Enhanced light emission of nano-patterned GaN via block copolymer thin films

Yo-Han Cho; Kyunghee Lee; Kyunghoon Kim; Kwang Hyun Baik; Jinhan Cho; Jihyun Kim; Kyusoon Shin; Joona Bang

Korean Journal of Chemical Engineering, Vol.26, No.1, 277-280, January, 2009

DOI10.1007/s11814-009-0047-4 Export Citation

Enhanced light emission of nano-patterned GaN via block copolymer thin films

Yo-Han Cho, Kyunghee Lee, Kyunghoon Kim, Kwang Hyun Baik¹, Jinhan Cho², Jihyun Kim³, Kyusoon Shin^†, and Joona Bang^{3, †}

School of Chemical and Biological Engineering, Seoul National University, Seoul 151-744, Korea
¹Samsung Advanced Institute of Technology, Yongin-si, Gyeonggi-do 446-712, Korea
²School of Advanced Materials Engineering, Kookmin University, Seoul 136-70, Korea
³Department of Chemical and Biological Engineering, Korea University, Seoul 136-713, Korea

E-mail:,

Abstract.We demonstrate that the nanoscopic block copolymer patterns on GaN can enhance light extraction efficiency of GaN-based light emitting diodes. Nanoporous patterns were fabricated on a bare GaN substrate via self-assembly of poly(styrene-b-methyl methacrylate) block copolymers from which PMMA microdomains were selectively removed later on. A bare GaN surface was treated with a photo-crosslinkable thin layer of poly(styrene-r-methyl methacrylate) random copolymers to tune the cylindrical microdomain orientations. The nanoporous block copolymer thin film was controlled to be thicker than its typical repeat period in bulk by incorporating PMMA homopolymer into block copolymer. Consequently, the light extraction efficiency in photoluminescence spectra could be tuned with the thickness of nanopatterned thin film on GaN.

Keywords:GaN;Light Emitting Diodes;Block Copolymers;Nanoporous Templates

[References]

Shur MS, Davis RE, GaN-based materials and devices, World Scientific, Singapore (2004)
Razeghi M, Henini M, Optoelectronic devices, Elsevier B. V., Amsterdam (2004)
Morkoc H, Nitride semiconductors and devices, Springer, Heidelberg (1999)
Fujii T, David A, Gao Y, Iza M, Denbaars SP, Hu EL, Weisbuch C, Nakamura S, Phys. Stat. Sol., 2, 2836 (2005)
Fujii T, Gao Y, Sharma R, Hu EL, Denbaars SP, Nakamura S, Appl. Phys. Lett., 84, 855 (2004)
Kim DH, Cho CO, Roh YG, Jeon H, Park YS, Cho J, Lim JS, Sone C, Park Y, Choi WJ, Park QH, Appl. Phys. Lett., 87, 203508 (2005)
Kim K, Choi J, Bae TS, Appl. Phys. Lett., 90, 18192 (2007)
Park M, Harrison C, Chaikin PM, Register RA, Adamson DH, Science, 276(5317), 1401 (1997)
Black CT, Guarini KW, Milkove KR, Baker SM, Russell TR, Tuominen MT, Appl. Phys. Lett., 79, 409 (2001)
Kim HC, Jia X, Stafford CM, Kim DH, McCarthy TJ, Tuominen M, Hawker CJ, Russell TP, Adv. Mater., 19, 795 (2001)
Shin K, Leach KA, Goldbach JT, Kim DH, Jho JY, Tuominen M, Hawker CJ, Russell TP, Nano. Lett., 2, 933 (2002)
Huang E, Pruzinsky S, Russell TP, Mays J, Hawker CJ, Macromolecules, 32(16), 5299 (1999)
Mansky P, Liu Y, Huang E, Russell TP, Hawker C, Science, 275(5305), 1458 (1997)
Bang J, Bae J, Lowenhielm P, Spiessberger C, Given-Beck SA, Russell TP, Hawker CJ, Adv. Mater., 19, 4552 (2007)
Thurn-Albrecht T, Schotter J, Kastle GA, Emley N, Shibauchi T, Krusin-Elbaum L, Guarini K, Black CT, Tuominen MT, Russell TP, Science, 290, 2126 (2000)
Kim SH, Misner MJ, Xu T, Kimura M, Russell TP, Adv. Mater., 16(3), 226 (2004)
Kim YW, Kim JJ, Kim YH, Korean J. Chem. Eng., 20(6), 1158 (2003)
Won YY, Korean J. Chem. Eng., 21(1), 296 (2004)
Gombert A, Glaubitt W, Rose K, Dreibholz J, Blasi B, Heinzel A, Sporn D, Doll W, Wittwer V, Thin Solid Films, 351(1-2), 73 (1999)
Jeong U, Ryu DY, Kho DH, Kim JK, Goldbach JT, Kim DH, Russell TP, Adv. Mater., 16(6), 533 (2004)

