Al-Rich III-Nitride Materials and Ultraviolet Light-Emitting Diodes

  • Jianchang Yan
  • Junxi Wang
  • Yuhuai Liu
  • Jinmin Li
Part of the Solid State Lighting Technology and Application Series book series (SSLTA, volume 4)


Aluminum nitride (AlN) material is commonly used as a crucial template for the growth of high-quality Al-rich III-nitride materials and high-performance deep-ultraviolet light-emitting diodes (DUV LEDs). In this chapter, the heteroepitaxy of AlN film by MOVPE and the development of AlN epitaxy techniques on sapphire substrates are discussed. The structural design for efficient DUV LEDs is then introduced. Since bulk AlN substrates are a perfect candidate for AlGaN-based DUV LEDs due to similar thermal expansion coefficients and relatively small lattice mismatches, we also discussed AlN homoepitaxy, pseudomorphic AlGaN, and DUV LEDs on AlN substrates. The limited light extraction efficiency (LEE) is another obstacle for power DUV LEDs and their applications. The intrinsic Al-rich-induced optical polarization effect and related methods for improving the LEE are presented.



The author acknowledges contributions of Qingqing Wu and Jiankun Yang for AlN material growth, Lili Sun for structural design for efficient DUV LEDs, and Yanan Guo for the light exaction issues.


  1. 1.
    C.H. Chen et al., A study of parasitic reactions between NH3 and TMGa or TMAI. J. Electron. Mater. 25(6), 1004–1008 (1996)MathSciNetCrossRefGoogle Scholar
  2. 2.
    M.A. Khan et al., III-nitride UV devices. Jpn. J. Appl. Phys. 44(10), 7191–7206 (2005)CrossRefGoogle Scholar
  3. 3.
    T. Uchida, K. Kusakabe, K. Ohkawa, Influence of polymer formation on metalorganic vapor-phase epitaxial growth of AlN. J. Cryst. Growth 304(1), 133–140 (2007)CrossRefGoogle Scholar
  4. 4.
    D.G. Zhao et al., Parasitic reaction and its effect on the growth rate of AlN by metalorganic chemical vapor deposition. J. Cryst. Growth 289(1), 72–75 (2006)CrossRefGoogle Scholar
  5. 5.
    S. Kim et al., Growth of AlGaN epilayers related gas-phase reactions using TPIS-MOCVD. J. Cryst. Growth 245(3–4), 247–253 (2002)CrossRefGoogle Scholar
  6. 6.
    J.R. Creighton, G.T. Wang, Kinetics of metal organic-ammonia adduct decomposition: Implications for group-III nitride MOCVD. J. Phys. Chem. A 109(46), 10554–10562 (2005)CrossRefGoogle Scholar
  7. 7.
    J.R. Creighton, G.T. Wang, M.E. Coltrin, Fundamental chemistry and modeling of group-III nitride MOVPE. J. Cryst. Growth 298, 2–7 (2007)CrossRefGoogle Scholar
  8. 8.
    H. Yang et al., Alleviation of parasitic reactions for III-nitride epitaxy in MOCVD with a spatial separated source delivery method by controlling the main reaction type. J. Cryst. Growth 465, 1–5 (2017)CrossRefGoogle Scholar
  9. 9.
    R. Zuo et al., Influence of gas mixing and heating on gas-phase reactions in GaN MOCVD growth. ECS J. Solid State Sci. Technol. 1(1), P46–P53 (2012)CrossRefGoogle Scholar
  10. 10.
    T.G. Mihopoulos, V. Gupta, K.F. Jensen, A reaction-transport model for AlGaN MOVPE growth. J. Cryst. Growth 195(1–4), 733–739 (1998)CrossRefGoogle Scholar
  11. 11.
    R.P. Parikh, R.A. Adomaitis, An overview of gallium nitride growth chemistry and its effect on reactor design: Application to a planetary radial-flow CVD system. J. Cryst. Growth 286(2), 259–278 (2006)CrossRefGoogle Scholar
  12. 12.
    H. Simka et al., Computational chemistry predictions of reaction processes in organometallic vapor phase epitaxy. Prog. Cryst. Growth Charact. Mater. 35(2–4), 117–149 (1997)CrossRefGoogle Scholar
  13. 13.
    R.M. Watwe, J.A. Dumesic, T.F. Kuech, Gas-phase chemistry of metalorganic and nitrogen-bearing compounds. J. Cryst. Growth 221, 751–757 (2000)CrossRefGoogle Scholar
  14. 14.
    G.T. Wang, J.R. Creighton, Complex formation of trimethylaluminum and trimethylgallium with ammonia: Evidence for a hydrogen-bonded adduct. J. Phys. Chem. A 110(3), 1094–1099 (2006)CrossRefGoogle Scholar
  15. 15.
    K. Nakamura et al., Quantum chemical study of parasitic reaction in III-V nitride semiconductor crystal growth. J. Organomet. Chem. 611(1–2), 514–524 (2000)CrossRefGoogle Scholar
  16. 16.
