Homogeneous ZnO nanostructure arrays on GaAs substrates by two-step chemical bath synthesis
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ZnO nanostructures, including nanowires, nanorods, and nanoneedles, have been deposited on GaAs substrates by the two-step chemical bath synthesis. It was demonstrated that the O2-plasma treatment of GaAs substrates prior to the sol–gel deposition of seed layers was essential to conformally grow the nanostructures instead of 2D ZnO bunches and grains on the seed layers. Via adjusting the growth time and concentration of precursors, nanostructures with different average diameter (26–225 nm), length (0.98–2.29 μm), and density (1.9–15.3 × 109 cm−2) can be obtained. To the best of our knowledge, this is the first demonstration of ZnO nanostructure arrays grown on GaAs substrates by the two-step chemical bath synthesis. As an anti-reflection layer on GaAs-based solar cells, the array of ZnO nanoneedles with an average diameter of 125 nm, a moderate length of 2.29 μm, and the distribution density of 9.8 × 109 cm−2 has increased the power conversion efficiency from 7.3 to 12.2 %, corresponding to a 67 % improvement.
KeywordsZnO nanostructures Chemical synthesis Plasma treatment GaAs-based solar cells Energy conversion
The authors are grateful to the National Science Council of the Republic of China, Taiwan, for funding this research under contract no. NSC 100-2221-E-143-005-MY2 and the LED Lighting Research Center of NCKU for the assistance of device characterization.
- Huang JS, Lin CF (2008) Influences of ZnO sol–gel thin film characteristics on ZnO nanowire arrays prepared at low temperature using all solution-based processing. J Appl Phys 103:014304 1–014304 5Google Scholar
- Qiu J, Li X, He W, Park SJ, Kim HK, Hwang YH, Lee JH, Kim YD (2009) The growth mechanism and optical properties of ultralong ZnO nanorod arrays with a high aspect ratio by a preheating hydrothermal method. Nanotechnology 20:155603 1–155603 9Google Scholar
- Yang LL, Zhao QX, Willander M, Yang JH (2009) Effective way to control the size of well-aligned ZnO nanorod arrays with two-step chemical bath deposition. J Cryst Growth 311:1046–1050Google Scholar
- Zhang JY, Li PJ, Sun H, Shen X, