Advertisement

Enhancing Wall-Plug Efficiency for Deep-UV Light-Emitting Diodes: From Crystal Growth to Devices

  • SM IslamEmail author
  • Vladimir Protasenko
  • Shyam Bharadwaj
  • Jai Verma
  • Kevin Lee
  • Huili (Grace) Xing
  • Debdeep Jena
Part of the Solid State Lighting Technology and Application Series book series (SSLTA, volume 4)

Abstract

Deep ultraviolet light-emitting diodes (200–280 nm) have many potential applications in diagnostics, therapeutics, security, and tanning. But, the state-of-the-art LEDs suffer from low external quantum efficiency (< 20%). The external quantum efficiency is composed of internal quantum efficiency, injection efficiency, and the light extraction efficiency. These components are limited due to fundamental material and physics-based challenges. In this chapter, a set of novel heterostructure designs are presented to improve the individual efficiency components that compose the external quantum efficiency. Theoretical analysis followed by crystal growth and experimental data are presented showing enhancement of each efficiency components. Inclusion of such new design techniques will enhance the external quantum efficiency of deep-UV light emitters.

References

  1. 1.
    T. Mukai, D. Morita, S. Nakamura, High-power UV InGaN/AlGaN double-heterostructure LEDs. J. Cryst. Growth 189–190, 778–781 (1998)CrossRefGoogle Scholar
  2. 2.
    J.P. Theodore Moustakas, Gallium-Nitride (GaN) II, Vol. 57 (Academic Press, 1998)Google Scholar
  3. 3.
    Y. Taniyasu, M. Kasu, T. Makimoto, An aluminium nitride light-emitting diode with a wavelength of 210 nanometres. Nature 441(7091), 325–328 (2006)CrossRefGoogle Scholar
  4. 4.
    A. Khan, K. Balakrishnan, T. Katona, Ultraviolet light-emitting diodes based on group three nitrides. Nat. Photonics 2(2), 77–84 (2008)CrossRefGoogle Scholar
  5. 5.
    C. Pernot, M. Kim, S. Fukahori, T. Inazu, T. Fujita, Y. Nagasawa, A. Hirano, M. Ippommatsu, M. Iwaya, S. Kamiyama, I. Akasaki, H. Amano, Improved efficiency of 255–280 nm AlGaN-based light-emitting diodes. Appl. Phys. Express 3(6) (2010)CrossRefGoogle Scholar
  6. 6.
    H. Hirayama, Y. Tsukada, T. Maeda, N. Kamata, 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) (2010)CrossRefGoogle Scholar
  7. 7.
    M. Shatalov, W. Sun, A. Lunev, X. Hu, A. Dobrinsky, Y. Bilenko, J. Yang, M. Shur, R. Gaska, C. Moe, G. Garrett, M. Wraback, AlGaN deep-ultraviolet light-emitting diodes with external quantum efficiency above 10%. Appl. Phys. Express 5(8) (2012)CrossRefGoogle Scholar
  8. 8.
    F. Bernardini, V. Fiorentini, Nonlinear behavior of spontaneous and piezoelectric polarization in III-V nitride alloys. Phys. Status Solidi (a) 190(1), 65–73 (2002)CrossRefGoogle Scholar
  9. 9.
    T. Takano, T. Mino, J. Sakai, N. Noguchi, K. Tsubaki, H. Hirayama, 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) (2017)CrossRefGoogle Scholar
  10. 10.
    M. Kneissl, T. Kolbe, C. Chua, V. Kueller, N. Lobo, J. Stellmach, A. Knauer, H. Rodriguez, S. Einfeldt, Z. Yang, N.M. Johnson, M. Weyers, Advances in group III-nitride-based deep UV light-emitting diode technology. Semicond. Sci. Technol. 26(1) (2011)CrossRefGoogle Scholar
  11. 11.
    J.K. Verma, Polarization and band gap engineered III-nitride optoelectronic device structures. Doctoral Dissertation, University of Notre Dame, 2013Google Scholar
  12. 12.
    S. Karpov, ABC-model for interpretation of internal quantum efficiency and its droop in III-nitride LEDs: a review. Opt. Quant. Electron. 47(6), 1293–1303 (2015)CrossRefGoogle Scholar
  13. 13.
    J. Piprek, Efficiency droop in nitride-based light-emitting diodes. Phys. Status Solidi (a) 207(10), 2217–2225 (2010)CrossRefGoogle Scholar
  14. 14.
    M.-H. Kim, M.F. Schubert, Q. Dai, J.K. Kim, E.F. Schubert, J. Piprek, Y. Park, Origin of efficiency droop in GaN-based light-emitting diodes. Appl. Phys. Lett. 91(18) (2007)CrossRefGoogle Scholar
  15. 15.
    G. Verzellesi, D. Saguatti, M. Meneghini, F. Bertazzi, M. Goano, G. Meneghesso, E. Zanoni, Efficiency droop in InGaN/GaN blue light-emitting diodes: Physical mechanisms and remedies. J. Appl. Phys. 114(7) (2013)CrossRefGoogle Scholar
  16. 16.
    S.F. Chichibu, H. Marchand, M.S. Minsky, S. Keller, P.T. Fini, J.P. Ibbetson, S.B. Fleischer, J.S. Speck, J.E. Bowers, E. Hu, U.K. Mishra, S.P. DenBaars, T. Deguchi, T. Sota, S. Nakamura, Emission mechanisms of bulk GaN and InGaN quantum wells prepared by lateral epitaxial overgrowth. Appl. Phys. Lett. 74(10), 1460–1462 (1999)CrossRefGoogle Scholar
  17. 17.
    Q. Dai, M.F. Schubert, M.H. Kim, J.K. Kim, E.F. Schubert, D.D. Koleske, M.H. Crawford, S.R. Lee, A.J. Fischer, G. Thaler, M.A. Banas, Internal quantum efficiency and nonradiative recombination coefficient of GaInN/GaN multiple quantum wells with different dislocation densities. Appl. Phys. Lett. 94(11) (2009)Google Scholar
  18. 18.
    M. Soltani, R. Soref, T. Palacios, D. Englund, AlGaN/AlN integrated photonics platform for the ultraviolet and visible spectral range. Opt Express 24(22), 25415–25423 (2016)CrossRefGoogle Scholar
  19. 19.
    H. Hirayama, S. Fujikawa, J. Norimatsu, T. Takano, K. Tsubaki, N. Kamata, Fabrication of a low threading dislocation density ELO-AlN template for application to deep-UV LEDs. Phys. Status Solidi (c) 6(S2), S356–S359 (2009)CrossRefGoogle Scholar
  20. 20.
    M. Conroy, V.Z. Zubialevich, H. Li, N. Petkov, J.D. Holmes, P.J. Parbrook, Epitaxial lateral overgrowth of AlN on self-assembled patterned nanorods. J. Mater. Chem. C 3(2), 431–437 (2015)CrossRefGoogle Scholar
  21. 21.
    V.N. Jmerik, E.V. Lutsenko, S.V. Ivanov, Plasma-assisted molecular beam epitaxy of AlGaN heterostructures for deep-ultraviolet optically pumped lasers. Phys. Status Solidi (a) 210(3), 439–450 (2013)CrossRefGoogle Scholar
  22. 22.
    R. Dalmau, Z. Sitar, AlN bulk crystal growth by physical vapor transport, in Springer Handbook of Crystal Growth, ed. by G. Dhanaraj, K. Byrappa, V. Prasad, M. Dudley (Springer, Berlin, Heidelberg, 2010), pp. 821–843CrossRefGoogle Scholar
  23. 23.
    J.S. Speck, S.J. Rosner, The role of threading dislocations in the physical properties of GaN and its alloys. Phys. B Condens. Matter 273–274, 24–32 (1999)CrossRefGoogle Scholar
  24. 24.
    R. Collazo, J. Xie, B.E. Gaddy, Z. Bryan, R. Kirste, M. Hoffmann, R. Dalmau, B. Moody, Y. Kumagai, T. Nagashima, Y. Kubota, T. Kinoshita, A. Koukitu, D.L. Irving, Z. Sitar, On the origin of the 265 nm absorption band in AlN bulk crystals. Appl. Phys. Lett. 100(19) (2012)CrossRefGoogle Scholar
  25. 25.
    R. Dalmau, B. Moody, R. Schlesser, S. Mita, J. Xie, M. Feneberg, B. Neuschl, K. Thonke, R. Collazo, A. Rice, J. Tweedie, Z. Sitar, Growth and characterization of AlN and AlGaN epitaxial films on AlN single crystal substrates. J. Electrochem. Soc. 158(5) (2011)Google Scholar
  26. 26.
    K. Zhu, M.L. Nakarmi, K.H. Kim, J.Y. Lin, H.X. Jiang, Silicon doping dependence of highly conductive n-type Al0.7Ga0.3N. Appl. Phys. Lett. 85(20), 4669–4671 (2004)CrossRefGoogle Scholar
  27. 27.
    R. France, T. Xu, P. Chen, R. Chandrasekaran, T.D. Moustakas, Vanadium-based Ohmic contacts to n-AlGaN in the entire alloy composition. Appl. Phys. Lett. 90(6) (2007)CrossRefGoogle Scholar
  28. 28.
    J.P. Zhang, A. Chitnis, V. Adivarahan, S. Wu, V. Mandavilli, R. Pachipulusu, M. Shatalov, G. Simin, J.W. Yang, M.A. Khan, Milliwatt power deep ultraviolet light-emitting diodes over sapphire with emission at 278 nm. Appl. Phys. Lett. 81(26), 4910–4912 (2002)CrossRefGoogle Scholar
  29. 29.
    M.L. Nakarmi, K.H. Kim, M. Khizar, Z.Y. Fan, J.Y. Lin, H.X. Jiang, Electrical and optical properties of Mg-doped Al0.7Ga0.3N alloys. Appl. Phys. Lett. 86(9) (2005)CrossRefGoogle Scholar
  30. 30.
    Y. Bilenko, A. Lunev, X. Hu, J. Deng, T.M. Katona, J. Zhang, R. Gaska, M.S. Shur, W. Sun, V. Adivarahan, M. Shatalov, A. Khan, 10 Milliwatt pulse operation of 265 nm AlGaN light emitting diodes. Jpn. J. Appl. Phys. 44(3), L98–L100 (2005)CrossRefGoogle Scholar
  31. 31.
    H. Yu, E. Ulker, E. Ozbay, MOCVD growth and electrical studies of p-type AlGaN with Al fraction 0.35. J. Cryst. Growth 289(2), 419–422 (2006)CrossRefGoogle Scholar
  32. 32.
    T. Kinoshita, T. Obata, H. Yanagi, S.-i. Inoue, High p-type conduction in high-Al content Mg-doped AlGaN. Appl. Phys. Lett. 102(1) (2013)CrossRefGoogle Scholar
  33. 33.
    T. Mori, K. Nagamatsu, K. Nonaka, K. Takeda, M. Iwaya, S. Kamiyama, H. Amano, I. Akasaki, Crystal growth and p-type conductivity control of AlGaN for high-efficiency nitride-based UV emitters. Phys. Status Solidi (c) 6(12), 2621–2625 (2009)CrossRefGoogle Scholar
  34. 34.
    K.P. Streubel, T. Passow, H. Jeon, R. Gutt, M. Maier, L.-W. Tu, N. Linder, W. Pletschen, M. Kunzer, R. Schmidt, J. Wiegert, D. Luick, S. Liu, K. Köhler, J. Wagner, Ni/Ag as low resistive ohmic contact to p-type AlGaN for UV LEDs, in Light-Emitting Diodes: Materials, Devices, and Applications for Solid State Lighting XIV, 2010Google Scholar
  35. 35.
    B.A. Hull, S.E. Mohney, U. Chowdhury, R.D. Dupuis, Ohmic contacts to p-type Al0.45Ga0.55N. J. Appl. Phys. 96(12), 7325–7331 (2004)CrossRefGoogle Scholar
  36. 36.
    H.-K. Kim, T.-Y. Seong, I. Adesida, C.W. Tang, K.M. Lau, Low-resistance Pt/Pd/Au ohmic contacts to p-type AlGaN. Appl. Phys. Lett. 84(10), 1710–1712 (2004)CrossRefGoogle Scholar
  37. 37.
    M. Shatalov, W. Sun, R. Jain, A. Lunev, X. Hu, A. Dobrinsky, Y. Bilenko, J. Yang, G.A. Garrett, L.E. Rodak, M. Wraback, M. Shur, R. Gaska, High power AlGaN ultraviolet light emitters. Semicond. Sci. Technol. 29(8) (2014)CrossRefGoogle Scholar
  38. 38.
    J. Simon, V. Protasenko, C. Lian, H. Xing, D. Jena, Polarization-induced hole doping in wide-band-gap uniaxial semiconductor heterostructures. Science 327(5961), 60–64 (2010)CrossRefGoogle Scholar
  39. 39.
    J. Verma, P.K. Kandaswamy, V. Protasenko, A. Verma, H. Grace Xing, D. Jena, Tunnel-injection GaN quantum dot ultraviolet light-emitting diodes. Appl. Phys. Lett. 102(4) (2013)CrossRefGoogle Scholar
  40. 40.
    Y. Zhang, A.A. Allerman, S. Krishnamoorthy, F. Akyol, M.W. Moseley, A.M. Armstrong, S. Rajan, Enhanced light extraction in tunnel junction-enabled top emitting UV LEDs. Appl. Phys. Express 9(5) (2016)CrossRefGoogle Scholar
  41. 41.
    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
  42. 42.
    M.R. Krames, M. Ochiai-Holcomb, G.E. Höfler, C. Carter-Coman, E.I. Chen, I.H. Tan, P. Grillot, N.F. Gardner, H.C. Chui, J.W. Huang, S.A. Stockman, F.A. Kish, M.G. Craford, T.S. Tan, C.P. Kocot, M. Hueschen, J. Posselt, B. Loh, G. Sasser, D. Collins, High-power truncated-inverted-pyramid (AlxGa1−x)0.5In0.5P/GaP light-emitting diodes exhibiting >50% external quantum efficiency. Appl. Phys. Lett. 75(16), 2365–2367 (1999)Google Scholar
  43. 43.
    T. Kolbe, F. Mehnke, M. Guttmann, C. Kuhn, J. Rass, T. Wernicke, M. Kneissl, Improved injection efficiency in 290 nm light emitting diodes with Al(Ga)N electron blocking heterostructure. Appl. Phys. Lett. 103(3) (2013)CrossRefGoogle Scholar
  44. 44.
    Z. Ren, Q. Sun, S.Y. Kwon, J. Han, K. Davitt, Y.K. Song, A.V. Nurmikko, H.K. Cho, W. Liu, J.A. Smart, L.J. Schowalter, Heteroepitaxy of AlGaN on bulk AlN substrates for deep ultraviolet light emitting diodes. Appl. Phys. Lett. 91(5) (2007)CrossRefGoogle Scholar
  45. 45.
    M. Jo, N. Maeda, H. Hirayama, Enhanced light extraction in 260 nm light-emitting diode with a highly transparent p-AlGaN layer. Appl. Phys. Express 9(1) (2016)CrossRefGoogle Scholar
  46. 46.
    J. Verma, S.M. Islam, V. Protasenko, P. Kumar Kandaswamy, H. Xing, D. Jena, Tunnel-injection quantum dot deep-ultraviolet light-emitting diodes with polarization-induced doping in III-nitride heterostructures. Appl. Phys. Lett. 104(2) (2014)CrossRefGoogle Scholar
  47. 47.
    S.M. Islam, K. Lee, J. Verma, V. Protasenko, S. Rouvimov, S. Bharadwaj, H. Xing, D. Jena, MBE-grown 232–270 nm deep-UV LEDs using monolayer thin binary GaN/AlN quantum heterostructures. Appl. Phys. Lett. 110(4) (2017)CrossRefGoogle Scholar
  48. 48.
    J. Zhang, H. Zhao, N. Tansu, Effect of crystal-field split-off hole and heavy-hole bands crossover on gain characteristics of high Al-content AlGaN quantum well lasers. Appl. Phys. Lett. 97(11) (2010)CrossRefGoogle Scholar
  49. 49.
    T. Kolbe, A. Knauer, C. Chua, Z. Yang, S. Einfeldt, P. Vogt, N.M. Johnson, M. Weyers, M. Kneissl, Optical polarization characteristics of ultraviolet (In)(Al)GaN multiple quantum well light emitting diodes. Appl. Phys. Lett. 97(17) (2010)CrossRefGoogle Scholar
  50. 50.
    X.-H. Li, T.-T. Kao, M.M. Satter, Y.O. Wei, S. Wang, H. Xie, S.-C. Shen, P.D. Yoder, A.M. Fischer, F.A. Ponce, T. Detchprohm, R.D. Dupuis, Demonstration of transverse-magnetic deep-ultraviolet stimulated emission from AlGaN multiple-quantum-well lasers grown on a sapphire substrate. Appl. Phys. Lett. 106(4) (2015)CrossRefGoogle Scholar
  51. 51.
    C. Reich, M. Guttmann, M. Feneberg, T. Wernicke, F. Mehnke, C. Kuhn, J. Rass, M. Lapeyrade, S. Einfeldt, A. Knauer, V. Kueller, M. Weyers, R. Goldhahn, M. Kneissl, Strongly transverse-electric-polarized emission from deep ultraviolet AlGaN quantum well light emitting diodes. Appl. Phys. Lett. 107(14) (2015)CrossRefGoogle Scholar
  52. 52.
    J.E. Northrup, C.L. Chua, Z. Yang, T. Wunderer, M. Kneissl, N.M. Johnson, T. Kolbe, Effect of strain and barrier composition on the polarization of light emission from AlGaN/AlN quantum wells. Appl. Phys. Lett. 100(2) (2012)CrossRefGoogle Scholar
  53. 53.
    D.A.B. Miller, D.S. Chemla, T.C. Damen, A.C. Gossard, W. Wiegmann, T.H. Wood, C.A. Burrus, Band-edge electroabsorption in quantum well structures: the quantum-confined Stark effect. Phys. Rev. Lett. 53(22), 2173–2176 (1984)CrossRefGoogle Scholar
  54. 54.
    T. Tetsuya, S. Shigetoshi, K. Maki, K. Miho, T. Hideo, A. Hiroshi, A. Isamu, Quantum-confined Stark effect due to piezoelectric fields in GaInN strained quantum wells. Jpn. J. Appl. Phys. 36(4A), L382 (1997)CrossRefGoogle Scholar
  55. 55.
    J. Zhang, H. Zhao, N. Tansu, Large optical gain AlGaN-delta-GaN quantum wells laser active regions in mid- and deep-ultraviolet spectral regimes. Appl. Phys. Lett. 98(17) (2011)CrossRefGoogle Scholar
  56. 56.
    D. Bayerl, S.M. Islam, C.M. Jones, V. Protasenko, D. Jena, E. Kioupakis, Deep ultraviolet emission from ultra-thin GaN/AlN heterostructures. Appl. Phys. Lett. 109(24) (2016)CrossRefGoogle Scholar
  57. 57.
    J. Selles, C. Brimont, G. Cassabois, P. Valvin, T. Guillet, I. Roland, Y. Zeng, X. Checoury, P. Boucaud, M. Mexis, F. Semond, B. Gayral, Deep-UV nitride-on-silicon microdisk lasers. Sci. Rep. 6(21650) (2016)Google Scholar
  58. 58.
    E. Kioupakis, Q. Yan, C.G. Van de Walle, Interplay of polarization fields and Auger recombination in the efficiency droop of nitride light-emitting diodes. Appl. Phys. Lett. 101(23) (2012)CrossRefGoogle Scholar
  59. 59.
    J.M. Rondinelli, E. Kioupakis, Predicting and designing optical properties of inorganic materials. Annu. Rev. Mater. Res. 45(1), 491–518 (2015)CrossRefGoogle Scholar
  60. 60.
    J.A. Ferrer-Pérez, B. Claflin, D. Jena, M. Sen, R. Vetury, D. Dorsey, Photoluminescence-based electron and lattice temperature measurements in GaN-based HEMTs. J. Electron. Mater. 43(2), 341–347 (2014)CrossRefGoogle Scholar
  61. 61.
    R. Bhattacharya, B. Pal, B. Bansal, On conversion of luminescence into absorption and the van Roosbroeck-Shockley relation. Appl. Phys. Lett. 100(22) (2012)CrossRefGoogle Scholar
  62. 62.
    L.K. Lee, L. Zhang, H. Deng, P.C. Ku, Room-temperature quantum-dot-like luminescence from site-controlled InGaN quantum disks. Appl. Phys. Lett. 99(26) (2011)CrossRefGoogle Scholar
  63. 63.
    S.M. Islam, V. Protasenko, S. Rouvimov, H. Xing, D. Jena, Sub-230 nm deep-UV emission from GaN quantum disks in AlN grown by a modified Stranski–Krastanov mode. Jpn. J. Appl. Phys. 55(5S) (2016)CrossRefGoogle Scholar
  64. 64.
    C.T. Foxon, C.S. Davis, S.V. Novikov, O.H. Hughes, T.S. Cheng, D. Korakakis, N.J. Jeffs, I. Grzegory, S. Porowski, RHEED studies of group III-Nitrides grown by MBE. Phys. Status Solidi (a) 176(1), 723–726 (1999)CrossRefGoogle Scholar
  65. 65.
    N. Gogneau, D. Jalabert, E. Monroy, E. Sarigiannidou, J.L. Rouvière, T. Shibata, M. Tanaka, J.M. Gerard, B. Daudin, Influence of AlN overgrowth on structural properties of GaN quantum wells and quantum dots grown by plasma-assisted molecular beam epitaxy. J. Appl. Phys. 96(2), 1104–1110 (2004)CrossRefGoogle Scholar
  66. 66.
    D. Doppalapudi, E. Iliopoulos, S.N. Basu, T.D. Moustakas, Epitaxial growth of gallium nitride thin films on A-Plane sapphire by molecular beam epitaxy. J. Appl. Phys. 85(7), 3582–3589 (1999)CrossRefGoogle Scholar
  67. 67.
    Y. Horikoshi, Migration-enhanced epitaxy of GaAs and AlGaAs. Semicond. Sci. Technol. 8(6), 1032 (1993)CrossRefGoogle Scholar
  68. 68.
    C. Adelmann, B. Daudin, R.A. Oliver, G.A.D. Briggs, R.E. Rudd, Nucleation and growth of GaN/AlN quantum dots. Phys. Rev. B 70(12) (2004)Google Scholar
  69. 69.
    B. Daudin, F. Widmann, G. Feuillet, Y. Samson, M. Arlery, J.L. Rouvière, Stranski-Krastanov growth mode during the molecular beam epitaxy of highly strained GaN. Phys. Rev. B 56(12), R7069–R7072 (1997)CrossRefGoogle Scholar
  70. 70.
    Y. Taniyasu, M. Kasu, Polarization property of deep-ultraviolet light emission from C-plane AlN/GaN short-period superlattices. Appl. Phys. Lett. 99(25) (2011)CrossRefGoogle Scholar
  71. 71.
    K. Kamiya, Y. Ebihara, K. Shiraishi, M. Kasu, Structural design of AlN/GaN superlattices for deep-ultraviolet light-emitting diodes with high emission efficiency. Appl. Phys. Lett. 99(15) (2011)CrossRefGoogle Scholar
  72. 72.
    Z. Zheng, H. Ji, P. Yu, Z. Wang, Recent progress towards quantum dot solar cells with enhanced optical absorption. Nanoscale Res. Lett. 11(1), 266 (2016)Google Scholar
  73. 73.
    Y.-K. Kuo, T.-H. Wang, J.-Y. Chang, Advantages of blue InGaN light-emitting diodes with InGaN-AlGaN-InGaN barriers. Appl. Phys. Lett. 100(3) (2012)CrossRefGoogle Scholar
  74. 74.
    T. Passow, K. Leonardi, A. Stockmann, H. Selke, H. Heinke, D. Hommel, High-resolution x-ray diffraction investigations of highly mismatched II-VI quantum wells. J. Phys. D Appl. Phys. 32(10A), A42 (1999)CrossRefGoogle Scholar
  75. 75.
    S. Islam, V. Protasenko, S. Rouvimov, J. Verma, H. Xing, D. Jena, Deep-UV LEDs using polarization-induced doping: Electroluminescence at cryogenic temperatures, in 2015 73rd Annual Device Research Conference (DRC), 21–24 June 2015; 2015; pp 67–68Google Scholar
  76. 76.
    J. Simon, Y. Cao, D. Jena, Short-period AlN/GaN p-type superlattices: hole transport use in p-n junctions. Phys. Status Solidi (c) 7(10), 2386–2389 (2010)CrossRefGoogle Scholar
  77. 77.
    D. Jena, S. Heikman, D. Green, D. Buttari, R. Coffie, H. Xing, S. Keller, S. DenBaars, J.S. Speck, U.K. Mishra, I. Smorchkova, Realization of wide electron slabs by polarization bulk doping in graded III–V nitride semiconductor alloys. Appl. Phys. Lett. 81(23), 4395–4397 (2002)CrossRefGoogle Scholar
  78. 78.
