Substrate effect on morphology and photoluminescence from ZnO monopods and bipods

Abstract

A simple wet chemical bath deposition has been successfully deployed to fabricate zinc oxide (ZnO) nanostructures. For substrate free growth, the nanostructure is spindle like monopods. But when the nanostructures grow on the glass and quartz substrates, they are bipods (two monopods joined together base to base). Variation in the size of the spindles of the monopods and bipods and the particle size was observed due to the strain exists in the thin film due to lattice mismatch at the interface of the thin film and the substrates. The X-ray diffraction (XRD) and selected area diffraction results confirmed the hexagonal unit cell structures of the monopods and bipods. Also the growth rates of various planes are different and the growth is anisotropic. The substrate free grown monopods show visible photoluminescence (PL) at 421 nm. But the emission gets shifted by 3 and 6 nm for ZnO thin film deposited on quartz and glass substrates respectively due to interfacial strain. In case of ZnO on quartz substrate a strong ultra-violet (UV) peak was observed at 386 nm due to band edge transition. These emissions are also accompanied by few weaker emission peaks due to various defect related transition.

Keywords

monopods / bipods / particle-size / strain / photoluminescence (PL) / recombination

References

[1] Wong E M, Searson P C. ZnO quantum particle thin films fabricated by electrophoretic deposition. Applied Physics Letters, 1999, 74(20): 2939-2941

[2] Vanheusden K, Seager C H, Warren W L, Tallant D R, Voigt J A. Correlation between photoluminescence and oxygen vacancies in ZnO phosphors. Applied Physics Letters, 1996, 68(3): 403-405

[3] Wang H Q, Wang G Z, Jia L C, Tang C J, Li G H. Polychromatic visible photoluminescence in porous ZnO nanotubes. Phys J. D. Applied Physics (Berlin), 2007, 40: 6549-6553

[4] Samanta P K, Patra S K, Roy C P. Violet emission from flower-like bundle of ZnO nanosheets. Physica E, Low-Dimensional Systems and Nanostructures, 2009, 41(4): 664-667

[5] Ma Jina, Ji Fenga, Zhang De-hengb, Ma Hong-leia, Li Shu-ying. Optical and electronic properties of transparent conducting ZnO and ZnO:Al lms prepared by evaporating method. Thin Solid Films, 1999, 357: 98-101

[6] Baxter J B, Schmuttenmaer C A. Conductivity of ZnO Nanowires, Nanoparticles, and Thin Films Using Time-Resolved Terahertz Spectroscopy†. Journal of Physical Chemistry B, 2006, 110(50): 25229-25239

[7] Kong X Y, Wang Z L. Spontaneous polarization-induced nanohelixes, nanosprings, and nanorings of piezoelectric nanobelts. Nano Letters, 2003, 3(12): 1625-1631

[8] Yasuhide Nakamura. Solution-growth of Zinc oxide nanowires for dye-sensitized solar cells. MATERIALS • NNIN REU, Research Accomplishments, 2006, 74

[9] Huang M H, Mao S, Feick H, Yan H, Wu Y, Kind H, Weber E, Russo R, Yang P. Room-temperature ultraviolet nanowire nanolasers. Science, 2001, 292(5523): 1897-1899

[10] Bixia Lin and Zhuxi Fua, Yunbo Jia. Green luminescent center in undoped zinc oxide films deposited on silicon substrates. Applied Physics Letters, 2001, 79: 943-945

[11] Lee M K, Tu H F. Ultraviolet emission blueshift of ZnO related to Zn. Journal of Applied Physics, 2007, 101(12): 126103

[12] Liu M, Kitai A H, Mascher P. Point defects and luminescence centres in zinc oxide and zinc oxide doped with manganese. Journal of Luminescence, 1992, 54(1): 35-42

[13] Teng X M, Fan H T, Pan S S, Ye C, Li G H.. Photoluminescence of ZnO thin films on Si substrate with and without ITO buffer layer. Phys J. D. Applied Physics (Berlin), 2006, 39: 471

[14] Wu J J, Liu S C. Low-temperature growth of well-aligned ZnO nanorods by chemical vapor deposition. Advanced Materials (Deerfield Beach, Fla.), 2002, 14(3): 215-218

[15] Hu H, Huang X, Deng C, Chen X, Qian Y. Hydrothermal synthesis of ZnO nanowires and nanobelts on a large scale. Materials Chemistry and Physics, 2007, 106(1): 58-62

[16] Zhu Y W, Zhang H Z, Sun X C, Feng S Q, Xu J, Zhao Q, Xiang B, Wang R M, Yu D P. Efficient field emission from ZnO nanoneedle arrays. Applied Physics Letters, 2003, 83(1): 144

[17] Samanta P K, Basak S, Roy C P. Electrochemical growth of ZnO microspheres and nanosheets. Adv. Sci. Lett. (in press)

[18] Fouchet A, Prellier W, Mercey B, Méchin L, Kulkarni V N, Venkatesan T. Investigation of laser-ablated ZnO thin films grown with Zn metal target: A structural study. Journal of Applied Physics, 2004, 96(6): 3228

[19] Mondal S P, Das K, Dhar A, Ray S K. Characteristics of CdS nanowires grown in a porous alumina template using a two-cell method. Nanotechnology, 2007, 18(9): 095606

[20] Samanta P K, Patra S K, Chaudhuri P R. Visible emission from ZnO nanorods synthesized by a simple wet chemical method. International Journal of Nanoscience and Nanotechnology, 2009, 1(1-2): 81-90

[21] Sugunan A, Warad H C, Boman M, Dutta J. Zinc oxide nanowires in chemical bath on seeded substrates: Role of hexamine. J Sol-Gel Sci Techn. 2006, 39(1): 49-56

[22] Hu X L, Zhu Y J, Wang S W. Sonochemical and microwave-assisted synthesis of linked single-crystalline ZnO rods. Materials Chemistry and Physics, 2004, 88(2-3): 421-426

[23] Zeng H, Li Z, Cai W, Liu P. Strong localization effect in temperature dependence of violet-blue emission from ZnO nanoshells. Journal of Applied Physics, 2007, 102(10): 104307

[24] Wu J J, Liu S C. Low-Temperature Growth of Well-Aligned ZnO Nanorods by Chemical Vapor Deposition. Advanced Materials (Deerfield Beach, Fla.), 2002, 14(3): 215-218

[25] Xu P S, Sun Y M, Shi C S, Xu F Q, Pan H B. The electronic structure and spec-tral properties of ZnO and its defects. Nucl. Instrum. Methods Phys. Res. Sect. B., 2003, 199: 286

RIGHTS & PERMISSIONS

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg