

C. H. Lin, C. F. Lai, T. S. Ko, H. W. Huang, H. C. Kuo, Y. Y. Hung, K. M. Leung, C. C. Yu, R. J. Tsai, C. K. Lee, T. C. Lu, and S. C. Wang, “Enhancement of InGaN–GaN Indium-Tin-Oxide Flip-Chip Light-Emitting Diodes With TiO2-SiO2 Multilayer Stack Omnidirectional Reflector,” IEEE Photonics Technol. Lett. 18(19), 2050–2052 (2006).
[Crossref]

O. B. Shchekin, J. E. Epler, T. A. Trottier, T. Margalith, D. A. Steigerwald, M. O. Holcomb, P. S. Martin, and M. R. Krames, “High performance thin-film flip-chip InGaN-GaN light-emitting diodes,” Appl. Phys. Lett. 89(7), 071109 (2006).
[Crossref]

K. P. Hsueh, K. C. Chiang, Y. M. Hsin, and C. J. Wang, “Investigation of Cr-and Al-based metals for the reflector and Ohmic contact on n-GaN in GaN flip-chip light-emitting diodes,” Appl. Phys. Lett. 89(19), 191122 (2006).
[Crossref]

2005 (2)

E. F. Schubert and J. K. Kim, “Solid-state light sources getting smart,” Science 308(5726), 1274–1278 (2005).
[Crossref] [PubMed]

J. O. Song, J. S. Kwak, Y. Park, and T. Y. Seong, “Ohmic and degradation mechanisms of Ag contacts on p-type GaN,” Appl. Phys. Lett. 86(6), 062104 (2005).
[Crossref]

2004 (1)

K. O. Kese, Z. C. Li, and B. Bergman, “Influence of residual stress on elastic modulus and hardness of soda-lime glass measured by nanoindentation,” J. Mater. Res. 19(10), 3109–3119 (2004).
[Crossref]

2003 (1)

Y. H. Lee and D. Kwon, “Measurement of residual-stress effect by nanoindentation on elastically strained (100) W,” Scr. Mater. 49(5), 459–465 (2003).
[Crossref]

2002 (2)

Y. H. Lee and D. Kwon, “Residual stresses in DLC/Si and Au/Si systems: Application of a stress-relaxation model to the nanoindentation technique,” J. Mater. Res. 17, 901–906 (2002).
[Crossref]

J. K. Sheu and G. C. Chi, “The doping process and dopant characteristics of GaN,” J. Phys. Condens. Matter 14(22), R657 (2002).
[Crossref]

2001 (4)

X. Guo and E. F. Schubert, “Current crowding and optical saturation effects in GaInN/GaN light-emitting diodes grown on insulating substrates,” Appl. Phys. Lett. 78(21), 3337–3339 (2001).
[Crossref]

J. J. Wierer, D. A. Steigerwald, M. R. Krames, J. J. O’Shea, M. J. Ludowise, G. Christenson, Y.-C. Shen, C. Lowery, P. S. Martin, S. Subramanya, W. Götz, N. F. Gardner, R. S. Kern, and S. A. Stockman, “High-power AlGaInN flip-chip light-emitting diodes,” Appl. Phys. Lett. 78(22), 3379–3381 (2001).
[Crossref]

S. Carlsson and P. L. Larsson, “On the determination of residual stress and strain fields by sharp indentation testing: Part I. theoretical and numerical analysis,” Acta Mater. 49(12), 2179–2191 (2001).
[Crossref]

S. Carlsson and P. L. Larsson, “On the determination of residual stress and strain fields by sharp indentation testing: Part II. experimental investigation,” Acta Mater. 49(12), 2193–2203 (2001).
[Crossref]

1999 (1)

I. Eliashevich, Y. Li, A. Osinsky, C. A. Tran, M. G. Brown, and R. F. Karlicek, “InGaN blue light-emitting diodes with optimized n-GaN layer,” Proc. SPIE 3621, 28–36 (1999).
[Crossref]

1998 (1)

S. Suresh and A. E. Giannakopoulos, “A new method for estimating residual stresses by instrumented sharp indentation,” Acta Mater. 46(16), 5755–5767 (1998).
[Crossref]

1997 (1)

F. A. Ponce and D. P. Bour, “Nitride-based semiconductors for blue and green light-emitting devices,” Nature 386(6623), 351–359 (1997).
[Crossref]

1996 (4)

T. Y. Tsui, W. C. Oliver, and G. M. Pharr, “Influences of stress on the measurement of mechanical properties using nanoindentation: Part I. Experimental studies in an aluminum alloy,” J. Mater. Res. 11, 752–759 (1996).
[Crossref]

T. Y. Tsui, W. C. Oliver, and G. M. Pharr, “Influences of stress on the measurement of mechanical properties using nanoindentation: Part I. Experimental studies in an aluminum alloy,” J. Mater. Res. 11(03), 752–759 (1996).
[Crossref]

A. Bolshakov, W. C. Oliver, and G. M. Pharr, “Influences of stress on the measurement of mechanical properties using nanoindentation: Part II. Finite element simulations,” J. Mater. Res. 11(03), 760–768 (1996).
[Crossref]

J. P. Perdew, K. Burke, and M. Ernzerhof, “Generalized gradient approximation made simple,” Phys. Rev. Lett. 77(18), 3865–3868 (1996).
[Crossref] [PubMed]

1994 (1)

P. E. Blöchl, “Projector augmented-wave method,” Phys. Rev. B Condens. Matter 50(24), 17953–17979 (1994).
[Crossref] [PubMed]

1988 (1)

A. Baldereschi, S. Baroni, and R. Resta, “Band Offsets in Lattice-Matched Heterojunctions: A Model and First-Principles Calculations for GaAs/AlAs,” Phys. Rev. Lett. 61(6), 734–737 (1988).
[Crossref] [PubMed]

Arif, R. A.

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

Baldereschi, A.

A. Baldereschi, S. Baroni, and R. Resta, “Band Offsets in Lattice-Matched Heterojunctions: A Model and First-Principles Calculations for GaAs/AlAs,” Phys. Rev. Lett. 61(6), 734–737 (1988).
[Crossref] [PubMed]

Baroni, S.

A. Baldereschi, S. Baroni, and R. Resta, “Band Offsets in Lattice-Matched Heterojunctions: A Model and First-Principles Calculations for GaAs/AlAs,” Phys. Rev. Lett. 61(6), 734–737 (1988).
[Crossref] [PubMed]

Bauman, D. A.

D. A. Zakheim, A. S. Pavluchenko, D. A. Bauman, K. A. Bulashevich, O. V. Khokhlev, and S. Y. Karpov, “Efficiency droop suppression in InGaN-based blue LEDs: Experiment and numerical modelling,” Phys. Status Solidi., A Appl. Mater. Sci. 209(3), 456–460 (2012).
[Crossref]

Benisty, H.

A. David, T. Fujii, R. Sharma, K. McGroddy, S. Nakamura, S. P. DenBaars, E. L. Hu, C. Weisbuch, and H. Benisty, “Photonic-crystal GaN light-emitting diodes with tailored guided modes distribution,” Appl. Phys. Lett. 88(6), 061124 (2006).
[Crossref]

Bergman, B.

K. O. Kese, Z. C. Li, and B. Bergman, “Influence of residual stress on elastic modulus and hardness of soda-lime glass measured by nanoindentation,” J. Mater. Res. 19(10), 3109–3119 (2004).
[Crossref]

Blöchl, P. E.

P. E. Blöchl, “Projector augmented-wave method,” Phys. Rev. B Condens. Matter 50(24), 17953–17979 (1994).
[Crossref] [PubMed]

Bolshakov, A.

A. Bolshakov, W. C. Oliver, and G. M. Pharr, “Influences of stress on the measurement of mechanical properties using nanoindentation: Part II. Finite element simulations,” J. Mater. Res. 11(03), 760–768 (1996).
[Crossref]

Bour, D. P.

F. A. Ponce and D. P. Bour, “Nitride-based semiconductors for blue and green light-emitting devices,” Nature 386(6623), 351–359 (1997).
[Crossref]

Brown, M. G.

I. Eliashevich, Y. Li, A. Osinsky, C. A. Tran, M. G. Brown, and R. F. Karlicek, “InGaN blue light-emitting diodes with optimized n-GaN layer,” Proc. SPIE 3621, 28–36 (1999).
[Crossref]

Bulashevich, K. A.

D. A. Zakheim, A. S. Pavluchenko, D. A. Bauman, K. A. Bulashevich, O. V. Khokhlev, and S. Y. Karpov, “Efficiency droop suppression in InGaN-based blue LEDs: Experiment and numerical modelling,” Phys. Status Solidi., A Appl. Mater. Sci. 209(3), 456–460 (2012).
[Crossref]

Burke, K.

J. P. Perdew, K. Burke, and M. Ernzerhof, “Generalized gradient approximation made simple,” Phys. Rev. Lett. 77(18), 3865–3868 (1996).
[Crossref] [PubMed]

Carlsson, S.

S. Carlsson and P. L. Larsson, “On the determination of residual stress and strain fields by sharp indentation testing: Part I. theoretical and numerical analysis,” Acta Mater. 49(12), 2179–2191 (2001).
[Crossref]

S. Carlsson and P. L. Larsson, “On the determination of residual stress and strain fields by sharp indentation testing: Part II. experimental investigation,” Acta Mater. 49(12), 2193–2203 (2001).
[Crossref]

Chandramohan, S.

N. Han, T. V. Cuong, M. Han, B. D. Ryu, S. Chandramohan, J. B. Park, J. H. Kang, Y. J. Park, K. B. Ko, H. Y. Kim, H. K. Kim, J. H. Ryu, Y. S. Katharria, C. J. Choi, and C. H. Hong, “Improved heat dissipation in gallium nitride light-emitting diodes with embedded graphene oxide pattern,” Nat. Commun. 4, 1452 (2013).
[Crossref] [PubMed]

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]

Chen, Q.

J. Lv, C. Zheng, Q. Chen, S. Zhou, and S. Liu, “High power InGaN/GaN flip-chip LEDs with via-hole-based two-level metallization electrodes,” Phys. Status Solidi., A Appl. Mater. Sci. 213(12), 3150–3156 (2016).
[Crossref]

Chi, G. C.

J. K. Sheu and G. C. Chi, “The doping process and dopant characteristics of GaN,” J. Phys. Condens. Matter 14(22), R657 (2002).
[Crossref]

Chiang, K. C.

K. P. Hsueh, K. C. Chiang, Y. M. Hsin, and C. J. Wang, “Investigation of Cr-and Al-based metals for the reflector and Ohmic contact on n-GaN in GaN flip-chip light-emitting diodes,” Appl. Phys. Lett. 89(19), 191122 (2006).
[Crossref]

Chitnisl, A.

M. Shatalov and A. Chitnisl, “Thermal analysis of flip-chip packaged 280 nm nitride-based deep ultraviolet light-emitting diodes,” Appl. Phys. Lett. 86(20), 2201109 (2016).

Cho, C.-Y.

J.-Y. Kim, M.-K. Kwon, I.-K. Park, C.-Y. Cho, S.-J. Park, D.-M. Jeon, J. W. Kim, and Y. C. Kim, “Enhanced light extraction efficiency in flip-chip GaN light-emitting diodes with diffuse Ag reflector on nanotextured indium-tin oxide,” Appl. Phys. Lett. 93(2), 021121 (2008).
[Crossref]

Choi, C. J.