    J. Yan, J. Wang, P. Cong, L. Sun, N. Liu, Z. Liu, C. Zhao, J. Li, Improved performance of UV-LED by p-AlGaN with graded composition. Phys. Status Solidi (c) 8(2), 461–463 (2011)CrossRefGoogle Scholar
  79. 79.
    S. Li, M.E. Ware, V.P. Kunets, M. Hawkridge, P. Minor, J. Wu, G.J. Salamo, Polarization induced doping in graded AlGaN films. Phys. Status Solidi (c) 8(7–8), 2182–2184 (2011)CrossRefGoogle Scholar
  80. 80.
    S.D. Carnevale, T.F. Kent, P.J. Phillips, M.J. Mills, S. Rajan, R.C. Myers, Polarization-induced pn diodes in wide-band-gap nanowires with ultraviolet electroluminescence. Nano Lett. 12(2), 915–20 (2012)CrossRefGoogle Scholar
  81. 81.
    L. Zhang, X.C. Wei, N.X. Liu, H.X. Lu, J.P. Zeng, J.X. Wang, Y.P. Zeng, J.M. Li, Improvement of efficiency of GaN-based polarization-doped light-emitting diodes grown by metalorganic chemical vapor deposition. Appl. Phys. Lett. 98(24) (2011)CrossRefGoogle Scholar
  82. 82.
    A. Yasan, R. McClintock, K. Mayes, S.R. Darvish, P. Kung, M. Razeghi, Top-emission ultraviolet light-emitting diodes with peak emission at 280 nm. Appl. Phys. Lett. 81(5), 801–802 (2002)CrossRefGoogle Scholar
  83. 83.
    A. Yasan, R. McClintock, K. Mayes, D.H. Kim, P. Kung, M. Razeghi, Photoluminescence study of AlGaN-based 280 nm ultraviolet light-emitting diodes. Appl. Phys. Lett. 83(20), 4083–4085 (2003)CrossRefGoogle Scholar
  84. 84.
    A. Chitnis, V. Adivarahan, M. Shatalov, J. Zhang, M. Gaevski, W. Shuai, R. Pachipulusu, J. Sun, K. Simin, G. Simin, J. Yang, M.A. Khan, Submilliwatt operation of AlInGaN based multifinger-design 315 nm Light Emitting Diode (LED) over sapphire substrate. Jpn. J. Appl. Phys. 41(Part 2, No. 3B), L320–L322 (2002)CrossRefGoogle Scholar
  85. 85.
    B. Cheng, S. Choi, J.E. Northrup, Z. Yang, C. Knollenberg, M. Teepe, T. Wunderer, C.L. Chua, N.M. Johnson, Enhanced vertical and lateral hole transport in high aluminum-containing AlGaN for deep ultraviolet light emitters. Appl. Phys. Lett. 102(23) (2013)CrossRefGoogle Scholar
  86. 86.
    F.A.F. Jimy Encomendero, S.M. Islam, V. Protasenko, S. Rouvimov, P. Fay, D. Jena, H.G. Xing, Repeatable room temperature negative differential conductance in GaN/AlN resonant tunneling diodes. arXiv:1606.08100 [cond-mat.mes-hall] (2016)Google Scholar
  87. 87.
    C. Liu, Y.K. Ooi, S.M. Islam, J. Verma, H. Xing, D. Jena, J. Zhang, Physics and polarization characteristics of 298 nm AlN-delta-GaN quantum well ultraviolet light-emitting diodes. Appl. Phys. Lett. 110(7), 071103 (2017)CrossRefGoogle Scholar

Copyright information

© Springer International Publishing AG, part of Springer Nature 2019

Authors and Affiliations

  • SM Islam
    • 1
    Email author
  • Vladimir Protasenko
    • 1
  • Shyam Bharadwaj
    • 1
  • Jai Verma
    • 2
  • Kevin Lee
    • 1
  • Huili (Grace) Xing
    • 1
  • Debdeep Jena
    • 1
  1. 1.Cornell UniversityIthacaUSA
  2. 2.University of Notre DameNotre DameUSA

Personalised recommendations