Effect of Oxygen Annealing on the Surface Defects and Photoconductivity of Vertically Aligned ZnO Nanowire Array
Post growth annealing of solution grown ZnO
nanowire array is performed under controlled oxygen ambience. The
role of annealing over surface defects and their consequence on
dark/photo-conductivity and photosensitivity of nanowire array is
investigated. Surface defect properties are explored using various
measurement tools such as contact angle, photoluminescence, Raman
spectroscopy and XPS measurements. The contact angle of the NW
films reduces due to oxygen annealing and nanowire film surface
changes from hydrophobic (96°) to hydrophilic (16°). Raman and
XPS spectroscopy reveal that oxygen annealing improves the crystal
quality of the nanowire films. The defect band emission intensity
(relative to band edge emission, ID/IUV) reduces from 1.3 to 0.2 after
annealing at 600 °C at 10 SCCM flow of oxygen. An order
enhancement in dark conductivity is observed in O2 annealed
samples, while photoconductivity is found to be slightly reduced due
to lower concentration of surface related oxygen defects.
[1] J. Bao, M. Zimmler, F. Capasso, X. Wang, and Z. F. Ren, "Broadband
ZnO single-nanowire light-emitting diode.," Nano letters, vol. 6, no. 8,
pp. 1719, 2006.
[2] A. I. Hochbaum and P. Yang, "Semiconductor nanowires for energy
conversion," Chemical reviews, vol. 110, no. 1, pp. 527, 2010.
[3] Q. Wan, Q. H. Li, Y. J. Chen, T. H. Wang, X. L. He, J. P. Li, and C. L.
Lin, "Fabrication and ethanol sensing characteristics of ZnO nanowire
gas sensors," Applied Physics Letters, vol. 84, no. 18, p. 3654, 2004.
[4] V. S. Sundaram and A. Mizel, "Surface effects on nanowire transport: a
numerical investigation using the Boltzmann equation," Journal of
Physics: Condensed Matter, vol. 16, no. 26, pp. 4697, 2004.
[5] U. Ozgur, Y. I. Alivov, C. Liu, M. Reshchikov, S. Dogan, V. Avrutin,
S.-J. Cho, and H. Morkoc, "A comprehensive review of ZnO materials
and devices," Journal of Applied Physics, vol. 98, no. 4, p. 041301,
2005.
[6] A. B. Djurisić and Y. H. Leung, "Optical properties of ZnO
nanostructures.," Small, vol. 2, no. 8-9, pp. 944, 2006.
[7] K. Vanheusden, W. L. Warren, C. H. Seager, D. R. Tallant, J. a. Voigt,
and B. E. Gnade, "Mechanisms behind green photoluminescence in ZnO
phosphor powders," Journal of Applied Physics, vol. 79, no. 10, p. 7983,
1996.
[8] S. A. Studenikin "Fabrication of green and orange photoluminescent,
undoped ZnO films using spray pyrolysis" Journal of Applied Physics,
Vol. 84, No. 4, pp. 2287, 1998.
[9] F. H. Leiter, H. R. Alves, A. Hofstaetter, D. M. Hofmann, B. K. Meyer,
and I. P. Institut, "The Oxygen Vacancy as the Origin of a Green
Emission in Undoped ZnO," phys. stat. sol. (b) 226, No. 1, R4-R5,
2001.
[10] B. Panigrahy, M. Aslam, D. S. Misra, M. Ghosh, and D. Bahadur,
"Defect-Related Emissions and Magnetization Properties of ZnO
Nanorods," Advanced Functional Materials, vol. 20, no. 7, pp. 1161,
2010.
[11] Y. Sato, H. Kusumi, H. Yamaguchi, T. Komiyama, and T. Aoyama,
"Photoconductive properties of ZnO crystals with post-growth
annealing," Physica B: Condensed Matter, vol. 376, no. 377, pp. 719,
2006.
[12] M. Rusop, "Post-growth annealing of zinc oxide thin films pulsed laser
deposited under enhanced oxygen pressure on quartz and silicon
substrates" Materials Science and Engineering: B, vol. 127, pp. 150,
2006.
[13] Q. Zhao, X. Y. Xu, X. F. Song, X. Z. Zhang, D. P. Yu, C. P. Li, and L.
Guo, "Enhanced field emission from ZnO nanorods via thermal
annealing in oxygen," Applied Physics Letters, vol. 88, no. 3, p. 033102,
2006.
[14] H. S. Kang, "Annealing effect on the property of ultraviolet and green
emissions of ZnO thin films," Journal of Applied Physics, vol. 95, no. 3,
p. 1246, 2004.
[15] Q. Xu, R. Hong, H. Huang, Z. Zhang, M. Zhang, X. Chen, and Z.
.Wu, "Laser annealing effect on optical and electrical properties of Al
doped ZnO films," Optics & Laser Technology, vol. 45, pp. 513, 2013.
[16] A. Kushwaha and M. Aslam, "Controlled growth of highly oriented ZnO
nanorod array on amorphous glass substrate and their optical and
electrical properties," International Journal of Nanoscience, vol. 10, no.
4-5, p. 635, 2011.
[17] S. Wang, Y. Song, and L. Jiang, "Photoresponsive surfaces with
controllable wettability," Journal of Photochemistry and Photobiology
C: Photochemistry Reviews, vol. 8, no. 1, pp. 18, 2007.
[18] N. Verplanck, Y. Coffinier, V. Thomy, and R. Boukherroub,
"Wettability Switching Techniques on Superhydrophobic Surfaces,"
Nanoscale Research Letters, vol. 2, no. 12, pp. 577, 2007.
[19] S. Patra, S. Sarkar, S. K. Bera, G. K. Paul, and R. Ghosh, "Influence of
surface topography and chemical structure on wettability of
electrodeposited ZnO thin films," Journal of Applied Physics, vol. 108,
no. 8, p. 083507, 2010.
[20] M. Sun, Y. Du, W. Hao, H. Xu, Y. Yu, and T. Wang, "Fabrication and
Wettability of ZnO Nanorod Array," J. Mater. Sci. Technol vol. 25, no.
1, pp. 53, 2009.
[21] V. R. Shinde, C. D. Lokhande, R. S. Mane, and S.-H. Han,
"Hydrophobic and textured ZnO films deposited by chemical bath
deposition: annealing effect," Applied Surface Science, vol. 245, no. 1-
4, pp. 407, 2005.
[22] R. Sun, A. Nakajima, A. Fujishima, T. Watanabe, and K. Hashimoto,
"Photoinduced Surface Wettability Conversion of ZnO and TiO 2 Thin
Films," J Phys. Chem. B, vol. 105, no. 4, pp. 1984, 2001.
[23] A. C. Gandhi, H.-J. Hung, P.-H. Shih, C.-L. Cheng, Y.-R. Ma, and S.
Wu, "In Situ Confocal Raman Mapping Study of a Single Ti-Assisted
ZnO Nanowire.," Nanoscale research letters, vol. 5, no. 3, pp. 581,
2009.
[24] K. Alim, V. Fonoberov, M. Shamsa, and A. Balandin, "Micro-Raman
investigation of optical phonons in ZnO nanocrystals," Journal of
Applied Physics, vol. 97, no. 12, p. 124313, 2005.
[25] G. W. Cong, H. Y. Wei, P. F. Zhang, W. Q. Peng, J. J. Wu, X. L. Liu, C.
M. Jiao, W. G. Hu, Q. S. Zhu, and Z. G. Wang, "One-step growth of
ZnO from film to vertically well-aligned nanorods and the morphologydependent
Raman scattering," Applied Physics Letters, vol. 87, no. 23, p.
231903, 2005.
[26] G. Xiong, U. Pal, and J. G. Serrano, "Correlations among size, defects,
and photoluminescence in ZnO nanoparticles," Journal of Applied
Physics, vol. 101, no. 2, p. 024317, 2007.
[27] K.-W. Chae, Q. Zhang, J. S. Kim, Y.-H. Jeong, and G. Cao, "Lowtemperature
solution growth of ZnO nanotube arrays.," Beilstein journal
of nanotechnology, vol. 1, no. 001, pp. 128, 2010.
[28] B. Panigrahy, M. Aslam, and D. Bahadur, "Controlled optical and
magnetic properties of ZnO nanorods by Ar ion irradiation," Applied
Physics Letters, vol. 98, no. 18, p. 183109, 2011.
[29] M. Haupt, Ladenburger, R. Sauer, K. Thonke, R. Glass, W. Roos, J. P.
Spatz, H. Rauscher, S. Riethmuller, and M. Moller, "Ultraviolet-emitting
ZnO nanowhiskers prepared by a vapor transport process on
prestructured surfaces with self-assembled polymers," Journal of
Applied Physics, vol. 93, no. 10, p. 6252, 2003.
[30] A. Kushwaha and M. Aslam, "Defect induced high photocurrent in
solution grown vertically aligned ZnO nanowire array films," Journal of
Applied Physics, vol. 112, no. 5, p. 054316, 2012.
[1] J. Bao, M. Zimmler, F. Capasso, X. Wang, and Z. F. Ren, "Broadband
ZnO single-nanowire light-emitting diode.," Nano letters, vol. 6, no. 8,
pp. 1719, 2006.
[2] A. I. Hochbaum and P. Yang, "Semiconductor nanowires for energy
conversion," Chemical reviews, vol. 110, no. 1, pp. 527, 2010.
[3] Q. Wan, Q. H. Li, Y. J. Chen, T. H. Wang, X. L. He, J. P. Li, and C. L.
Lin, "Fabrication and ethanol sensing characteristics of ZnO nanowire
gas sensors," Applied Physics Letters, vol. 84, no. 18, p. 3654, 2004.
[4] V. S. Sundaram and A. Mizel, "Surface effects on nanowire transport: a
numerical investigation using the Boltzmann equation," Journal of
Physics: Condensed Matter, vol. 16, no. 26, pp. 4697, 2004.
[5] U. Ozgur, Y. I. Alivov, C. Liu, M. Reshchikov, S. Dogan, V. Avrutin,
S.-J. Cho, and H. Morkoc, "A comprehensive review of ZnO materials
and devices," Journal of Applied Physics, vol. 98, no. 4, p. 041301,
2005.
[6] A. B. Djurisić and Y. H. Leung, "Optical properties of ZnO
nanostructures.," Small, vol. 2, no. 8-9, pp. 944, 2006.
[7] K. Vanheusden, W. L. Warren, C. H. Seager, D. R. Tallant, J. a. Voigt,
and B. E. Gnade, "Mechanisms behind green photoluminescence in ZnO
phosphor powders," Journal of Applied Physics, vol. 79, no. 10, p. 7983,
1996.
[8] S. A. Studenikin "Fabrication of green and orange photoluminescent,
undoped ZnO films using spray pyrolysis" Journal of Applied Physics,
Vol. 84, No. 4, pp. 2287, 1998.
[9] F. H. Leiter, H. R. Alves, A. Hofstaetter, D. M. Hofmann, B. K. Meyer,
and I. P. Institut, "The Oxygen Vacancy as the Origin of a Green
Emission in Undoped ZnO," phys. stat. sol. (b) 226, No. 1, R4-R5,
2001.
[10] B. Panigrahy, M. Aslam, D. S. Misra, M. Ghosh, and D. Bahadur,
"Defect-Related Emissions and Magnetization Properties of ZnO
Nanorods," Advanced Functional Materials, vol. 20, no. 7, pp. 1161,
2010.
[11] Y. Sato, H. Kusumi, H. Yamaguchi, T. Komiyama, and T. Aoyama,
"Photoconductive properties of ZnO crystals with post-growth
annealing," Physica B: Condensed Matter, vol. 376, no. 377, pp. 719,
2006.
[12] M. Rusop, "Post-growth annealing of zinc oxide thin films pulsed laser
deposited under enhanced oxygen pressure on quartz and silicon
substrates" Materials Science and Engineering: B, vol. 127, pp. 150,
2006.
[13] Q. Zhao, X. Y. Xu, X. F. Song, X. Z. Zhang, D. P. Yu, C. P. Li, and L.
Guo, "Enhanced field emission from ZnO nanorods via thermal
annealing in oxygen," Applied Physics Letters, vol. 88, no. 3, p. 033102,
2006.
[14] H. S. Kang, "Annealing effect on the property of ultraviolet and green
emissions of ZnO thin films," Journal of Applied Physics, vol. 95, no. 3,
p. 1246, 2004.
[15] Q. Xu, R. Hong, H. Huang, Z. Zhang, M. Zhang, X. Chen, and Z.
.Wu, "Laser annealing effect on optical and electrical properties of Al
doped ZnO films," Optics & Laser Technology, vol. 45, pp. 513, 2013.
[16] A. Kushwaha and M. Aslam, "Controlled growth of highly oriented ZnO
nanorod array on amorphous glass substrate and their optical and
electrical properties," International Journal of Nanoscience, vol. 10, no.
4-5, p. 635, 2011.
[17] S. Wang, Y. Song, and L. Jiang, "Photoresponsive surfaces with
controllable wettability," Journal of Photochemistry and Photobiology
C: Photochemistry Reviews, vol. 8, no. 1, pp. 18, 2007.
[18] N. Verplanck, Y. Coffinier, V. Thomy, and R. Boukherroub,
"Wettability Switching Techniques on Superhydrophobic Surfaces,"
Nanoscale Research Letters, vol. 2, no. 12, pp. 577, 2007.
[19] S. Patra, S. Sarkar, S. K. Bera, G. K. Paul, and R. Ghosh, "Influence of
surface topography and chemical structure on wettability of
electrodeposited ZnO thin films," Journal of Applied Physics, vol. 108,
no. 8, p. 083507, 2010.