N. Han, T. V. Cuong, M. Han, B. D. Ryu, S. Chandramohan, J. B. Park, J. H. Kang, Y. J. Park, K. B. Ko, H. Y. Kim, H. K. Kim, J. H. Ryu, Y. S. Katharria, C. J. Choi, and C. H. Hong, “Improved heat dissipation in gallium nitride light-emitting diodes with embedded graphene oxide pattern,” Nat. Commun. 4, 1452 (2013).
[Crossref] [PubMed]

Chong, W. C.

W. C. Chong and K. M. Lau, “Performance enhancements of flip-chip light-emitting diodes with high-density n-type point-contacts,” IEEE Electron Device Lett. 35(10), 1049–1051 (2014).
[Crossref]

Christenson, G.

J. J. Wierer, D. A. Steigerwald, M. R. Krames, J. J. O’Shea, M. J. Ludowise, G. Christenson, Y.-C. Shen, C. Lowery, P. S. Martin, S. Subramanya, W. Götz, N. F. Gardner, R. S. Kern, and S. A. Stockman, “High-power AlGaInN flip-chip light-emitting diodes,” Appl. Phys. Lett. 78(22), 3379–3381 (2001).
[Crossref]

Cuong, T. V.

N. Han, T. V. Cuong, M. Han, B. D. Ryu, S. Chandramohan, J. B. Park, J. H. Kang, Y. J. Park, K. B. Ko, H. Y. Kim, H. K. Kim, J. H. Ryu, Y. S. Katharria, C. J. Choi, and C. H. Hong, “Improved heat dissipation in gallium nitride light-emitting diodes with embedded graphene oxide pattern,” Nat. Commun. 4, 1452 (2013).
[Crossref] [PubMed]

David, A.

J. J. Wierer, A. David, and M. M. Megens, “III-nitride photonic-crystal light-emitting diodes with high extraction efficiency,” Nat. Photonics 3(3), 163–169 (2009).
[Crossref]

A. David, T. Fujii, R. Sharma, K. McGroddy, S. Nakamura, S. P. DenBaars, E. L. Hu, C. Weisbuch, and H. Benisty, “Photonic-crystal GaN light-emitting diodes with tailored guided modes distribution,” Appl. Phys. Lett. 88(6), 061124 (2006).
[Crossref]

Delaney, K. T.

K. T. Delaney, N. A. Spaldin, and C. G. Van de Walle, “Theoretical study of Schottky-barrier formation at epitaxial rare-earth-metal/semiconductor interfaces,” Phys. Rev. B Condens. Matter Mater. Phys. 81(16), 165312 (2010).
[Crossref]

DenBaars, S. P.

B. P. Yonkee, E. C. Young, S. P. DenBaars, S. Nakamura, and J. S. Speck, “Silver free III-nitride flip chip light emitting-diode with wall plug efficiency over 70% utilizing a GaN tunnel junction,” Appl. Phys. Lett. 109(19), 191104 (2016).
[Crossref] [PubMed]

S. Pimputkar, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Prospects for LED lighting,” Nat. Photonics 3(4), 180–182 (2009).
[Crossref]

A. David, T. Fujii, R. Sharma, K. McGroddy, S. Nakamura, S. P. DenBaars, E. L. Hu, C. Weisbuch, and H. Benisty, “Photonic-crystal GaN light-emitting diodes with tailored guided modes distribution,” Appl. Phys. Lett. 88(6), 061124 (2006).
[Crossref]

Eliashevich, I.

I. Eliashevich, Y. Li, A. Osinsky, C. A. Tran, M. G. Brown, and R. F. Karlicek, “InGaN blue light-emitting diodes with optimized n-GaN layer,” Proc. SPIE 3621, 28–36 (1999).
[Crossref]

Epler, J. E.

O. B. Shchekin, J. E. Epler, T. A. Trottier, T. Margalith, D. A. Steigerwald, M. O. Holcomb, P. S. Martin, and M. R. Krames, “High performance thin-film flip-chip InGaN-GaN light-emitting diodes,” Appl. Phys. Lett. 89(7), 071109 (2006).
[Crossref]

Ernzerhof, M.

J. P. Perdew, K. Burke, and M. Ernzerhof, “Generalized gradient approximation made simple,” Phys. Rev. Lett. 77(18), 3865–3868 (1996).
[Crossref] [PubMed]

Fujii, T.

A. David, T. Fujii, R. Sharma, K. McGroddy, S. Nakamura, S. P. DenBaars, E. L. Hu, C. Weisbuch, and H. Benisty, “Photonic-crystal GaN light-emitting diodes with tailored guided modes distribution,” Appl. Phys. Lett. 88(6), 061124 (2006).
[Crossref]

Gao, Y.

X. Liu, N. Li, J. Hu, Y. Gao, R. Wang, and S. Zhou, “Comparative Study of Highly Reflective ITO/DBR and Ni/Ag ohmic Contacts for GaN-Based Flip-Chip Light-Emitting Diodes,” ECS J. Solid State Sci. Technol. 7(6), Q116–Q122 (2018).
[Crossref]

H. Hu, S. Zhou, X. Liu, Y. Gao, C. Gui, and S. Liu, “Effects of GaN/AlGaN/Sputtered AlN nucleation layers on performance of GaN-based ultraviolet light-emitting diodes,” Sci. Rep. 7(1), 44627 (2017).
[Crossref] [PubMed]

S. Zhou, X. Liu, Y. Gao, Y. Liu, M. Liu, Z. Liu, C. Gui, and S. Liu, “Numerical and experimental investigation of GaN-based flip-chip light-emitting diodes with highly reflective Ag/TiW and ITO/DBR Ohmic contacts,” Opt. Express 25(22), 26615–26627 (2017).
[Crossref] [PubMed]

X. Liu, S. Zhou, Y. Gao, H. Hu, Y. Liu, C. Gui, and S. Liu, “Numerical simulation and experimental investigation of GaN-based flip-chip LEDs and top-emitting LEDs,” Appl. Opt. 56(34), 9502–9509 (2017).
[Crossref] [PubMed]

Gardner, N. F.

J. J. Wierer, D. A. Steigerwald, M. R. Krames, J. J. O’Shea, M. J. Ludowise, G. Christenson, Y.-C. Shen, C. Lowery, P. S. Martin, S. Subramanya, W. Götz, N. F. Gardner, R. S. Kern, and S. A. Stockman, “High-power AlGaInN flip-chip light-emitting diodes,” Appl. Phys. Lett. 78(22), 3379–3381 (2001).
[Crossref]

Giannakopoulos, A. E.

S. Suresh and A. E. Giannakopoulos, “A new method for estimating residual stresses by instrumented sharp indentation,” Acta Mater. 46(16), 5755–5767 (1998).
[Crossref]

Götz, W.

J. J. Wierer, D. A. Steigerwald, M. R. Krames, J. J. O’Shea, M. J. Ludowise, G. Christenson, Y.-C. Shen, C. Lowery, P. S. Martin, S. Subramanya, W. Götz, N. F. Gardner, R. S. Kern, and S. A. Stockman, “High-power AlGaInN flip-chip light-emitting diodes,” Appl. Phys. Lett. 78(22), 3379–3381 (2001).
[Crossref]

Gui, C.

Guo, X.

X. Guo and E. F. Schubert, “Current crowding and optical saturation effects in GaInN/GaN light-emitting diodes grown on insulating substrates,” Appl. Phys. Lett. 78(21), 3337–3339 (2001).
[Crossref]

Han, M.

N. Han, T. V. Cuong, M. Han, B. D. Ryu, S. Chandramohan, J. B. Park, J. H. Kang, Y. J. Park, K. B. Ko, H. Y. Kim, H. K. Kim, J. H. Ryu, Y. S. Katharria, C. J. Choi, and C. H. Hong, “Improved heat dissipation in gallium nitride light-emitting diodes with embedded graphene oxide pattern,” Nat. Commun. 4, 1452 (2013).
[Crossref] [PubMed]

Han, N.

N. Han, T. V. Cuong, M. Han, B. D. Ryu, S. Chandramohan, J. B. Park, J. H. Kang, Y. J. Park, K. B. Ko, H. Y. Kim, H. K. Kim, J. H. Ryu, Y. S. Katharria, C. J. Choi, and C. H. Hong, “Improved heat dissipation in gallium nitride light-emitting diodes with embedded graphene oxide pattern,” Nat. Commun. 4, 1452 (2013).
[Crossref] [PubMed]

Hirayama, H.

N. Maeda, J. Yun, M. Jo, and H. Hirayama, “Enhancing the light-extraction efficiency of AlGaN deep-ultraviolet light-emitting diodes using highly reflective Ni/Mg and Rh as p-type electrodes,” Jpn. J. Appl. Phys. 57(4S), 04FH08 (2018).
[Crossref]

Holcomb, M. O.

O. B. Shchekin, J. E. Epler, T. A. Trottier, T. Margalith, D. A. Steigerwald, M. O. Holcomb, P. S. Martin, and M. R. Krames, “High performance thin-film flip-chip InGaN-GaN light-emitting diodes,” Appl. Phys. Lett. 89(7), 071109 (2006).
[Crossref]

Hong, C. H.

N. Han, T. V. Cuong, M. Han, B. D. Ryu, S. Chandramohan, J. B. Park, J. H. Kang, Y. J. Park, K. B. Ko, H. Y. Kim, H. K. Kim, J. H. Ryu, Y. S. Katharria, C. J. Choi, and C. H. Hong, “Improved heat dissipation in gallium nitride light-emitting diodes with embedded graphene oxide pattern,” Nat. Commun. 4, 1452 (2013).
[Crossref] [PubMed]

Hsin, Y. M.

K. P. Hsueh, K. C. Chiang, Y. M. Hsin, and C. J. Wang, “Investigation of Cr-and Al-based metals for the reflector and Ohmic contact on n-GaN in GaN flip-chip light-emitting diodes,” Appl. Phys. Lett. 89(19), 191122 (2006).
[Crossref]

Hsueh, K. P.

K. P. Hsueh, K. C. Chiang, Y. M. Hsin, and C. J. Wang, “Investigation of Cr-and Al-based metals for the reflector and Ohmic contact on n-GaN in GaN flip-chip light-emitting diodes,” Appl. Phys. Lett. 89(19), 191122 (2006).
[Crossref]

Hu, E. L.

A. David, T. Fujii, R. Sharma, K. McGroddy, S. Nakamura, S. P. DenBaars, E. L. Hu, C. Weisbuch, and H. Benisty, “Photonic-crystal GaN light-emitting diodes with tailored guided modes distribution,” Appl. Phys. Lett. 88(6), 061124 (2006).
[Crossref]

Hu, H.

H. Hu, S. Zhou, X. Liu, Y. Gao, C. Gui, and S. Liu, “Effects of GaN/AlGaN/Sputtered AlN nucleation layers on performance of GaN-based ultraviolet light-emitting diodes,” Sci. Rep. 7(1), 44627 (2017).
[Crossref] [PubMed]

X. Liu, S. Zhou, Y. Gao, H. Hu, Y. Liu, C. Gui, and S. Liu, “Numerical simulation and experimental investigation of GaN-based flip-chip LEDs and top-emitting LEDs,” Appl. Opt. 56(34), 9502–9509 (2017).
[Crossref] [PubMed]

Hu, J.

X. Liu, N. Li, J. Hu, Y. Gao, R. Wang, and S. Zhou, “Comparative Study of Highly Reflective ITO/DBR and Ni/Ag ohmic Contacts for GaN-Based Flip-Chip Light-Emitting Diodes,” ECS J. Solid State Sci. Technol. 7(6), Q116–Q122 (2018).
[Crossref]

Huang, H. W.