    A. Demchuk, S. Simpson, B. Koplitz, Exploration of the laser-assisted clustering and reactivity of trimethylaluminum with and without NH3. Chem. A Eur. J. 107(11), 1727–1733 (2003)Google Scholar
  17. 17.
    J. Müller et al., Structure of ammonia trimethylalane (Me3Al-NH3): Microwave spectroscopy, x-ray powder diffraction, and ab initio calculations. J. Am. Chem. Soc. 121(19), 4647–4652 (1999)CrossRefGoogle Scholar
  18. 18.
    A.S. Lisovenko, K. Morokuma, A.Y. Timoshkin, Initial gas phase reactions between Al(CH3)3/AlH3 and ammonia: Theoretical study. J. Phys. Chem. A 119(4), 744–751 (2015)CrossRefGoogle Scholar
  19. 19.
    F.C. Sauls, L.V. Interrante, Coordination compounds of aluminum as precursors to aluminum nitride. Coord. Chem. Rev. 128(1–2), 193–207 (1993)CrossRefGoogle Scholar
  20. 20.
    F.C. Sauls, L.V. Interrante, Z.P. Jiang, ME3AL.NH3 formation and pyrolytic methane loss - thermodynamics, kinetics, and mechanism. Inorg. Chem. 29(16), 2989–2996 (1990)CrossRefGoogle Scholar
  21. 21.
    C.H. Henricks, D. Duffy, D.P. Eyman, Lewis acidity of alanes. Interactions of trimethylalane with amines ethers and phosphines. Inorg. Chem. 7(6), 1047–1051 (1968)CrossRefGoogle Scholar
  22. 22.
    C.C. Amato, J.B. Hudson, L.V. Interrante, Identification of the gas-phase products which occur during the deposition of AIN using the organometallic percursor: [(CH3)2AINH2]3. Appl. Surf. Sci. 54, 18–24 (1992)CrossRefGoogle Scholar
  23. 23.
    J. Müller, Aminodimethylalane (Me2AlNH2): Matrix isolation andab InitioCalculations. J. Am. Chem. Soc. 118(27), 6370–6376 (1996)CrossRefGoogle Scholar
  24. 24.
    Y.S. Hiraoka, M. Mashita, Ab initio study on the dimer structures of trimethylaluminum and dimethylaluminumhydride. J. Cryst. Growth 145(1–4), 473–477 (1994)CrossRefGoogle Scholar
  25. 25.
    K. Sekiguchi et al., Thermodynamic considerations of the vapor phase reactions in III-nitride metal organic vapor phase epitaxy. Jpn. J. Appl. Phys. 56(4S), 04CJ04 (2017)CrossRefGoogle Scholar
  26. 26.
    D. Sengupta et al., Combined ab initio quantum chemistry and computational fluid dynamics calculations for prediction of gallium nitride growth. J. Cryst. Growth 279(3–4), 369–382 (2005)CrossRefGoogle Scholar
  27. 27.
    R. Zuo et al., Quantum chemistry study on the adduct reaction paths as functions of temperature in GaN/AlN MOVPE growth. ECS J. Solid State Sci. Technol. 5(12), P667–P673 (2016)CrossRefGoogle Scholar
  28. 28.
    Y. Inagaki, T. Kozawa, Chemical reaction pathways for MOVPE growth of aluminum nitride. ECS J. Solid State Sci. Technol. 5(2), P73–P75 (2016)CrossRefGoogle Scholar
  29. 29.
    A.V. Lobanova et al., Growth conditions and surface morphology of AlN MOVPE. J. Cryst. Growth 310(23), 4935–4938 (2008)CrossRefGoogle Scholar
  30. 30.
    R. Bouveyron, M.B. Charles, Growth by MOCVD of In(Ga)AIN alloys, and a study of gallium contamination in these layers under nitrogen and hydrogen carrier gas. J. Cryst. Growth 464, 105–111 (2017)CrossRefGoogle Scholar
  31. 31.
    J. Stellmach et al., High aluminium content and high growth rates of AlGaN in a close-coupled showerhead MOVPE reactor. J. Cryst. Growth 315(1), 229–232 (2011)CrossRefGoogle Scholar
  32. 32.
    H. Hirayama, S. Fujikawa, N. Kamata, Recent progress in AlGaN-based deep-UV LEDs. Electron. Commun. Jpn. 98(5), 1–8 (2015)CrossRefGoogle Scholar
  33. 33.
    J.R. Grandusky et al., 270 nm pseudomorphic ultraviolet light-emitting diodes with over 60 mW continuous wave output power. Appl. Phys. Express 6(3), 032101 (2013)CrossRefGoogle Scholar
  34. 34.
    J.P. Zhang et al., Pulsed atomic-layer epitaxy of ultrahigh-quality AlxGa1-xN structures for deep ultraviolet emissions below 230 nm. Appl. Phys. Lett. 81(23), 4392–4394 (2002)CrossRefGoogle Scholar
  35. 35.
    H.M. Foronda et al., Improving source efficiency for aluminum nitride grown by metal organic chemical vapor deposition. Semicond. Sci. Technol. 31(8), 085003 (2016)CrossRefGoogle Scholar
  36. 36.
    R.B. Chung et al., Growth and impurity characterization of AlN on (0001) sapphire grown by spatially pulsed MOCVD. Phys. Status Solidi A Appl. Mater. Sci. 213(4), 851–855 (2016)CrossRefGoogle Scholar
  37. 37.
    M.J. Lai et al., Improvement of crystal quality of AlN grown on sapphire substrate by MOCVD. Cryst. Res. Technol. 45(7), 703–706 (2010)CrossRefGoogle Scholar
  38. 38.
    M. Kneissl, III-Nitride Ultraviolet Emitters: Technology and Applications (Springer, Berlin, 2017)Google Scholar
  39. 39.
    H.-C. Seo, I. Petrov, K. Kim, Structural properties of AlN grown on sapphire at plasma self-heating conditions using reactive magnetron sputter deposition. J. Electron. Mater. 39(8), 1146–1151 (2010)CrossRefGoogle Scholar
  40. 40.
    Y.R. Lin, S.T. Wu, Growth of aluminum nitride films at low temperature. J. Cryst. Growth 252(1–3), 433–439 (2003)CrossRefGoogle Scholar
  41. 41.
    S.Y. Karpov, Y.N. Makarov, Dislocation effect on light emission efficiency in gallium nitride. Appl. Phys. Lett. 81(25), 4721–4723 (2002)CrossRefGoogle Scholar
  42. 42.
    A. Severino, F. Iucolano, Impact of growth conditions on stress and quality of aluminum nitride (AlN) thin buffer layers. Phys. Status Solidi B Basic Solid State Phys. 253(5), 801–808 (2016)CrossRefGoogle Scholar
  43. 43.
    X. Rong et al., Residual stress in AlN films grown on sapphire substrates by molecular beam epitaxy. Superlattice. Microst. 93, 27–31 (2016)CrossRefGoogle Scholar
  44. 44.
    P. Dong et al., AlGaN-based deep ultraviolet light-emitting diodes grown on nano-patterned sapphire substrates with significant improvement in internal quantum efficiency. J. Cryst. Growth 395, 9–13 (2014)CrossRefGoogle Scholar
  45. 45.
    Y. Li et al., Defect-reduced green GaInN/GaN light-emitting diode on nanopatterned sapphire. Appl. Phys. Lett. 98(15), 151102 (2011)CrossRefGoogle Scholar
  46. 46.
    Y. Zhang et al., Defect reduction in overgrown semi-polar (11-22) GaN on a regularly arrayed micro-rod array template. AIP Adv. 6(2), 025201 (2016)CrossRefGoogle Scholar
  47. 47.
    V. Adivarahan et al., Robust 290 nm emission light emitting diodes over pulsed laterally overgrown AlN. Jpn. J. Appl. Phys. Part 2 Lett. Express Lett. 46(36–40), L877–L879 (2007)CrossRefGoogle Scholar
  48. 48.
    M. Imura et al., Microstructure of epitaxial lateral overgrown AlN on trench-patterned AlN template by high-temperature metal-organic vapor phase epitaxy. Appl. Phys. Lett. 89(22), 221901 (2006)CrossRefGoogle Scholar
  49. 49.
    M. Conroy et al., Epitaxial lateral overgrowth of AlN on self-assembled patterned nanorods. J. Mater. Chem. C 3(2), 431–437 (2015)CrossRefGoogle Scholar
  50. 50.
    C. Xiang et al., Improved crystalline quality of AlN by epitaxial lateral overgrowth using two-phase growth method for deep-ultraviolet stimulated emission. IEEE Photon. J. 8(5), 2300211 (2016)CrossRefGoogle Scholar
  51. 51.
    M.I. Nathan, The blue laser diode. GaN based light emitters and lasers. Science 277(5322), 46–47 (1997)CrossRefGoogle Scholar
  52. 52.
    H. Miyake et al., Annealing of an AlN buffer layer in N2–CO for growth of a high-quality AlN film on sapphire. Appl. Phys. Express 9(2), 025501 (2016)CrossRefGoogle Scholar
  53. 53.
    M. Ohtsuka, H. Takeuchi, H. Fukuyama, Effect of sputtering pressure on crystalline quality and residual stress of AlN films deposited at 823K on nitrided sapphire substrates by pulsed DC reactive sputtering. Jpn. J. Appl. Phys. 55(5S), 05FD08 (2016)CrossRefGoogle Scholar
  54. 54.
    A.M. Soomro et al., Modified pulse growth and misfit strain release of an AlN heteroepilayer with a mg–Si codoping pair by MOCVD. J. Phys. D. Appl. Phys. 49(11), 115110 (2016)CrossRefGoogle Scholar
  55. 55.
    D.G. Zhao et al., Effect of dual buffer layer structure on the epitaxial growth of AlN on sapphire. J. Alloys Compd. 544, 94–98 (2012)CrossRefGoogle Scholar
  56. 56.
    S.C. Chen et al., Defect reduction in AlN epilayers grown by MOCVD via intermediate-temperature interlayers. J. Electron. Mater. 44(1), 217–221 (2015)CrossRefGoogle Scholar
  57. 57.
    J. Yan et al., AlGaN-based deep-ultraviolet light-emitting diodes grown on high-quality AlN template using MOVPE. J. Cryst. Growth 414, 254–257 (2015)CrossRefGoogle Scholar
  58. 58.
    P. Vennegues et al., Influence of in situ sapphire surface preparation and carrier gas on the growth mode of GaN in MOVPE. J. Cryst. Growth 187(2), 167–177 (1998)CrossRefGoogle Scholar
  59. 59.
    O. Klein et al., TEM investigations on growth interrupted samples for the correlation of the dislocation propagation and growth mode variations in AlGaN deposited on SiNx interlayers. J. Cryst. Growth 324(1), 63–72 (2011)CrossRefGoogle Scholar
  60. 60.
    K. Forghani et al., High quality AlGaN epilayers grown on sapphire using SiNx interlayers. J. Cryst. Growth 315(1), 216–219 (2011)CrossRefGoogle Scholar
  61. 61.
    H.-M. Wang et al., AlN/AlGaN superlattices as dislocation filter for low-threading-dislocation thick AlGaN layers on sapphire. Appl. Phys. Lett. 81(4), 604 (2002)CrossRefGoogle Scholar
  62. 62.
    J.P. Zhang et al., Crack-free thick AlGaN grown on sapphire using AlN/AlGaN superlattices for strain management. Appl. Phys. Lett. 80(19), 3542 (2002)CrossRefGoogle Scholar
  63. 63.
    K.P. Streubel et al., MOVPE growth for UV-LEDs. Proc. SPIE 7231, 72310G (2009)CrossRefGoogle Scholar
  64. 64.
    M. Imura et al., High-temperature metal-organic vapor phase epitaxial growth of AlN on sapphire by multi transition growth mode method varying V/III ratio. Jpn. J.Appl. Phys. Part 1 Regular Papers Brief. Commun. Rev. Papers 45(11), 8639–8643 (2006)CrossRefGoogle Scholar
  65. 65.
    M. Imura et al., Annihilation mechanism of threading dislocations in AlN grown by growth form modification method using V/III ratio. J. Cryst. Growth 300(1), 136–140 (2007)CrossRefGoogle Scholar
  66. 66.
    T.Y. Wang et al., Defect annihilation mechanism of AlN buffer structures with alternating high and low V/III ratios grown by MOCVD. CrystEngComm 18(47), 9152–9159 (2016)CrossRefGoogle Scholar
  67. 67.
    M. Shatalov et al., AlGaN deep-ultraviolet light-emitting diodes with external quantum efficiency above 10%. Appl. Phys. Express 5(8), 082101 (2012)CrossRefGoogle Scholar
  68. 68.
    R.G. Banal, M. Funato, Y. Kawakamia, Initial nucleation of AlN grown directly on sapphire substrates by metal-organic vapor phase epitaxy. Appl. Phys. Lett. 92(24), 241905 (2008)CrossRefGoogle Scholar
  69. 69.
    R.G. Banal, M. Funato, Y. Kawakami, Characteristics of high Al-content AlGaN/AlN quantum wells fabricated by modified migration enhanced epitaxy. Phys. Status Solidi C Curr. Topics Solid State Phys. 7(7–8), 2111–2114 (2010)Google Scholar
  70. 70.
    W.G. Hu et al., Using different carrier gases to control AlN film stress and the effect on morphology, structural properties and optical properties. J. Phys. D Appl. Phys. 40(23), 7462–7466 (2007)CrossRefGoogle Scholar
  71. 71.
    M. Kneissl et al., Advances in group III-nitride-based deep UV light-emitting diode technology. Semicond. Sci. Technol. 26(1), 014036 (2011)CrossRefGoogle Scholar
  72. 72.
    K. Ban et al., Internal quantum efficiency of whole-composition-range AlGaN multiquantum wells. Appl. Phys. Express 4(5), 052101 (2011)CrossRefGoogle Scholar
  73. 73.
    Y. Zhao et al., Characterization of AlGaN on GaN template grown by MOCVD. Proc. SPIE 6841, 68410K (2007)CrossRefGoogle Scholar
  74. 74.
    S. Kamiyama et al., Low-temperature-deposited AlGaN interlayer for improvement of AlGaN_GaN heterostructure. J. Cryst. Growth 223, 83–91 (2001)CrossRefGoogle Scholar
  75. 75.
    H. Amano et al., Metalorganic vapor phase epitaxial growth of a high quality GaN film using an AlN buffer layer. Appl. Phys. Lett. 48(5), 353–355 (1986)CrossRefGoogle Scholar
  76. 76.
    M. Asif Khan et al., Low pressure metalorganic chemical vapor deposition of AIN over sapphire substrates. Appl. Phys. Lett. 61(21), 2539–2541 (1992)CrossRefGoogle Scholar
  77. 77.
    M. Asif Khan et al., Atomic layer epitaxy of GaN over sapphire using switched metalorganic chemical vapor deposition. Appl. Phys. Lett. 60(11), 1366–1368 (1992)CrossRefGoogle Scholar
  78. 78.
    M. Asif Khan et al., GaN/AlN digital alloy short-period superlattices by switched atomic layer metalorganic chemical vapor deposition. Appl. Phys. Lett. 63(25), 3470–3472 (1993)CrossRefGoogle Scholar
  79. 79.
    O. Ambacher, Growth and applications of Group III-nitrides. J. Phys. D. Appl. Phys. 31(20), 2653–2170 (1998)CrossRefGoogle Scholar
  80. 80.
    J. Zhang et al., AlGaN deep-ultraviolet light-emitting diodes. Jpn. J. Appl. Phys. 44(10), 7250–7253 (2005)CrossRefGoogle Scholar
  81. 81.
    H. Hirayama et al., Milliwatt power 270 nm-band AlGaN deep-UV LEDs fabricated on ELO-AlN templates. Phys. Status Solidi C 6(S2), S474–S477 (2009)CrossRefGoogle Scholar
  82. 82.
    Y. Jianchang et al., High quality AlGaN grown on a high temperature AIN template by MOCVD. J. Semicond. 30(10), 103001 (2009)CrossRefGoogle Scholar
  83. 83.
    P. Dong et al., 282-nm AlGaN-based deep ultraviolet light-emitting diodes with improved performance on nano-patterned sapphire substrates. Appl. Phys. Lett. 102(24), 241113 (2013)CrossRefGoogle Scholar
  84. 84.
    V. Adivarahan et al., Sub-milliwatt power III-N light emitting diodes at 285 nm. Jpn. J. Appl. Phys. 41(Part 2, No. 4B), L435–L436 (2002)CrossRefGoogle Scholar
  85. 85.
    J.P. Zhang et al., High-quality AlGaN layers over pulsed atomic-layer epitaxially grown AlN templates for deep ultraviolet light-emitting diodes. J. Electron. Mater. 32(5), 364–370 (2003)CrossRefGoogle Scholar
  86. 86.
    P. Cantu et al., Metalorganic chemical vapor deposition of highly conductive Al0.65Ga0.35N films. Appl. Phys. Lett. 82(21), 3683–3685 (2003)CrossRefGoogle Scholar
  87. 87.
    M.L. Nakarmi et al., Transport properties of highly conductive n-type Al-rich AlxGa1−xN(x⩾0.7). Appl. Phys. Lett. 85(17), 3769–3771 (2004)CrossRefGoogle Scholar
  88. 88.
    K. Zhu et al., Silicon doping dependence of highly conductive n-type Al0.7Ga0.3N. Appl. Phys. Lett. 85(20), 4669–4671 (2004)CrossRefGoogle Scholar
  89. 89.
    Y. Taniyasu, M. Kasu, T. Makimoto, Electrical conduction properties of n-type Si-doped AlN with high electron mobility (>100cm2V−1s−1). Appl. Phys. Lett. 85(20), 4672–4674 (2004)CrossRefGoogle Scholar
  90. 90.
    J. Hwang et al., Si doping of high-Al-mole fraction AlxGa1−xN alloys with rf plasma-induced molecular-beam-epitaxy. Appl. Phys. Lett. 81(27), 5192–5194 (2002)CrossRefGoogle Scholar
  91. 91.
    R. Collazo et al., Progress on n-type doping of AlGaN alloys on AlN single crystal substrates for UV optoelectronic applications. Phys. Status Solidi C 8(7–8), 2031–2033 (2011)CrossRefGoogle Scholar
  92. 92.
    M. Katsuragawa et al., Thermal ionization energy of Si and Mg in AlGaN. J. Cryst. Growth 189/190, 528–531 (1998)CrossRefGoogle Scholar
  93. 93.
    S.R. Jeon et al., Investigation of Mg doping in high-Al content p-type AlxGa1−xN (0.3<x<0.5). Appl. Phys. Lett. 86(8), 082107 (2005)CrossRefGoogle Scholar
  94. 94.
    M.L. Nakarmi et al., Enhanced p-type conduction in GaN and AlGaN by Mg-δ-doping. Appl. Phys. Lett. 82(18), 3041 (2003)CrossRefGoogle Scholar
  95. 95.
    J. Simon et al., Polarization-induced hole doping in wide-band-gap uniaxial semiconductor heterostructures. Science 327(5961), 60–64 (2010)CrossRefGoogle Scholar
  96. 96.
    S. Marcinkevičius et al., Intrinsic electric fields in AlGaN quantum wells. Appl. Phys. Lett. 90(8), 081914 (2007)CrossRefGoogle Scholar
  97. 97.
    A. Fujioka et al., Improvement in output power of 280-nm deep ultraviolet light-emitting diode by using AlGaN multi quantum wells. Appl. Phys. Express 3(4), 041001 (2010)CrossRefGoogle Scholar
  98. 98.
    S. Sumiya et al., AlGaN-based deep ultraviolet light-emitting diodes grown on epitaxial AlN/sapphire templates. Jpn. J. Appl. Phys. 47(1), 43–46 (2008)CrossRefGoogle Scholar
  99. 99.
    H. Hirayama et al., Marked enhancement in the efficiency of deep-ultraviolet AlGaN light-emitting diodes by using a multiquantum-barrier Electron blocking layer. Appl. Phys. Express 3(3), 031002 (2010)CrossRefGoogle Scholar
  100. 100.
    J. Yan et al., Improved performance of UV-LED by p-AlGaN with graded composition. Phys. Status Solidi C 8(2), 461–463 (2011)CrossRefGoogle Scholar
  101. 101.
    F. Mehnke et al., Efficient charge carrier injection into sub-250 nm AlGaN multiple quantum well light emitting diodes. Appl. Phys. Lett. 105(5), 051113 (2014)CrossRefGoogle Scholar
  102. 102.
    T. Takano et al., Deep-ultraviolet light-emitting diodes with external quantum efficiency higher than 20% at 275 nm achieved by improving light-extraction efficiency. Appl. Phys. Express 10(3), 031002 (2017)CrossRefGoogle Scholar
  103. 103.
    L.M. Svedberg, K.C. Arndt, M.J. Cima, Corrosion of aluminum nitride (AlN) in aqueous cleaning solutions. J. Am. Ceram. Soc. 83(1), 41–46 (2000)CrossRefGoogle Scholar
  104. 104.
    R. Dalmau et al., X-ray photoelectron spectroscopy characterization of aluminum nitride surface oxides: Thermal and hydrothermal evolution. J. Electron. Mater. 36(4), 414–419 (2007)CrossRefGoogle Scholar
  105. 105.
    S.A. Nikishin et al., Short-period superlattices of AlN∕Al[sub 0.08]Ga[sub 0.92]N grown on AlN substrates. Appl. Phys. Lett. 85(19), 4355 (2004)CrossRefGoogle Scholar
  106. 106.
    A. Rice et al., Surface preparation and homoepitaxial deposition of AlN on (0001)-oriented AlN substrates by metalorganic chemical vapor deposition. J. Appl. Phys. 108(4), 043510 (2010)CrossRefGoogle Scholar
  107. 107.
    R. Dalmau et al., Growth and characterization of AlN and AlGaN epitaxial films on AlN single crystal substrates. J. Electrochem. Soc. 158(5), H530 (2011)CrossRefGoogle Scholar
  108. 108.
    H.J. Kim et al., Modulated precursor flow epitaxial growth of AlN layers on native AlN substrates by metal-organic chemical vapor deposition. Appl. Phys. Lett. 93(2), 022103 (2008)CrossRefGoogle Scholar
  109. 109.
    J.R. Grandusky et al., Pseudomorphic growth of thick n-type AlxGa1-xN layers on low-defect-density bulk AlN substrates for UV LED applications. J. Cryst. Growth 311(10), 2864–2866 (2009)CrossRefGoogle Scholar
  110. 110.
    Z. Ren et al., Heteroepitaxy of AlGaN on bulk AlN substrates for deep ultraviolet light emitting diodes. Appl. Phys. Lett. 91(5), 051116 (2007)CrossRefGoogle Scholar
  111. 111.
    J.W. Matthews, A.E. Blakeslee, Defects in epitaxial multilayers. I. Misfit dislocations. J. Cryst. Growth 27, 118–125 (1974)Google Scholar
  112. 112.
    J.R. Grandusky et al., Properties of mid-ultraviolet light emitting diodes fabricated from Pseudomorphic layers on bulk Aluminum nitride substrates. Appl. Phys. Express 3(7), 072103 (2010)CrossRefGoogle Scholar
  113. 113.
    Z. Bryan et al., High internal quantum efficiency in AlGaN multiple quantum wells grown on bulk AlN substrates. Appl. Phys. Lett. 106(14), 142107 (2015)CrossRefGoogle Scholar
  114. 114.
    C.G. Moe et al., High-power pseudomorphic mid-ultraviolet light-emitting diodes with improved efficiency and lifetime. Proc. SPIE 8986, 89861V (2014)CrossRefGoogle Scholar
  115. 115.
    Y. Kumagai et al., Preparation of a freestanding AlN substrate from a thick AlN layer grown by hydride vapor phase epitaxy on a bulk AlN substrate prepared by physical vapor transport. Appl. Phys. Express 5(5), 055504 (2012)CrossRefGoogle Scholar
  116. 116.
    T. Kinoshita et al., Deep-ultraviolet light-emitting diodes fabricated on AlN substrates prepared by hydride vapor phase epitaxy. Appl. Phys. Express 5(12), 122101 (2012)CrossRefGoogle Scholar
  117. 117.
    S.-i. Inoue, N. Tamari, M. Taniguchi, 150 mW deep-ultraviolet light-emitting diodes with large-area AlN nanophotonic light-extraction structure emitting at 265 nm. Appl. Phys. Lett. 110(14), 141106 (2017)CrossRefGoogle Scholar
  118. 118.
    S.-i. Inoue et al., Light extraction enhancement of 265 nm deep-ultraviolet light-emitting diodes with over 90 mW output power via an AlN hybrid nanostructure. Appl. Phys. Lett. 106(13), 131104 (2015)CrossRefGoogle Scholar
  119. 119.
    J.J. Wierer et al., Influence of optical polarization on the improvement of light extraction efficiency from reflective scattering structures in AlGaN ultraviolet light-emitting diodes. Appl. Phys. Lett. 105(6), 061106 (2014)CrossRefGoogle Scholar
  120. 120.
    T. Kolbe et al., Optical polarization characteristics of ultraviolet (In)(Al)GaN multiple quantum well light emitting diodes. Appl. Phys. Lett. 97, 171105 (2010)CrossRefGoogle Scholar
  121. 121.
    H.Y. Ryu et al., Investigation of light extraction efficiency in AlGaN deep-ultraviolet light-emitting diodes. Appl. Phys. Express 6(6), 062101 (2013)CrossRefGoogle Scholar
  122. 122.
    J. Li et al., Band structure and fundamental optical transitions in wurtzite AlN. Appl. Phys. Lett. 83(25), 5163 (2003)CrossRefGoogle Scholar
  123. 123.
    K.B. Nam et al., Unique optical properties of AlGaN alloys and related ultraviolet emitters. Appl. Phys. Lett. 84(25), 5264 (2004)CrossRefGoogle Scholar
  124. 124.
    T.K. Sharma, D. Naveh, E. Towe, Strain-driven light-polarization switching in deep ultraviolet nitride emitters. Phys. Rev. B 84(3), 035305 (2011)CrossRefGoogle Scholar
  125. 125.
    J.E. Northrup et al., Effect of strain and barrier composition on the polarization of light emission from AlGaN/AlN quantum wells. Appl. Phys. Lett. 100(2), 021101 (2012)MathSciNetCrossRefGoogle Scholar
  126. 126.
    Z. Bryan et al., Strain dependence on polarization properties of AlGaN and AlGaN-based ultraviolet lasers grown on AlN substrates. Appl. Phys. Lett. 106(23), 232101 (2015)CrossRefGoogle Scholar
  127. 127.
    J.J. Wierer et al., Effect of thickness and carrier density on the optical polarization of Al0.44Ga0.56N/Al0.55Ga0.45N quantum well layers. J. Appl. Phys. 115(17), 174501 (2014)CrossRefGoogle Scholar
  128. 128.
    T.M. Al Tahtamouni, J.Y. Lin, H.X. Jiang, Optical polarization in c-plane Al-rich AlN/AlxGa1-xN single quantum wells. Appl. Phys. Lett. 101(4), 042103 (2012)CrossRefGoogle Scholar
  129. 129.
    R. Banal, M. Funato, Y. Kawakami, Optical anisotropy in [0001]-oriented AlxGa1−xN/AlN quantum wells (x>0.69). Phys. Rev. B 79(12), 121308(R) (2009)CrossRefGoogle Scholar
  130. 130.
    M. Hou et al., Effect of injection current on the optical polarization of AlGaN-based ultraviolet light-emitting diodes. Opt. Express 22(16), 19589 (2014)CrossRefGoogle Scholar
  131. 131.
    S.-H. Park, J.-I. Shim, Carrier density dependence of polarization switching characteristics of light emission in deep-ultraviolet AlGaN/AlN quantum well structures. Appl. Phys. Lett. 102(22), 221109 (2013)CrossRefGoogle Scholar
  132. 132.
    T. Kolbe et al., Effect of temperature and strain on the optical polarization of (In)(Al)GaN ultraviolet light emitting diodes. Appl. Phys. Lett. 99(26), 261105 (2011)CrossRefGoogle Scholar
  133. 133.
    C. Reich et al., Strongly transverse-electric-polarized emission from deep ultraviolet AlGaN quantum well light emitting diodes. Appl. Phys. Lett. 107(14), 142101 (2015)CrossRefGoogle Scholar
  134. 134.
    M. Khizar et al., Nitride deep-ultraviolet light-emitting diodes with microlens array. Appl. Phys. Lett. 86(17), 173504 (2005)CrossRefGoogle Scholar
  135. 135.
    C. Pernot et al., Improved efficiency of 255–280 nm AlGaN-based light-emitting diodes. Appl. Phys. Express 3(6), 061004 (2010)CrossRefGoogle Scholar
  136. 136.