[20] M. Sun, Y. Du, W. Hao, H. Xu, Y. Yu, and T. Wang, "Fabrication and
Wettability of ZnO Nanorod Array," J. Mater. Sci. Technol vol. 25, no.
1, pp. 53, 2009.
[21] V. R. Shinde, C. D. Lokhande, R. S. Mane, and S.-H. Han,
"Hydrophobic and textured ZnO films deposited by chemical bath
deposition: annealing effect," Applied Surface Science, vol. 245, no. 1-
4, pp. 407, 2005.
[22] R. Sun, A. Nakajima, A. Fujishima, T. Watanabe, and K. Hashimoto,
"Photoinduced Surface Wettability Conversion of ZnO and TiO 2 Thin
Films," J Phys. Chem. B, vol. 105, no. 4, pp. 1984, 2001.
[23] A. C. Gandhi, H.-J. Hung, P.-H. Shih, C.-L. Cheng, Y.-R. Ma, and S.
Wu, "In Situ Confocal Raman Mapping Study of a Single Ti-Assisted
ZnO Nanowire.," Nanoscale research letters, vol. 5, no. 3, pp. 581,
2009.
[24] K. Alim, V. Fonoberov, M. Shamsa, and A. Balandin, "Micro-Raman
investigation of optical phonons in ZnO nanocrystals," Journal of
Applied Physics, vol. 97, no. 12, p. 124313, 2005.
[25] G. W. Cong, H. Y. Wei, P. F. Zhang, W. Q. Peng, J. J. Wu, X. L. Liu, C.
M. Jiao, W. G. Hu, Q. S. Zhu, and Z. G. Wang, "One-step growth of
ZnO from film to vertically well-aligned nanorods and the morphologydependent
Raman scattering," Applied Physics Letters, vol. 87, no. 23, p.
231903, 2005.
[26] G. Xiong, U. Pal, and J. G. Serrano, "Correlations among size, defects,
and photoluminescence in ZnO nanoparticles," Journal of Applied
Physics, vol. 101, no. 2, p. 024317, 2007.
[27] K.-W. Chae, Q. Zhang, J. S. Kim, Y.-H. Jeong, and G. Cao, "Lowtemperature
solution growth of ZnO nanotube arrays.," Beilstein journal
of nanotechnology, vol. 1, no. 001, pp. 128, 2010.
[28] B. Panigrahy, M. Aslam, and D. Bahadur, "Controlled optical and
magnetic properties of ZnO nanorods by Ar ion irradiation," Applied
Physics Letters, vol. 98, no. 18, p. 183109, 2011.
[29] M. Haupt, Ladenburger, R. Sauer, K. Thonke, R. Glass, W. Roos, J. P.
Spatz, H. Rauscher, S. Riethmuller, and M. Moller, "Ultraviolet-emitting
ZnO nanowhiskers prepared by a vapor transport process on
prestructured surfaces with self-assembled polymers," Journal of
Applied Physics, vol. 93, no. 10, p. 6252, 2003.
[30] A. Kushwaha and M. Aslam, "Defect induced high photocurrent in
solution grown vertically aligned ZnO nanowire array films," Journal of
Applied Physics, vol. 112, no. 5, p. 054316, 2012.
@article{"International Journal of Engineering, Mathematical and Physical Sciences:52184", author = "Ajay Kushwaha and Hemen Kalita and M. Aslam", title = "Effect of Oxygen Annealing on the Surface Defects and Photoconductivity of Vertically Aligned ZnO Nanowire Array", abstract = "Post growth annealing of solution grown ZnO
nanowire array is performed under controlled oxygen ambience. The
role of annealing over surface defects and their consequence on
dark/photo-conductivity and photosensitivity of nanowire array is
investigated. Surface defect properties are explored using various
measurement tools such as contact angle, photoluminescence, Raman
spectroscopy and XPS measurements. The contact angle of the NW
films reduces due to oxygen annealing and nanowire film surface
changes from hydrophobic (96°) to hydrophilic (16°). Raman and
XPS spectroscopy reveal that oxygen annealing improves the crystal
quality of the nanowire films. The defect band emission intensity
(relative to band edge emission, ID/IUV) reduces from 1.3 to 0.2 after
annealing at 600 °C at 10 SCCM flow of oxygen. An order
enhancement in dark conductivity is observed in O2 annealed
samples, while photoconductivity is found to be slightly reduced due
to lower concentration of surface related oxygen defects.", keywords = "Zinc Oxide, Surface defects, Photoluminescence,
Photoconductivity, Photosensor and Nanowire thin film.", volume = "7", number = "2", pages = "210-6", }