C. H. Lin, C. F. Lai, T. S. Ko, H. W. Huang, H. C. Kuo, Y. Y. Hung, K. M. Leung, C. C. Yu, R. J. Tsai, C. K. Lee, T. C. Lu, and S. C. Wang, “Enhancement of InGaN–GaN Indium-Tin-Oxide Flip-Chip Light-Emitting Diodes With TiO2-SiO2 Multilayer Stack Omnidirectional Reflector,” IEEE Photonics Technol. Lett. 18(19), 2050–2052 (2006).
[Crossref]

Hung, Y. Y.

C. H. Lin, C. F. Lai, T. S. Ko, H. W. Huang, H. C. Kuo, Y. Y. Hung, K. M. Leung, C. C. Yu, R. J. Tsai, C. K. Lee, T. C. Lu, and S. C. Wang, “Enhancement of InGaN–GaN Indium-Tin-Oxide Flip-Chip Light-Emitting Diodes With TiO2-SiO2 Multilayer Stack Omnidirectional Reflector,” IEEE Photonics Technol. Lett. 18(19), 2050–2052 (2006).
[Crossref]

Hwang, S.

S. Hwang and J. Shim, “A method for current spreading analysis and electrode pattern design in light-emitting diodes,” IEEE Trans. Electron Dev. 55(5), 1123–1128 (2008).
[Crossref]

Jeon, D.-M.

J.-Y. Kim, M.-K. Kwon, I.-K. Park, C.-Y. Cho, S.-J. Park, D.-M. Jeon, J. W. Kim, and Y. C. Kim, “Enhanced light extraction efficiency in flip-chip GaN light-emitting diodes with diffuse Ag reflector on nanotextured indium-tin oxide,” Appl. Phys. Lett. 93(2), 021121 (2008).
[Crossref]

Jo, M.

N. Maeda, J. Yun, M. Jo, and H. Hirayama, “Enhancing the light-extraction efficiency of AlGaN deep-ultraviolet light-emitting diodes using highly reflective Ni/Mg and Rh as p-type electrodes,” Jpn. J. Appl. Phys. 57(4S), 04FH08 (2018).
[Crossref]

Kang, J. H.

N. Han, T. V. Cuong, M. Han, B. D. Ryu, S. Chandramohan, J. B. Park, J. H. Kang, Y. J. Park, K. B. Ko, H. Y. Kim, H. K. Kim, J. H. Ryu, Y. S. Katharria, C. J. Choi, and C. H. Hong, “Improved heat dissipation in gallium nitride light-emitting diodes with embedded graphene oxide pattern,” Nat. Commun. 4, 1452 (2013).
[Crossref] [PubMed]

Karlicek, R. F.

I. Eliashevich, Y. Li, A. Osinsky, C. A. Tran, M. G. Brown, and R. F. Karlicek, “InGaN blue light-emitting diodes with optimized n-GaN layer,” Proc. SPIE 3621, 28–36 (1999).
[Crossref]

Karpov, S. Y.

D. A. Zakheim, A. S. Pavluchenko, D. A. Bauman, K. A. Bulashevich, O. V. Khokhlev, and S. Y. Karpov, “Efficiency droop suppression in InGaN-based blue LEDs: Experiment and numerical modelling,” Phys. Status Solidi., A Appl. Mater. Sci. 209(3), 456–460 (2012).
[Crossref]

Katharria, Y. S.

N. Han, T. V. Cuong, M. Han, B. D. Ryu, S. Chandramohan, J. B. Park, J. H. Kang, Y. J. Park, K. B. Ko, H. Y. Kim, H. K. Kim, J. H. Ryu, Y. S. Katharria, C. J. Choi, and C. H. Hong, “Improved heat dissipation in gallium nitride light-emitting diodes with embedded graphene oxide pattern,” Nat. Commun. 4, 1452 (2013).
[Crossref] [PubMed]

Kern, R. S.

J. J. Wierer, D. A. Steigerwald, M. R. Krames, J. J. O’Shea, M. J. Ludowise, G. Christenson, Y.-C. Shen, C. Lowery, P. S. Martin, S. Subramanya, W. Götz, N. F. Gardner, R. S. Kern, and S. A. Stockman, “High-power AlGaInN flip-chip light-emitting diodes,” Appl. Phys. Lett. 78(22), 3379–3381 (2001).
[Crossref]

Kese, K. O.

K. O. Kese, Z. C. Li, and B. Bergman, “Influence of residual stress on elastic modulus and hardness of soda-lime glass measured by nanoindentation,” J. Mater. Res. 19(10), 3109–3119 (2004).
[Crossref]

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).
[Crossref] [PubMed]

Khokhlev, O. V.

D. A. Zakheim, A. S. Pavluchenko, D. A. Bauman, K. A. Bulashevich, O. V. Khokhlev, and S. Y. Karpov, “Efficiency droop suppression in InGaN-based blue LEDs: Experiment and numerical modelling,” Phys. Status Solidi., A Appl. Mater. Sci. 209(3), 456–460 (2012).
[Crossref]

Kim, H. K.

N. Han, T. V. Cuong, M. Han, B. D. Ryu, S. Chandramohan, J. B. Park, J. H. Kang, Y. J. Park, K. B. Ko, H. Y. Kim, H. K. Kim, J. H. Ryu, Y. S. Katharria, C. J. Choi, and C. H. Hong, “Improved heat dissipation in gallium nitride light-emitting diodes with embedded graphene oxide pattern,” Nat. Commun. 4, 1452 (2013).
[Crossref] [PubMed]

Kim, H. Y.

N. Han, T. V. Cuong, M. Han, B. D. Ryu, S. Chandramohan, J. B. Park, J. H. Kang, Y. J. Park, K. B. Ko, H. Y. Kim, H. K. Kim, J. H. Ryu, Y. S. Katharria, C. J. Choi, and C. H. Hong, “Improved heat dissipation in gallium nitride light-emitting diodes with embedded graphene oxide pattern,” Nat. Commun. 4, 1452 (2013).
[Crossref] [PubMed]

Kim, J. K.

E. F. Schubert and J. K. Kim, “Solid-state light sources getting smart,” Science 308(5726), 1274–1278 (2005).
[Crossref] [PubMed]

Kim, J. W.

J.-Y. Kim, M.-K. Kwon, I.-K. Park, C.-Y. Cho, S.-J. Park, D.-M. Jeon, J. W. Kim, and Y. C. Kim, “Enhanced light extraction efficiency in flip-chip GaN light-emitting diodes with diffuse Ag reflector on nanotextured indium-tin oxide,” Appl. Phys. Lett. 93(2), 021121 (2008).
[Crossref]

Kim, J.-Y.

J.-Y. Kim, M.-K. Kwon, I.-K. Park, C.-Y. Cho, S.-J. Park, D.-M. Jeon, J. W. Kim, and Y. C. Kim, “Enhanced light extraction efficiency in flip-chip GaN light-emitting diodes with diffuse Ag reflector on nanotextured indium-tin oxide,” Appl. Phys. Lett. 93(2), 021121 (2008).
[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]

T. H. Park, T. H. Lee, and T. G. Kim, “Al2O3/AlN/Al-based backside diffuse reflector for high-brightness 370-nm AlGaN ultraviolet light-emitting diodes,” J. Alloys Compd. 776, 1009–1015 (2019).
[Crossref]

Kim, Y. C.

J.-Y. Kim, M.-K. Kwon, I.-K. Park, C.-Y. Cho, S.-J. Park, D.-M. Jeon, J. W. Kim, and Y. C. Kim, “Enhanced light extraction efficiency in flip-chip GaN light-emitting diodes with diffuse Ag reflector on nanotextured indium-tin oxide,” Appl. Phys. Lett. 93(2), 021121 (2008).
[Crossref]

Ko, K. B.

N. Han, T. V. Cuong, M. Han, B. D. Ryu, S. Chandramohan, J. B. Park, J. H. Kang, Y. J. Park, K. B. Ko, H. Y. Kim, H. K. Kim, J. H. Ryu, Y. S. Katharria, C. J. Choi, and C. H. Hong, “Improved heat dissipation in gallium nitride light-emitting diodes with embedded graphene oxide pattern,” Nat. Commun. 4, 1452 (2013).
[Crossref] [PubMed]

Ko, T. S.

C. H. Lin, C. F. Lai, T. S. Ko, H. W. Huang, H. C. Kuo, Y. Y. Hung, K. M. Leung, C. C. Yu, R. J. Tsai, C. K. Lee, T. C. Lu, and S. C. Wang, “Enhancement of InGaN–GaN Indium-Tin-Oxide Flip-Chip Light-Emitting Diodes With TiO2-SiO2 Multilayer Stack Omnidirectional Reflector,” IEEE Photonics Technol. Lett. 18(19), 2050–2052 (2006).
[Crossref]

Krames, M. R.

O. B. Shchekin, J. E. Epler, T. A. Trottier, T. Margalith, D. A. Steigerwald, M. O. Holcomb, P. S. Martin, and M. R. Krames, “High performance thin-film flip-chip InGaN-GaN light-emitting diodes,” Appl. Phys. Lett. 89(7), 071109 (2006).
[Crossref]

J. J. Wierer, D. A. Steigerwald, M. R. Krames, J. J. O’Shea, M. J. Ludowise, G. Christenson, Y.-C. Shen, C. Lowery, P. S. Martin, S. Subramanya, W. Götz, N. F. Gardner, R. S. Kern, and S. A. Stockman, “High-power AlGaInN flip-chip light-emitting diodes,” Appl. Phys. Lett. 78(22), 3379–3381 (2001).
[Crossref]

Kuo, H. C.

C. H. Lin, C. F. Lai, T. S. Ko, H. W. Huang, H. C. Kuo, Y. Y. Hung, K. M. Leung, C. C. Yu, R. J. Tsai, C. K. Lee, T. C. Lu, and S. C. Wang, “Enhancement of InGaN–GaN Indium-Tin-Oxide Flip-Chip Light-Emitting Diodes With TiO2-SiO2 Multilayer Stack Omnidirectional Reflector,” IEEE Photonics Technol. Lett. 18(19), 2050–2052 (2006).
[Crossref]

Kwak, J. S.

J. O. Song, J. S. Kwak, Y. Park, and T. Y. Seong, “Ohmic and degradation mechanisms of Ag contacts on p-type GaN,” Appl. Phys. Lett. 86(6), 062104 (2005).
[Crossref]

Kwon, D.

Y. H. Lee and D. Kwon, “Measurement of residual-stress effect by nanoindentation on elastically strained (100) W,” Scr. Mater. 49(5), 459–465 (2003).
[Crossref]

Y. H. Lee and D. Kwon, “Residual stresses in DLC/Si and Au/Si systems: Application of a stress-relaxation model to the nanoindentation technique,” J. Mater. Res. 17, 901–906 (2002).
[Crossref]

Kwon, M.-K.

J.-Y. Kim, M.-K. Kwon, I.-K. Park, C.-Y. Cho, S.-J. Park, D.-M. Jeon, J. W. Kim, and Y. C. Kim, “Enhanced light extraction efficiency in flip-chip GaN light-emitting diodes with diffuse Ag reflector on nanotextured indium-tin oxide,” Appl. Phys. Lett. 93(2), 021121 (2008).
[Crossref]

Lai, C. F.

C. H. Lin, C. F. Lai, T. S. Ko, H. W. Huang, H. C. Kuo, Y. Y. Hung, K. M. Leung, C. C. Yu, R. J. Tsai, C. K. Lee, T. C. Lu, and S. C. Wang, “Enhancement of InGaN–GaN Indium-Tin-Oxide Flip-Chip Light-Emitting Diodes With TiO2-SiO2 Multilayer Stack Omnidirectional Reflector,” IEEE Photonics Technol. Lett. 18(19), 2050–2052 (2006).
[Crossref]

Larsson, P. L.