    C.-H. Chan et al., Improved output power of GaN-based light-emitting diodes grown on a nanopatterned sapphire substrate. Appl. Phys. Lett. 95(1), 011110 (2009)CrossRefGoogle Scholar
  137. 137.
    J.H. Lee et al., Enhanced extraction efficiency of In GaN-based light-emitting diodes using 100-kHz femtosecond-laser-scribing technology. IEEE Electron Device Lett. 31(3), 213–215 (2010)CrossRefGoogle Scholar
  138. 138.
    Y.Y. Zhang et al., Light extraction efficiency improvement by multiple laser stealth dicing in In GaN-based blue light-emitting diodes. Opt. Express 20(6), 6808–6815 (2012)CrossRefGoogle Scholar
  139. 139.
    K.H. Lee et al., Light-extraction efficiency control in AlGaN-based deep-ultraviolet flip-chip light-emitting diodes: A comparison to In GaN-based visible flip-chip light-emitting diodes. Opt. Express 23(16), 20340–20349 (2015)CrossRefGoogle Scholar
  140. 140.
    Y. Guo et al., Light extraction enhancement of AlGaN-based ultraviolet light-emitting diodes by substrate sidewall roughening. Appl. Phys. Lett. 111(1), 011102 (2017)CrossRefGoogle Scholar
  141. 141.
    M.R. Krames et al., High-power truncated-inverted-pyramid (AlxGa1−x)0.5In0.5P/GaP light-emitting diodes exhibiting >50% external quantum efficiency. Appl. Phys. Lett. 75(16), 2365 (1999)CrossRefGoogle Scholar
  142. 142.
    C.E. Lee et al., Luminance enhancement of flip-chip light-emitting diodes by geometric sapphire shaping structure. IEEE Photon. Technol. Lett. 20(1–4), 184–186 (2008)CrossRefGoogle Scholar
  143. 143.
    X.H. Wang, P.T. Lai, H.W. Choi, Laser micromachining of optical microstructures with inclined sidewall profile. J. Vac. Sci. Technol. B Microelectron. Nanometer Struct. 27(3), 1048 (2009)CrossRefGoogle Scholar
  144. 144.
    B. Sun et al., Shape designing for light extraction enhancement bulk-GaN light-emitting diodes. J. Appl. Phys. 113(24), 243104 (2013)CrossRefGoogle Scholar
  145. 145.
    S.-J. Chang et al., GaN-based light-emitting diodes prepared with shifted laser stealth dicing. J. Disp. Technol. 12(2), 1 (2015)CrossRefGoogle Scholar
  146. 146.
    Y. Guo et al., Sapphire substrate sidewall shaping of deep ultraviolet light-emitting diodes by picosecond laser multiple scribing. Appl. Phys. Express 10(6), 062101 (2017)CrossRefGoogle Scholar
  147. 147.
    N. Maeda, H. Hirayama, Realization of high-efficiency deep-UV LEDs using transparent p-AlGaN contact layer. Phys. Status Solidi C 10(11), 1521–1524 (2013)CrossRefGoogle Scholar
  148. 148.
    M. Shatalov et al., High power AlGaN ultraviolet light emitters. Semicond. Sci. Technol. 29(8), 084007 (2014)CrossRefGoogle Scholar
  149. 149.
    J.W. Lee et al., An elegant route to overcome fundamentally-limited light extraction in AlGaN deep-ultraviolet light-emitting diodes: Preferential outcoupling of strong in-plane emission. Sci. Rep. 6, 22537 (2016)CrossRefGoogle Scholar
  150. 150.
    J.W. Lee et al., Arrays of truncated cone AlGaN deep-ultraviolet light-emitting diodes facilitating efficient outcoupling of in-plane emission. ACS Photon. 3(11), 2030–2034 (2016)CrossRefGoogle Scholar
  151. 151.
    Y. Guo et al., Enhancement of light extraction on AlGaN-based deep-ultraviolet light-emitting diodes using a sidewall reflection method, in Wide Bandgap Semiconductors China (SSLChina: IFWS), 2016 13th China International Forum on Solid State Lighting: International Forum on, (IEEE, New York, 2016), pp. 127–130CrossRefGoogle Scholar

Copyright information

© Springer International Publishing AG, part of Springer Nature 2019

Authors and Affiliations

  • Jianchang Yan
    • 1
    • 2
    • 3
  • Junxi Wang
    • 1
    • 2
    • 3
  • Yuhuai Liu
    • 5
    • 6
  • Jinmin Li
    • 4
  1. 1.Institute of Semiconductors, Chinese Academy of SciencesBeijingChina
  2. 2.State Key Laboratory of Solid State LightingBeijingChina
  3. 3.Beijing Engineering Research Center for the 3rd Generation Semiconductor Materials and ApplicationBeijingChina
  4. 4.Chinese Academy of SciencesState Key Laboratory of Solid State Lighting, Solid State Lighting R&D CenterBeijingChina
  5. 5.Zhengzhou UniversityZhengzhouChina
  6. 6.Nagoya UniversityNagoyaJapan

Personalised recommendations