[Related Articles]

[1] Shur MS, Davis RE, GaN-based materials and devices, World Scientific, Singapore (2004)

[2] Razeghi M, Henini M, Optoelectronic devices, Elsevier B. V., Amsterdam (2004)

[3] Morkoc H, Nitride semiconductors and devices, Springer, Heidelberg (1999)

[4] Fujii T, David A, Gao Y, Iza M, Denbaars SP, Hu EL, Weisbuch C, Nakamura S, Phys. Stat. Sol., 2, 2836 (2005)

[5] Fujii T, Gao Y, Sharma R, Hu EL, Denbaars SP, Nakamura S, Appl. Phys. Lett., 84, 855 (2004)

[6] Kim DH, Cho CO, Roh YG, Jeon H, Park YS, Cho J, Lim JS, Sone C, Park Y, Choi WJ, Park QH, Appl. Phys. Lett., 87, 203508 (2005)

[7] Kim K, Choi J, Bae TS, Appl. Phys. Lett., 90, 18192 (2007)

[8] Park M, Harrison C, Chaikin PM, Register RA, Adamson DH, Science, 276(5317), 1401 (1997)

[9] Black CT, Guarini KW, Milkove KR, Baker SM, Russell TR, Tuominen MT, Appl. Phys. Lett., 79, 409 (2001)

[10] Kim HC, Jia X, Stafford CM, Kim DH, McCarthy TJ, Tuominen M, Hawker CJ, Russell TP, Adv. Mater., 19, 795 (2001)

[11] Shin K, Leach KA, Goldbach JT, Kim DH, Jho JY, Tuominen M, Hawker CJ, Russell TP, Nano. Lett., 2, 933 (2002)

[12] Huang E, Pruzinsky S, Russell TP, Mays J, Hawker CJ, Macromolecules, 32(16), 5299 (1999)

[13] Mansky P, Liu Y, Huang E, Russell TP, Hawker C, Science, 275(5305), 1458 (1997)

[14] Bang J, Bae J, Lowenhielm P, Spiessberger C, Given-Beck SA, Russell TP, Hawker CJ, Adv. Mater., 19, 4552 (2007)

[15] Thurn-Albrecht T, Schotter J, Kastle GA, Emley N, Shibauchi T, Krusin-Elbaum L, Guarini K, Black CT, Tuominen MT, Russell TP, Science, 290, 2126 (2000)

[16] Kim SH, Misner MJ, Xu T, Kimura M, Russell TP, Adv. Mater., 16(3), 226 (2004)

[17] Kim YW, Kim JJ, Kim YH, Korean J. Chem. Eng., 20(6), 1158 (2003)

[18] Won YY, Korean J. Chem. Eng., 21(1), 296 (2004)

[19] Gombert A, Glaubitt W, Rose K, Dreibholz J, Blasi B, Heinzel A, Sporn D, Doll W, Wittwer V, Thin Solid Films, 351(1-2), 73 (1999)

[20] Jeong U, Ryu DY, Kho DH, Kim JK, Goldbach JT, Kim DH, Russell TP, Adv. Mater., 16(6), 533 (2004)