S. Carlsson and P. L. Larsson, “On the determination of residual stress and strain fields by sharp indentation testing: Part II. experimental investigation,” Acta Mater. 49(12), 2193–2203 (2001).
[Crossref]

S. Carlsson and P. L. Larsson, “On the determination of residual stress and strain fields by sharp indentation testing: Part I. theoretical and numerical analysis,” Acta Mater. 49(12), 2179–2191 (2001).
[Crossref]

Lau, K. M.

W. C. Chong and K. M. Lau, “Performance enhancements of flip-chip light-emitting diodes with high-density n-type point-contacts,” IEEE Electron Device Lett. 35(10), 1049–1051 (2014).
[Crossref]

Lee, C. K.

C. H. Lin, C. F. Lai, T. S. Ko, H. W. Huang, H. C. Kuo, Y. Y. Hung, K. M. Leung, C. C. Yu, R. J. Tsai, C. K. Lee, T. C. Lu, and S. C. Wang, “Enhancement of InGaN–GaN Indium-Tin-Oxide Flip-Chip Light-Emitting Diodes With TiO2-SiO2 Multilayer Stack Omnidirectional Reflector,” IEEE Photonics Technol. Lett. 18(19), 2050–2052 (2006).
[Crossref]

Lee, J. L.

J. H. Son, Y. H. Song, H. K. Yu, and J. L. Lee, “Effects of Ni cladding layers on suppression of Ag agglomeration in Ag-based Ohmic contacts on p-GaN,” Appl. Phys. Lett. 95(6), 062108 (2009).
[Crossref]

Lee, T. H.

T. H. Park, T. H. Lee, and T. G. Kim, “Al2O3/AlN/Al-based backside diffuse reflector for high-brightness 370-nm AlGaN ultraviolet light-emitting diodes,” J. Alloys Compd. 776, 1009–1015 (2019).
[Crossref]

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]

Lee, Y. H.

Y. H. Lee and D. Kwon, “Measurement of residual-stress effect by nanoindentation on elastically strained (100) W,” Scr. Mater. 49(5), 459–465 (2003).
[Crossref]

Y. H. Lee and D. Kwon, “Residual stresses in DLC/Si and Au/Si systems: Application of a stress-relaxation model to the nanoindentation technique,” J. Mater. Res. 17, 901–906 (2002).
[Crossref]

Leung, K. M.

C. H. Lin, C. F. Lai, T. S. Ko, H. W. Huang, H. C. Kuo, Y. Y. Hung, K. M. Leung, C. C. Yu, R. J. Tsai, C. K. Lee, T. C. Lu, and S. C. Wang, “Enhancement of InGaN–GaN Indium-Tin-Oxide Flip-Chip Light-Emitting Diodes With TiO2-SiO2 Multilayer Stack Omnidirectional Reflector,” IEEE Photonics Technol. Lett. 18(19), 2050–2052 (2006).
[Crossref]

Li, N.

S. Zhou, H. Xu, M. Liu, X. Liu, J. Zhao, N. Li, and S. Liu, “Effect of Dielectric Distributed Bragg Reflector on Electrical and Optical Properties of GaN-Based Flip-Chip Light-Emitting Diodes,” Micromachines (Basel) 9(12), 650 (2018).
[Crossref] [PubMed]

X. Liu, N. Li, J. Hu, Y. Gao, R. Wang, and S. Zhou, “Comparative Study of Highly Reflective ITO/DBR and Ni/Ag ohmic Contacts for GaN-Based Flip-Chip Light-Emitting Diodes,” ECS J. Solid State Sci. Technol. 7(6), Q116–Q122 (2018).
[Crossref]

Li, Y.

I. Eliashevich, Y. Li, A. Osinsky, C. A. Tran, M. G. Brown, and R. F. Karlicek, “InGaN blue light-emitting diodes with optimized n-GaN layer,” Proc. SPIE 3621, 28–36 (1999).
[Crossref]

Li, Z. C.

K. O. Kese, Z. C. Li, and B. Bergman, “Influence of residual stress on elastic modulus and hardness of soda-lime glass measured by nanoindentation,” J. Mater. Res. 19(10), 3109–3119 (2004).
[Crossref]

Lin, C. H.

C. H. Lin, C. F. Lai, T. S. Ko, H. W. Huang, H. C. Kuo, Y. Y. Hung, K. M. Leung, C. C. Yu, R. J. Tsai, C. K. Lee, T. C. Lu, and S. C. Wang, “Enhancement of InGaN–GaN Indium-Tin-Oxide Flip-Chip Light-Emitting Diodes With TiO2-SiO2 Multilayer Stack Omnidirectional Reflector,” IEEE Photonics Technol. Lett. 18(19), 2050–2052 (2006).
[Crossref]

Liu, G.

H. Zhao, G. Liu, R. A. Arif, and 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, M.

S. Zhou, H. Xu, M. Liu, X. Liu, J. Zhao, N. Li, and S. Liu, “Effect of Dielectric Distributed Bragg Reflector on Electrical and Optical Properties of GaN-Based Flip-Chip Light-Emitting Diodes,” Micromachines (Basel) 9(12), 650 (2018).
[Crossref] [PubMed]

S. Zhou, X. Liu, Y. Gao, Y. Liu, M. Liu, Z. Liu, C. Gui, and S. Liu, “Numerical and experimental investigation of GaN-based flip-chip light-emitting diodes with highly reflective Ag/TiW and ITO/DBR Ohmic contacts,” Opt. Express 25(22), 26615–26627 (2017).
[Crossref] [PubMed]

Liu, S.

S. Zhou, H. Xu, M. Liu, X. Liu, J. Zhao, N. Li, and S. Liu, “Effect of Dielectric Distributed Bragg Reflector on Electrical and Optical Properties of GaN-Based Flip-Chip Light-Emitting Diodes,” Micromachines (Basel) 9(12), 650 (2018).
[Crossref] [PubMed]

H. Hu, S. Zhou, X. Liu, Y. Gao, C. Gui, and S. Liu, “Effects of GaN/AlGaN/Sputtered AlN nucleation layers on performance of GaN-based ultraviolet light-emitting diodes,” Sci. Rep. 7(1), 44627 (2017).
[Crossref] [PubMed]

S. Zhou, X. Liu, Y. Gao, Y. Liu, M. Liu, Z. Liu, C. Gui, and S. Liu, “Numerical and experimental investigation of GaN-based flip-chip light-emitting diodes with highly reflective Ag/TiW and ITO/DBR Ohmic contacts,” Opt. Express 25(22), 26615–26627 (2017).
[Crossref] [PubMed]

X. Liu, S. Zhou, Y. Gao, H. Hu, Y. Liu, C. Gui, and S. Liu, “Numerical simulation and experimental investigation of GaN-based flip-chip LEDs and top-emitting LEDs,” Appl. Opt. 56(34), 9502–9509 (2017).
[Crossref] [PubMed]

J. Lv, C. Zheng, Q. Chen, S. Zhou, and S. Liu, “High power InGaN/GaN flip-chip LEDs with via-hole-based two-level metallization electrodes,” Phys. Status Solidi., A Appl. Mater. Sci. 213(12), 3150–3156 (2016).
[Crossref]

Liu, X.

S. Zhou, H. Xu, M. Liu, X. Liu, J. Zhao, N. Li, and S. Liu, “Effect of Dielectric Distributed Bragg Reflector on Electrical and Optical Properties of GaN-Based Flip-Chip Light-Emitting Diodes,” Micromachines (Basel) 9(12), 650 (2018).
[Crossref] [PubMed]

X. Liu, N. Li, J. Hu, Y. Gao, R. Wang, and S. Zhou, “Comparative Study of Highly Reflective ITO/DBR and Ni/Ag ohmic Contacts for GaN-Based Flip-Chip Light-Emitting Diodes,” ECS J. Solid State Sci. Technol. 7(6), Q116–Q122 (2018).
[Crossref]

H. Hu, S. Zhou, X. Liu, Y. Gao, C. Gui, and S. Liu, “Effects of GaN/AlGaN/Sputtered AlN nucleation layers on performance of GaN-based ultraviolet light-emitting diodes,” Sci. Rep. 7(1), 44627 (2017).
[Crossref] [PubMed]

S. Zhou, X. Liu, Y. Gao, Y. Liu, M. Liu, Z. Liu, C. Gui, and S. Liu, “Numerical and experimental investigation of GaN-based flip-chip light-emitting diodes with highly reflective Ag/TiW and ITO/DBR Ohmic contacts,” Opt. Express 25(22), 26615–26627 (2017).
[Crossref] [PubMed]

X. Liu, S. Zhou, Y. Gao, H. Hu, Y. Liu, C. Gui, and S. Liu, “Numerical simulation and experimental investigation of GaN-based flip-chip LEDs and top-emitting LEDs,” Appl. Opt. 56(34), 9502–9509 (2017).
[Crossref] [PubMed]

Liu, Y.

Liu, Z.

Lowery, C.

J. J. Wierer, D. A. Steigerwald, M. R. Krames, J. J. O’Shea, M. J. Ludowise, G. Christenson, Y.-C. Shen, C. Lowery, P. S. Martin, S. Subramanya, W. Götz, N. F. Gardner, R. S. Kern, and S. A. Stockman, “High-power AlGaInN flip-chip light-emitting diodes,” Appl. Phys. Lett. 78(22), 3379–3381 (2001).
[Crossref]

Lu, T. C.

C. H. Lin, C. F. Lai, T. S. Ko, H. W. Huang, H. C. Kuo, Y. Y. Hung, K. M. Leung, C. C. Yu, R. J. Tsai, C. K. Lee, T. C. Lu, and S. C. Wang, “Enhancement of InGaN–GaN Indium-Tin-Oxide Flip-Chip Light-Emitting Diodes With TiO2-SiO2 Multilayer Stack Omnidirectional Reflector,” IEEE Photonics Technol. Lett. 18(19), 2050–2052 (2006).
[Crossref]

Ludowise, M. J.

J. J. Wierer, D. A. Steigerwald, M. R. Krames, J. J. O’Shea, M. J. Ludowise, G. Christenson, Y.-C. Shen, C. Lowery, P. S. Martin, S. Subramanya, W. Götz, N. F. Gardner, R. S. Kern, and S. A. Stockman, “High-power AlGaInN flip-chip light-emitting diodes,” Appl. Phys. Lett. 78(22), 3379–3381 (2001).
[Crossref]

Lv, J.

J. Lv, C. Zheng, Q. Chen, S. Zhou, and S. Liu, “High power InGaN/GaN flip-chip LEDs with via-hole-based two-level metallization electrodes,” Phys. Status Solidi., A Appl. Mater. Sci. 213(12), 3150–3156 (2016).
[Crossref]

Maeda, N.

N. Maeda, J. Yun, M. Jo, and H. Hirayama, “Enhancing the light-extraction efficiency of AlGaN deep-ultraviolet light-emitting diodes using highly reflective Ni/Mg and Rh as p-type electrodes,” Jpn. J. Appl. Phys. 57(4S), 04FH08 (2018).
[Crossref]

Margalith, T.

O. B. Shchekin, J. E. Epler, T. A. Trottier, T. Margalith, D. A. Steigerwald, M. O. Holcomb, P. S. Martin, and M. R. Krames, “High performance thin-film flip-chip InGaN-GaN light-emitting diodes,” Appl. Phys. Lett. 89(7), 071109 (2006).
[Crossref]

Martin, P. S.

O. B. Shchekin, J. E. Epler, T. A. Trottier, T. Margalith, D. A. Steigerwald, M. O. Holcomb, P. S. Martin, and M. R. Krames, “High performance thin-film flip-chip InGaN-GaN light-emitting diodes,” Appl. Phys. Lett. 89(7), 071109 (2006).
[Crossref]

J. J. Wierer, D. A. Steigerwald, M. R. Krames, J. J. O’Shea, M. J. Ludowise, G. Christenson, Y.-C. Shen, C. Lowery, P. S. Martin, S. Subramanya, W. Götz, N. F. Gardner, R. S. Kern, and S. A. Stockman, “High-power AlGaInN flip-chip light-emitting diodes,” Appl. Phys. Lett. 78(22), 3379–3381 (2001).
[Crossref]

McGroddy, K.

A. David, T. Fujii, R. Sharma, K. McGroddy, S. Nakamura, S. P. DenBaars, E. L. Hu, C. Weisbuch, and H. Benisty, “Photonic-crystal GaN light-emitting diodes with tailored guided modes distribution,” Appl. Phys. Lett. 88(6), 061124 (2006).
[Crossref]

Megens, M. M.

J. J. Wierer, A. David, and M. M. Megens, “III-nitride photonic-crystal light-emitting diodes with high extraction efficiency,” Nat. Photonics 3(3), 163–169 (2009).
[Crossref]

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]

Nakamura, S.

B. P. Yonkee, E. C. Young, S. P. DenBaars, S. Nakamura, and J. S. Speck, “Silver free III-nitride flip chip light emitting-diode with wall plug efficiency over 70% utilizing a GaN tunnel junction,” Appl. Phys. Lett. 109(19), 191104 (2016).
[Crossref] [PubMed]

S. Pimputkar, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Prospects for LED lighting,” Nat. Photonics 3(4), 180–182 (2009).
[Crossref]

A. David, T. Fujii, R. Sharma, K. McGroddy, S. Nakamura, S. P. DenBaars, E. L. Hu, C. Weisbuch, and H. Benisty, “Photonic-crystal GaN light-emitting diodes with tailored guided modes distribution,” Appl. Phys. Lett. 88(6), 061124 (2006).
[Crossref]

O’Shea, J. J.

J. J. Wierer, D. A. Steigerwald, M. R. Krames, J. J. O’Shea, M. J. Ludowise, G. Christenson, Y.-C. Shen, C. Lowery, P. S. Martin, S. Subramanya, W. Götz, N. F. Gardner, R. S. Kern, and S. A. Stockman, “High-power AlGaInN flip-chip light-emitting diodes,” Appl. Phys. Lett. 78(22), 3379–3381 (2001).
[Crossref]

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]

Oliver, W. C.

T. Y. Tsui, W. C. Oliver, and G. M. Pharr, “Influences of stress on the measurement of mechanical properties using nanoindentation: Part I. Experimental studies in an aluminum alloy,” J. Mater. Res. 11, 752–759 (1996).
[Crossref]

T. Y. Tsui, W. C. Oliver, and G. M. Pharr, “Influences of stress on the measurement of mechanical properties using nanoindentation: Part I. Experimental studies in an aluminum alloy,” J. Mater. Res. 11(03), 752–759 (1996).
[Crossref]

A. Bolshakov, W. C. Oliver, and G. M. Pharr, “Influences of stress on the measurement of mechanical properties using nanoindentation: Part II. Finite element simulations,” J. Mater. Res. 11(03), 760–768 (1996).
[Crossref]

Osinsky, A.

I. Eliashevich, Y. Li, A. Osinsky, C. A. Tran, M. G. Brown, and R. F. Karlicek, “InGaN blue light-emitting diodes with optimized n-GaN layer,” Proc. SPIE 3621, 28–36 (1999).
[Crossref]

Park, I.-K.

J.-Y. Kim, M.-K. Kwon, I.-K. Park, C.-Y. Cho, S.-J. Park, D.-M. Jeon, J. W. Kim, and Y. C. Kim, “Enhanced light extraction efficiency in flip-chip GaN light-emitting diodes with diffuse Ag reflector on nanotextured indium-tin oxide,” Appl. Phys. Lett. 93(2), 021121 (2008).
[Crossref]

Park, J. B.

N. Han, T. V. Cuong, M. Han, B. D. Ryu, S. Chandramohan, J. B. Park, J. H. Kang, Y. J. Park, K. B. Ko, H. Y. Kim, H. K. Kim, J. H. Ryu, Y. S. Katharria, C. J. Choi, and C. H. Hong, “Improved heat dissipation in gallium nitride light-emitting diodes with embedded graphene oxide pattern,” Nat. Commun. 4, 1452 (2013).
[Crossref] [PubMed]

Park, S.-J.

J.-Y. Kim, M.-K. Kwon, I.-K. Park, C.-Y. Cho, S.-J. Park, D.-M. Jeon, J. W. Kim, and Y. C. Kim, “Enhanced light extraction efficiency in flip-chip GaN light-emitting diodes with diffuse Ag reflector on nanotextured indium-tin oxide,” Appl. Phys. Lett. 93(2), 021121 (2008).
[Crossref]

Park, T. H.

T. H. Park, T. H. Lee, and T. G. Kim, “Al2O3/AlN/Al-based backside diffuse reflector for high-brightness 370-nm AlGaN ultraviolet light-emitting diodes,” J. Alloys Compd. 776, 1009–1015 (2019).
[Crossref]

Park, Y.

J. O. Song, J. S. Kwak, Y. Park, and T. Y. Seong, “Ohmic and degradation mechanisms of Ag contacts on p-type GaN,” Appl. Phys. Lett. 86(6), 062104 (2005).
[Crossref]

Park, Y. J.

N. Han, T. V. Cuong, M. Han, B. D. Ryu, S. Chandramohan, J. B. Park, J. H. Kang, Y. J. Park, K. B. Ko, H. Y. Kim, H. K. Kim, J. H. Ryu, Y. S. Katharria, C. J. Choi, and C. H. Hong, “Improved heat dissipation in gallium nitride light-emitting diodes with embedded graphene oxide pattern,” Nat. Commun. 4, 1452 (2013).
[Crossref] [PubMed]

Pavluchenko, A. S.

D. A. Zakheim, A. S. Pavluchenko, D. A. Bauman, K. A. Bulashevich, O. V. Khokhlev, and S. Y. Karpov, “Efficiency droop suppression in InGaN-based blue LEDs: Experiment and numerical modelling,” Phys. Status Solidi., A Appl. Mater. Sci. 209(3), 456–460 (2012).
[Crossref]

Perdew, J. P.

J. P. Perdew, K. Burke, and M. Ernzerhof, “Generalized gradient approximation made simple,” Phys. Rev. Lett. 77(18), 3865–3868 (1996).
[Crossref] [PubMed]

Pharr, G. M.

T. Y. Tsui, W. C. Oliver, and G. M. Pharr, “Influences of stress on the measurement of mechanical properties using nanoindentation: Part I. Experimental studies in an aluminum alloy,” J. Mater. Res. 11, 752–759 (1996).
[Crossref]

A. Bolshakov, W. C. Oliver, and G. M. Pharr, “Influences of stress on the measurement of mechanical properties using nanoindentation: Part II. Finite element simulations,” J. Mater. Res. 11(03), 760–768 (1996).
[Crossref]

T. Y. Tsui, W. C. Oliver, and G. M. Pharr, “Influences of stress on the measurement of mechanical properties using nanoindentation: Part I. Experimental studies in an aluminum alloy,” J. Mater. Res. 11(03), 752–759 (1996).
[Crossref]

Pimputkar, S.

S. Pimputkar, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Prospects for LED lighting,” Nat. Photonics 3(4), 180–182 (2009).
[Crossref]

Ponce, F. A.

F. A. Ponce and D. P. Bour, “Nitride-based semiconductors for blue and green light-emitting devices,” Nature 386(6623), 351–359 (1997).
[Crossref]

Qu, J.

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]

Resta, R.

A. Baldereschi, S. Baroni, and R. Resta, “Band Offsets in Lattice-Matched Heterojunctions: A Model and First-Principles Calculations for GaAs/AlAs,” Phys. Rev. Lett. 61(6), 734–737 (1988).
[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).
[Crossref] [PubMed]

Ryu, B. D.

N. Han, T. V. Cuong, M. Han, B. D. Ryu, S. Chandramohan, J. B. Park, J. H. Kang, Y. J. Park, K. B. Ko, H. Y. Kim, H. K. Kim, J. H. Ryu, Y. S. Katharria, C. J. Choi, and C. H. Hong, “Improved heat dissipation in gallium nitride light-emitting diodes with embedded graphene oxide pattern,” Nat. Commun. 4, 1452 (2013).
[Crossref] [PubMed]

Ryu, H. Y.

Ryu, J. H.

N. Han, T. V. Cuong, M. Han, B. D. Ryu, S. Chandramohan, J. B. Park, J. H. Kang, Y. J. Park, K. B. Ko, H. Y. Kim, H. K. Kim, J. H. Ryu, Y. S. Katharria, C. J. Choi, and C. H. Hong, “Improved heat dissipation in gallium nitride light-emitting diodes with embedded graphene oxide pattern,” Nat. Commun. 4, 1452 (2013).
[Crossref] [PubMed]

Schubert, E. F.

E. F. Schubert and J. K. Kim, “Solid-state light sources getting smart,” Science 308(5726), 1274–1278 (2005).
[Crossref] [PubMed]

X. Guo and E. F. Schubert, “Current crowding and optical saturation effects in GaInN/GaN light-emitting diodes grown on insulating substrates,” Appl. Phys. Lett. 78(21), 3337–3339 (2001).
[Crossref]

Seong, T. Y.

J. O. Song, J. S. Kwak, Y. Park, and T. Y. Seong, “Ohmic and degradation mechanisms of Ag contacts on p-type GaN,” Appl. Phys. Lett. 86(6), 062104 (2005).
[Crossref]

Sharma, R.

A. David, T. Fujii, R. Sharma, K. McGroddy, S. Nakamura, S. P. DenBaars, E. L. Hu, C. Weisbuch, and H. Benisty, “Photonic-crystal GaN light-emitting diodes with tailored guided modes distribution,” Appl. Phys. Lett. 88(6), 061124 (2006).
[Crossref]

Shatalov, M.

M. Shatalov and A. Chitnisl, “Thermal analysis of flip-chip packaged 280 nm nitride-based deep ultraviolet light-emitting diodes,” Appl. Phys. Lett. 86(20), 2201109 (2016).

Shchekin, O. B.

O. B. Shchekin, J. E. Epler, T. A. Trottier, T. Margalith, D. A. Steigerwald, M. O. Holcomb, P. S. Martin, and M. R. Krames, “High performance thin-film flip-chip InGaN-GaN light-emitting diodes,” Appl. Phys. Lett. 89(7), 071109 (2006).
[Crossref]

Shen, Y.-C.

J. J. Wierer, D. A. Steigerwald, M. R. Krames, J. J. O’Shea, M. J. Ludowise, G. Christenson, Y.-C. Shen, C. Lowery, P. S. Martin, S. Subramanya, W. Götz, N. F. Gardner, R. S. Kern, and S. A. Stockman, “High-power AlGaInN flip-chip light-emitting diodes,” Appl. Phys. Lett. 78(22), 3379–3381 (2001).
[Crossref]

Sheu, J. K.

J. K. Sheu and G. C. Chi, “The doping process and dopant characteristics of GaN,” J. Phys. Condens. Matter 14(22), R657 (2002).
[Crossref]

Shim, J.

S. Hwang and J. Shim, “A method for current spreading analysis and electrode pattern design in light-emitting diodes,” IEEE Trans. Electron Dev. 55(5), 1123–1128 (2008).
[Crossref]

Shim, J. I.

Son, J. H.

J. H. Son, Y. H. Song, H. K. Yu, and J. L. Lee, “Effects of Ni cladding layers on suppression of Ag agglomeration in Ag-based Ohmic contacts on p-GaN,” Appl. Phys. Lett. 95(6), 062108 (2009).
[Crossref]

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.

J. O. Song, J. S. Kwak, Y. Park, and T. Y. Seong, “Ohmic and degradation mechanisms of Ag contacts on p-type GaN,” Appl. Phys. Lett. 86(6), 062104 (2005).
[Crossref]

Song, Y. H.

J. H. Son, Y. H. Song, H. K. Yu, and J. L. Lee, “Effects of Ni cladding layers on suppression of Ag agglomeration in Ag-based Ohmic contacts on p-GaN,” Appl. Phys. Lett. 95(6), 062108 (2009).
[Crossref]

Spaldin, N. A.

K. T. Delaney, N. A. Spaldin, and C. G. Van de Walle, “Theoretical study of Schottky-barrier formation at epitaxial rare-earth-metal/semiconductor interfaces,” Phys. Rev. B Condens. Matter Mater. Phys. 81(16), 165312 (2010).
[Crossref]

Speck, J. S.

B. P. Yonkee, E. C. Young, S. P. DenBaars, S. Nakamura, and J. S. Speck, “Silver free III-nitride flip chip light emitting-diode with wall plug efficiency over 70% utilizing a GaN tunnel junction,” Appl. Phys. Lett. 109(19), 191104 (2016).
[Crossref] [PubMed]

S. Pimputkar, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Prospects for LED lighting,” Nat. Photonics 3(4), 180–182 (2009).
[Crossref]

Steigerwald, D. A.

O. B. Shchekin, J. E. Epler, T. A. Trottier, T. Margalith, D. A. Steigerwald, M. O. Holcomb, P. S. Martin, and M. R. Krames, “High performance thin-film flip-chip InGaN-GaN light-emitting diodes,” Appl. Phys. Lett. 89(7), 071109 (2006).
[Crossref]

J. J. Wierer, D. A. Steigerwald, M. R. Krames, J. J. O’Shea, M. J. Ludowise, G. Christenson, Y.-C. Shen, C. Lowery, P. S. Martin, S. Subramanya, W. Götz, N. F. Gardner, R. S. Kern, and S. A. Stockman, “High-power AlGaInN flip-chip light-emitting diodes,” Appl. Phys. Lett. 78(22), 3379–3381 (2001).
[Crossref]

Stockman, S. A.

J. J. Wierer, D. A. Steigerwald, M. R. Krames, J. J. O’Shea, M. J. Ludowise, G. Christenson, Y.-C. Shen, C. Lowery, P. S. Martin, S. Subramanya, W. Götz, N. F. Gardner, R. S. Kern, and S. A. Stockman, “High-power AlGaInN flip-chip light-emitting diodes,” Appl. Phys. Lett. 78(22), 3379–3381 (2001).
[Crossref]

Subramanya, S.

J. J. Wierer, D. A. Steigerwald, M. R. Krames, J. J. O’Shea, M. J. Ludowise, G. Christenson, Y.-C. Shen, C. Lowery, P. S. Martin, S. Subramanya, W. Götz, N. F. Gardner, R. S. Kern, and S. A. Stockman, “High-power AlGaInN flip-chip light-emitting diodes,” Appl. Phys. Lett. 78(22), 3379–3381 (2001).
[Crossref]

Suresh, S.

S. Suresh and A. E. Giannakopoulos, “A new method for estimating residual stresses by instrumented sharp indentation,” Acta Mater. 46(16), 5755–5767 (1998).
[Crossref]

Tansu, N.

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

Tran, C. A.

I. Eliashevich, Y. Li, A. Osinsky, C. A. Tran, M. G. Brown, and R. F. Karlicek, “InGaN blue light-emitting diodes with optimized n-GaN layer,” Proc. SPIE 3621, 28–36 (1999).
[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]

Trottier, T. A.

O. B. Shchekin, J. E. Epler, T. A. Trottier, T. Margalith, D. A. Steigerwald, M. O. Holcomb, P. S. Martin, and M. R. Krames, “High performance thin-film flip-chip InGaN-GaN light-emitting diodes,” Appl. Phys. Lett. 89(7), 071109 (2006).
[Crossref]

Tsai, R. J.

C. H. Lin, C. F. Lai, T. S. Ko, H. W. Huang, H. C. Kuo, Y. Y. Hung, K. M. Leung, C. C. Yu, R. J. Tsai, C. K. Lee, T. C. Lu, and S. C. Wang, “Enhancement of InGaN–GaN Indium-Tin-Oxide Flip-Chip Light-Emitting Diodes With TiO2-SiO2 Multilayer Stack Omnidirectional Reflector,” IEEE Photonics Technol. Lett. 18(19), 2050–2052 (2006).
[Crossref]

Tsui, T. Y.

T. Y. Tsui, W. C. Oliver, and G. M. Pharr, “Influences of stress on the measurement of mechanical properties using nanoindentation: Part I. Experimental studies in an aluminum alloy,” J. Mater. Res. 11, 752–759 (1996).
[Crossref]

T. Y. Tsui, W. C. Oliver, and G. M. Pharr, “Influences of stress on the measurement of mechanical properties using nanoindentation: Part I. Experimental studies in an aluminum alloy,” J. Mater. Res. 11(03), 752–759 (1996).
[Crossref]

Tung, R. T.

R. T. Tung, “The physics and chemistry of the Schottky barrier height,” Appl. Phys. Lett. 1(1), 011304 (2014).

Van de Walle, C. G.

K. T. Delaney, N. A. Spaldin, and C. G. Van de Walle, “Theoretical study of Schottky-barrier formation at epitaxial rare-earth-metal/semiconductor interfaces,” Phys. Rev. B Condens. Matter Mater. Phys. 81(16), 165312 (2010).
[Crossref]

Wang, C. B.

L. N. Zhu, B. S. Xu, H. D. Wang, and C. B. Wang, “Measurement of residual stress in quenched 1045 steel by the nanoindentation method,” Mater. Charact. 61(12), 1359–1362 (2010).
[Crossref]

Wang, C. J.

K. P. Hsueh, K. C. Chiang, Y. M. Hsin, and C. J. Wang, “Investigation of Cr-and Al-based metals for the reflector and Ohmic contact on n-GaN in GaN flip-chip light-emitting diodes,” Appl. Phys. Lett. 89(19), 191122 (2006).
[Crossref]

Wang, H. D.

L. N. Zhu, B. S. Xu, H. D. Wang, and C. B. Wang, “Measurement of residual stress in quenched 1045 steel by the nanoindentation method,” Mater. Charact. 61(12), 1359–1362 (2010).
[Crossref]

Wang, R.

X. Liu, N. Li, J. Hu, Y. Gao, R. Wang, and S. Zhou, “Comparative Study of Highly Reflective ITO/DBR and Ni/Ag ohmic Contacts for GaN-Based Flip-Chip Light-Emitting Diodes,” ECS J. Solid State Sci. Technol. 7(6), Q116–Q122 (2018).
[Crossref]

Wang, S. C.

C. H. Lin, C. F. Lai, T. S. Ko, H. W. Huang, H. C. Kuo, Y. Y. Hung, K. M. Leung, C. C. Yu, R. J. Tsai, C. K. Lee, T. C. Lu, and S. C. Wang, “Enhancement of InGaN–GaN Indium-Tin-Oxide Flip-Chip Light-Emitting Diodes With TiO2-SiO2 Multilayer Stack Omnidirectional Reflector,” IEEE Photonics Technol. Lett. 18(19), 2050–2052 (2006).
[Crossref]

Weisbuch, C.

A. David, T. Fujii, R. Sharma, K. McGroddy, S. Nakamura, S. P. DenBaars, E. L. Hu, C. Weisbuch, and H. Benisty, “Photonic-crystal GaN light-emitting diodes with tailored guided modes distribution,” Appl. Phys. Lett. 88(6), 061124 (2006).
[Crossref]

Wierer, J. J.

J. J. Wierer, A. David, and M. M. Megens, “III-nitride photonic-crystal light-emitting diodes with high extraction efficiency,” Nat. Photonics 3(3), 163–169 (2009).
[Crossref]

J. J. Wierer, D. A. Steigerwald, M. R. Krames, J. J. O’Shea, M. J. Ludowise, G. Christenson, Y.-C. Shen, C. Lowery, P. S. Martin, S. Subramanya, W. Götz, N. F. Gardner, R. S. Kern, and S. A. Stockman, “High-power AlGaInN flip-chip light-emitting diodes,” Appl. Phys. Lett. 78(22), 3379–3381 (2001).
[Crossref]

Xu, B. S.

L. N. Zhu, B. S. Xu, H. D. Wang, and C. B. Wang, “Measurement of residual stress in quenched 1045 steel by the nanoindentation method,” Mater. Charact. 61(12), 1359–1362 (2010).
[Crossref]

Xu, H.

S. Zhou, H. Xu, M. Liu, X. Liu, J. Zhao, N. Li, and S. Liu, “Effect of Dielectric Distributed Bragg Reflector on Electrical and Optical Properties of GaN-Based Flip-Chip Light-Emitting Diodes,” Micromachines (Basel) 9(12), 650 (2018).
[Crossref] [PubMed]

Yao, Y.

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]

Yonkee, B. P.

B. P. Yonkee, E. C. Young, S. P. DenBaars, S. Nakamura, and J. S. Speck, “Silver free III-nitride flip chip light emitting-diode with wall plug efficiency over 70% utilizing a GaN tunnel junction,” Appl. Phys. Lett. 109(19), 191104 (2016).
[Crossref] [PubMed]

Young, E. C.

B. P. Yonkee, E. C. Young, S. P. DenBaars, S. Nakamura, and J. S. Speck, “Silver free III-nitride flip chip light emitting-diode with wall plug efficiency over 70% utilizing a GaN tunnel junction,” Appl. Phys. Lett. 109(19), 191104 (2016).
[Crossref] [PubMed]

Yu, C. C.

C. H. Lin, C. F. Lai, T. S. Ko, H. W. Huang, H. C. Kuo, Y. Y. Hung, K. M. Leung, C. C. Yu, R. J. Tsai, C. K. Lee, T. C. Lu, and S. C. Wang, “Enhancement of InGaN–GaN Indium-Tin-Oxide Flip-Chip Light-Emitting Diodes With TiO2-SiO2 Multilayer Stack Omnidirectional Reflector,” IEEE Photonics Technol. Lett. 18(19), 2050–2052 (2006).
[Crossref]

Yu, H. K.

J. H. Son, Y. H. Song, H. K. Yu, and J. L. Lee, “Effects of Ni cladding layers on suppression of Ag agglomeration in Ag-based Ohmic contacts on p-GaN,” Appl. Phys. Lett. 95(6), 062108 (2009).
[Crossref]

Yun, J.

N. Maeda, J. Yun, M. Jo, and H. Hirayama, “Enhancing the light-extraction efficiency of AlGaN deep-ultraviolet light-emitting diodes using highly reflective Ni/Mg and Rh as p-type electrodes,” Jpn. J. Appl. Phys. 57(4S), 04FH08 (2018).
[Crossref]

Zakheim, D. A.

D. A. Zakheim, A. S. Pavluchenko, D. A. Bauman, K. A. Bulashevich, O. V. Khokhlev, and S. Y. Karpov, “Efficiency droop suppression in InGaN-based blue LEDs: Experiment and numerical modelling,” Phys. Status Solidi., A Appl. Mater. Sci. 209(3), 456–460 (2012).
[Crossref]

Zhao, H.

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

Zhao, J.

S. Zhou, H. Xu, M. Liu, X. Liu, J. Zhao, N. Li, and S. Liu, “Effect of Dielectric Distributed Bragg Reflector on Electrical and Optical Properties of GaN-Based Flip-Chip Light-Emitting Diodes,” Micromachines (Basel) 9(12), 650 (2018).
[Crossref] [PubMed]

Zheng, C.

J. Lv, C. Zheng, Q. Chen, S. Zhou, and S. Liu, “High power InGaN/GaN flip-chip LEDs with via-hole-based two-level metallization electrodes,” Phys. Status Solidi., A Appl. Mater. Sci. 213(12), 3150–3156 (2016).
[Crossref]

Zheng, R.

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]

Zhou, S.

S. Zhou, H. Xu, M. Liu, X. Liu, J. Zhao, N. Li, and S. Liu, “Effect of Dielectric Distributed Bragg Reflector on Electrical and Optical Properties of GaN-Based Flip-Chip Light-Emitting Diodes,” Micromachines (Basel) 9(12), 650 (2018).
[Crossref] [PubMed]

X. Liu, N. Li, J. Hu, Y. Gao, R. Wang, and S. Zhou, “Comparative Study of Highly Reflective ITO/DBR and Ni/Ag ohmic Contacts for GaN-Based Flip-Chip Light-Emitting Diodes,” ECS J. Solid State Sci. Technol. 7(6), Q116–Q122 (2018).
[Crossref]

H. Hu, S. Zhou, X. Liu, Y. Gao, C. Gui, and S. Liu, “Effects of GaN/AlGaN/Sputtered AlN nucleation layers on performance of GaN-based ultraviolet light-emitting diodes,” Sci. Rep. 7(1), 44627 (2017).
[Crossref] [PubMed]

S. Zhou, X. Liu, Y. Gao, Y. Liu, M. Liu, Z. Liu, C. Gui, and S. Liu, “Numerical and experimental investigation of GaN-based flip-chip light-emitting diodes with highly reflective Ag/TiW and ITO/DBR Ohmic contacts,” Opt. Express 25(22), 26615–26627 (2017).
[Crossref] [PubMed]

X. Liu, S. Zhou, Y. Gao, H. Hu, Y. Liu, C. Gui, and S. Liu, “Numerical simulation and experimental investigation of GaN-based flip-chip LEDs and top-emitting LEDs,” Appl. Opt. 56(34), 9502–9509 (2017).
[Crossref] [PubMed]

J. Lv, C. Zheng, Q. Chen, S. Zhou, and S. Liu, “High power InGaN/GaN flip-chip LEDs with via-hole-based two-level metallization electrodes,” Phys. Status Solidi., A Appl. Mater. Sci. 213(12), 3150–3156 (2016).
[Crossref]

Zhu, L. N.

L. N. Zhu, B. S. Xu, H. D. Wang, and C. B. Wang, “Measurement of residual stress in quenched 1045 steel by the nanoindentation method,” Mater. Charact. 61(12), 1359–1362 (2010).
[Crossref]

ACS Appl. Mater. Interfaces (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]

Acta Mater. (3)

S. Suresh and A. E. Giannakopoulos, “A new method for estimating residual stresses by instrumented sharp indentation,” Acta Mater. 46(16), 5755–5767 (1998).
[Crossref]

S. Carlsson and P. L. Larsson, “On the determination of residual stress and strain fields by sharp indentation testing: Part I. theoretical and numerical analysis,” Acta Mater. 49(12), 2179–2191 (2001).
[Crossref]

S. Carlsson and P. L. Larsson, “On the determination of residual stress and strain fields by sharp indentation testing: Part II. experimental investigation,” Acta Mater. 49(12), 2193–2203 (2001).
[Crossref]

Appl. Opt. (1)

Appl. Phys. Lett. (11)

K. P. Hsueh, K. C. Chiang, Y. M. Hsin, and C. J. Wang, “Investigation of Cr-and Al-based metals for the reflector and Ohmic contact on n-GaN in GaN flip-chip light-emitting diodes,” Appl. Phys. Lett. 89(19), 191122 (2006).
[Crossref]

J.-Y. Kim, M.-K. Kwon, I.-K. Park, C.-Y. Cho, S.-J. Park, D.-M. Jeon, J. W. Kim, and Y. C. Kim, “Enhanced light extraction efficiency in flip-chip GaN light-emitting diodes with diffuse Ag reflector on nanotextured indium-tin oxide,” Appl. Phys. Lett. 93(2), 021121 (2008).
[Crossref]

A. David, T. Fujii, R. Sharma, K. McGroddy, S. Nakamura, S. P. DenBaars, E. L. Hu, C. Weisbuch, and H. Benisty, “Photonic-crystal GaN light-emitting diodes with tailored guided modes distribution,” Appl. Phys. Lett. 88(6), 061124 (2006).
[Crossref]

J. J. Wierer, D. A. Steigerwald, M. R. Krames, J. J. O’Shea, M. J. Ludowise, G. Christenson, Y.-C. Shen, C. Lowery, P. S. Martin, S. Subramanya, W. Götz, N. F. Gardner, R. S. Kern, and S. A. Stockman, “High-power AlGaInN flip-chip light-emitting diodes,” Appl. Phys. Lett. 78(22), 3379–3381 (2001).
[Crossref]

B. P. Yonkee, E. C. Young, S. P. DenBaars, S. Nakamura, and J. S. Speck, “Silver free III-nitride flip chip light emitting-diode with wall plug efficiency over 70% utilizing a GaN tunnel junction,” Appl. Phys. Lett. 109(19), 191104 (2016).
[Crossref] [PubMed]

O. B. Shchekin, J. E. Epler, T. A. Trottier, T. Margalith, D. A. Steigerwald, M. O. Holcomb, P. S. Martin, and M. R. Krames, “High performance thin-film flip-chip InGaN-GaN light-emitting diodes,” Appl. Phys. Lett. 89(7), 071109 (2006).
[Crossref]

M. Shatalov and A. Chitnisl, “Thermal analysis of flip-chip packaged 280 nm nitride-based deep ultraviolet light-emitting diodes,” Appl. Phys. Lett. 86(20), 2201109 (2016).

R. T. Tung, “The physics and chemistry of the Schottky barrier height,” Appl. Phys. Lett. 1(1), 011304 (2014).

J. O. Song, J. S. Kwak, Y. Park, and T. Y. Seong, “Ohmic and degradation mechanisms of Ag contacts on p-type GaN,” Appl. Phys. Lett. 86(6), 062104 (2005).
[Crossref]

J. H. Son, Y. H. Song, H. K. Yu, and J. L. Lee, “Effects of Ni cladding layers on suppression of Ag agglomeration in Ag-based Ohmic contacts on p-GaN,” Appl. Phys. Lett. 95(6), 062108 (2009).
[Crossref]

X. Guo and E. F. Schubert, “Current crowding and optical saturation effects in GaInN/GaN light-emitting diodes grown on insulating substrates,” Appl. Phys. Lett. 78(21), 3337–3339 (2001).
[Crossref]

ECS J. Solid State Sci. Technol. (1)

X. Liu, N. Li, J. Hu, Y. Gao, R. Wang, and S. Zhou, “Comparative Study of Highly Reflective ITO/DBR and Ni/Ag ohmic Contacts for GaN-Based Flip-Chip Light-Emitting Diodes,” ECS J. Solid State Sci. Technol. 7(6), Q116–Q122 (2018).
[Crossref]

IEEE Electron Device Lett. (1)

W. C. Chong and K. M. Lau, “Performance enhancements of flip-chip light-emitting diodes with high-density n-type point-contacts,” IEEE Electron Device Lett. 35(10), 1049–1051 (2014).
[Crossref]

IEEE Photonics Technol. Lett. (1)

C. H. Lin, C. F. Lai, T. S. Ko, H. W. Huang, H. C. Kuo, Y. Y. Hung, K. M. Leung, C. C. Yu, R. J. Tsai, C. K. Lee, T. C. Lu, and S. C. Wang, “Enhancement of InGaN–GaN Indium-Tin-Oxide Flip-Chip Light-Emitting Diodes With TiO2-SiO2 Multilayer Stack Omnidirectional Reflector,” IEEE Photonics Technol. Lett. 18(19), 2050–2052 (2006).
[Crossref]

IEEE Trans. Electron Dev. (1)

S. Hwang and J. Shim, “A method for current spreading analysis and electrode pattern design in light-emitting diodes,” IEEE Trans. Electron Dev. 55(5), 1123–1128 (2008).
[Crossref]

J. Alloys Compd. (2)

T. H. Park, T. H. Lee, and T. G. Kim, “Al2O3/AlN/Al-based backside diffuse reflector for high-brightness 370-nm AlGaN ultraviolet light-emitting diodes,” J. Alloys Compd. 776, 1009–1015 (2019).
[Crossref]

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]

J. Mater. Res. (5)

K. O. Kese, Z. C. Li, and B. Bergman, “Influence of residual stress on elastic modulus and hardness of soda-lime glass measured by nanoindentation,” J. Mater. Res. 19(10), 3109–3119 (2004).
[Crossref]

T. Y. Tsui, W. C. Oliver, and G. M. Pharr, “Influences of stress on the measurement of mechanical properties using nanoindentation: Part I. Experimental studies in an aluminum alloy,” J. Mater. Res. 11, 752–759 (1996).
[Crossref]

Y. H. Lee and D. Kwon, “Residual stresses in DLC/Si and Au/Si systems: Application of a stress-relaxation model to the nanoindentation technique,” J. Mater. Res. 17, 901–906 (2002).
[Crossref]

T. Y. Tsui, W. C. Oliver, and G. M. Pharr, “Influences of stress on the measurement of mechanical properties using nanoindentation: Part I. Experimental studies in an aluminum alloy,” J. Mater. Res. 11(03), 752–759 (1996).
[Crossref]

A. Bolshakov, W. C. Oliver, and G. M. Pharr, “Influences of stress on the measurement of mechanical properties using nanoindentation: Part II. Finite element simulations,” J. Mater. Res. 11(03), 760–768 (1996).
[Crossref]

J. Phys. Condens. Matter (1)

J. K. Sheu and G. C. Chi, “The doping process and dopant characteristics of GaN,” J. Phys. Condens. Matter 14(22), R657 (2002).
[Crossref]

Jpn. J. Appl. Phys. (1)

N. Maeda, J. Yun, M. Jo, and H. Hirayama, “Enhancing the light-extraction efficiency of AlGaN deep-ultraviolet light-emitting diodes using highly reflective Ni/Mg and Rh as p-type electrodes,” Jpn. J. Appl. Phys. 57(4S), 04FH08 (2018).
[Crossref]

Mater. Charact. (1)

L. N. Zhu, B. S. Xu, H. D. Wang, and C. B. Wang, “Measurement of residual stress in quenched 1045 steel by the nanoindentation method,” Mater. Charact. 61(12), 1359–1362 (2010).
[Crossref]

Micromachines (Basel) (1)

S. Zhou, H. Xu, M. Liu, X. Liu, J. Zhao, N. Li, and S. Liu, “Effect of Dielectric Distributed Bragg Reflector on Electrical and Optical Properties of GaN-Based Flip-Chip Light-Emitting Diodes,” Micromachines (Basel) 9(12), 650 (2018).
[Crossref] [PubMed]

Nat. Commun. (1)

N. Han, T. V. Cuong, M. Han, B. D. Ryu, S. Chandramohan, J. B. Park, J. H. Kang, Y. J. Park, K. B. Ko, H. Y. Kim, H. K. Kim, J. H. Ryu, Y. S. Katharria, C. J. Choi, and C. H. Hong, “Improved heat dissipation in gallium nitride light-emitting diodes with embedded graphene oxide pattern,” Nat. Commun. 4, 1452 (2013).
[Crossref] [PubMed]

Nat. Photonics (2)

J. J. Wierer, A. David, and M. M. Megens, “III-nitride photonic-crystal light-emitting diodes with high extraction efficiency,” Nat. Photonics 3(3), 163–169 (2009).
[Crossref]

S. Pimputkar, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Prospects for LED lighting,” Nat. Photonics 3(4), 180–182 (2009).
[Crossref]

Nature (1)

F. A. Ponce and D. P. Bour, “Nitride-based semiconductors for blue and green light-emitting devices,” Nature 386(6623), 351–359 (1997).
[Crossref]

Opt. Express (2)

Phys. Rev. B Condens. Matter (1)

P. E. Blöchl, “Projector augmented-wave method,” Phys. Rev. B Condens. Matter 50(24), 17953–17979 (1994).
[Crossref] [PubMed]

Phys. Rev. B Condens. Matter Mater. Phys. (1)

K. T. Delaney, N. A. Spaldin, and C. G. Van de Walle, “Theoretical study of Schottky-barrier formation at epitaxial rare-earth-metal/semiconductor interfaces,” Phys. Rev. B Condens. Matter Mater. Phys. 81(16), 165312 (2010).
[Crossref]

Phys. Rev. Lett. (2)

A. Baldereschi, S. Baroni, and R. Resta, “Band Offsets in Lattice-Matched Heterojunctions: A Model and First-Principles Calculations for GaAs/AlAs,” Phys. Rev. Lett. 61(6), 734–737 (1988).
[Crossref] [PubMed]

J. P. Perdew, K. Burke, and M. Ernzerhof, “Generalized gradient approximation made simple,” Phys. Rev. Lett. 77(18), 3865–3868 (1996).
[Crossref] [PubMed]

Phys. Status Solidi., A Appl. Mater. Sci. (2)

J. Lv, C. Zheng, Q. Chen, S. Zhou, and S. Liu, “High power InGaN/GaN flip-chip LEDs with via-hole-based two-level metallization electrodes,” Phys. Status Solidi., A Appl. Mater. Sci. 213(12), 3150–3156 (2016).
[Crossref]

D. A. Zakheim, A. S. Pavluchenko, D. A. Bauman, K. A. Bulashevich, O. V. Khokhlev, and S. Y. Karpov, “Efficiency droop suppression in InGaN-based blue LEDs: Experiment and numerical modelling,” Phys. Status Solidi., A Appl. Mater. Sci. 209(3), 456–460 (2012).
[Crossref]

Proc. SPIE (1)

I. Eliashevich, Y. Li, A. Osinsky, C. A. Tran, M. G. Brown, and R. F. Karlicek, “InGaN blue light-emitting diodes with optimized n-GaN layer,” Proc. SPIE 3621, 28–36 (1999).
[Crossref]

Sci. Rep. (1)

H. Hu, S. Zhou, X. Liu, Y. Gao, C. Gui, and S. Liu, “Effects of GaN/AlGaN/Sputtered AlN nucleation layers on performance of GaN-based ultraviolet light-emitting diodes,” Sci. Rep. 7(1), 44627 (2017).
[Crossref] [PubMed]

Science (1)

E. F. Schubert and J. K. Kim, “Solid-state light sources getting smart,” Science 308(5726), 1274–1278 (2005).
[Crossref] [PubMed]

Scr. Mater. (1)

Y. H. Lee and D. Kwon, “Measurement of residual-stress effect by nanoindentation on elastically strained (100) W,” Scr. Mater. 49(5), 459–465 (2003).
[Crossref]

Solid-State Electron. (1)

H. Zhao, G. Liu, R. A. Arif, and 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 (1)

S. Liu and X. Luo, LED packaging for lighting applications: design, manufacturing, and testing (John Wiley & Sons, 2011).

Cited By

OSA participates in Crossref's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (15)

Fig. 1
Fig. 1 Top-view SEM images of the films before and after annealing at 600°C: (a, b) Ag (100 nm), (c, d) Ag (100 nm)/TiW (120 nm), (e, f) Ag (100 nm)/TiW (300 nm), and (g, h) Ag (100 nm)/TiW (120 nm)/Pt (10 nm)/TiW (90 nm)/Pt (10 nm)/TiW (90 nm)/Pt (100 nm) films. Nanoindentation tests on samlpes at 25°C before and after annealing at 200°C: (i) Examples of nano indents, (j) Comparison between hmax from Ag (100 nm)/TiW (120 nm), Ag (100 nm)/TiW (300 nm), and Ag (100 nm)/TiW (120 nm)/Pt (10 nm)/TiW (90 nm)/Pt (10 nm)/TiW (90 nm)/Pt (100 nm).
Fig. 2
Fig. 2 (a) Reflectance spectra of the as-deposited Ag (100 nm), Ag (100 nm)/TiW (300 nm), and Ag (100 nm)/TiW (120 nm)/Pt (10 nm)/TiW (90 nm)/Pt (10 nm)/TiW (90 nm)/Pt (100 nm) films at normal incidence. (b) Optical microscopy image of the Ag CTLM pads. (c) I-V characteristics of the Ag contact to the p-GaN layer when annealed at different temperatures. (d) I-V curves of measured for different gap spacings of the CTLM patterns for the Ag contacts deposited on p-GaN after annealing at 600°C. (e) The XPS depth profile of Ag/p-GaN contact without annealing treatment. (f) The XPS depth profile of Ag/p-GaN contact with 600°C annealing treatment.
Fig. 3
Fig. 3 The LDOS projected on each atomic layer of the GaN side. (a) Non-diffusion condition. (b) One Ag atom diffuses from layer5 to layer4. (c) Two Ag atoms diffuse from layer5 to layer4. (d) One Ag atom diffuses from layer6 to layer4 and from layer5 to layer3. (e) Two Ag atom diffuses from layer6 to layer4 and from layer5 to layer3. (f) Detailed LDOS in layer4 of GaN bilayers with different interfacial composition. (g) SBH and the change in average electrostatic potential across the interface ( Δ V ) for difference diffusion interfacial condition.
Fig. 4
Fig. 4 (a) Measured reflectance of ITO/DBR as a function of the wavelength at normal, 20°, 40°, 60°, and 80° angles of incidence. (b) Measured reflectance of ITO/DBR and Ag/TiW/Pt/TiW/Pt/TiW/Pt as a function of the incident angle at a wavelength of 460 nm. (c) Magnified cross-sectional TEM image of the Ag/TiW/Pt/TiW/Pt/TiW/Pt films. (d) EDX line-scan performed vertically along the Ag/TiW/Pt/TiW/Pt/TiW/Pt films in (c). (e) Magnified cross-sectional TEM image of the 14-pair TiO2/SiO2 double DBR stacks. This design contains two single TiO2/SiO2 DBR stacks; each single DBR stack includes seven pairs of alternating TiO2/SiO2 dielectric layers that are optimized for different central wavelength. (f) EDX line-scan performed vertically along the TiO2/SiO2 DBR in (e).
Fig. 5
Fig. 5 (a) Top-view SEM image of FCLED-I. (b) Cross-sectional SEM image of FCLED-I milled by an FIB along the A-A direction. (c) Cross-sectional SEM image of FCLED-I milled by an FIB along the B-B direction. (d) Top-view SEM image of FCLED-II. (e) Cross-sectional SEM image of FCLED-II milled by an FIB along the C-C direction. (f) Cross-sectional SEM image of FCLED-II milled by an FIB along the D-D direction. (g) Top-view SEM image of FCLED-III. (h) Cross-sectional SEM image of FCLED-III milled by an FIB along the E-E direction. (i) Cross-sectional SEM image of FCLED-III milled by an FIB along the F-F direction.
Fig. 6
Fig. 6 Simulated current density distributions in the InGaN/GaN MQWs active region of (a) FCLED-I, (b) FCLED-II, and (c) FCLED-III at 750 mA.
Fig. 7
Fig. 7 Measured intensity distributions of the light emitted from FCLED-I, FCLED-II, and FCLED-III at injection currents of (a,d,g) 500 mA, (b,e,h) 750 mA, and (c,f,i) 1000 mA.
Fig. 8
Fig. 8 (a) I-V characteristics of the three FCLEDs: FCLED-I, FCLED-II, and FCLED-III. The inset figure shows the electroluminescence spectrum of the FCLED (b) LOP and EQE as a function of injection current for FCLED-I, FCLED-II, and FCLED-III. (c) Far-field emission pattern of the three FCLEDs: FCLED-I, FCLED-II, and FCLED-III. (d) Optical degradation test of the FCLEDs aged at 85°C under the current of 1000 mA.
Fig. 9
Fig. 9 (a) Cross-sectional TEM image of GaN-based LED epitaxial structure. (b) Schematic illustration of GaN-based LED epitaxial structure. (c) Magnified cross-sectional TEM image of GaN epitaxial structure including p-GaN, InGaN/GaN MQWs, and InGaN/GaN SL. (d) Magnified cross-sectional TEM image of the InGaN/GaN MQWs marked by the red square in (c). (e) Magnified cross-sectional TEM image of InGaN/GaN SL marked by the blue square in (c).
Fig. 10
Fig. 10 Schematic illustration of the fabrication process flow for FCLED-I. The chip dimensions of FCLED-I are 45 × 45 mil2.
Fig. 11
Fig. 11 Schematic illustration of the fabrication process flow for FCLED-II. The chip dimensions of FCLED-II are 45 × 45 mil2.
Fig. 12
Fig. 12 Schematic illustration of the fabrication process flow for FCLED-III. The chip dimensions of FCLED-III are 45 × 45 mil2.
Fig. 13
Fig. 13 Schematics of the effect of residual stress on nanoindentation tests: (a) The indentation on stress-free specimens; (b) and (c) The effect of compression and tension stress on the nanoindenation tests; (d) The comparison of load-depth curves from nanoindentation tests on specimens under different stress states.
Fig. 14
Fig. 14 Side view of geometries of Ag(111)/GaN(0001) interface. (a) Non-diffusion condition. (b) One Ag atom diffuses from layer5 to layer4; (c) Two Ag atoms diffuse from layer5 to layer4. (d) One Ag atom diffuses from layer6 to layer4 and from layer5 to layer3. (e) Two Ag atoms diffuse from layer6 to layer4 and from layer5 to layer3. (f) Top view of geometries of Ag(111)/GaN(0001) interface.
Fig. 15
Fig. 15 (a) Reflectance of the single DBR stack at different incident angles. (b) Reflectance of the single DBR stack with increasing thickness of TiO2 and SiO2 dielectric layers.

Tables (1)

Tables Icon

Table 1 Current density distribution in the active region of the FCLEDs at 500, 750, and 1000 mA.

Equations (1)

Equations on this page are rendered with MathJax. Learn more.

Φ p = Δ V + E F E V B M

Metrics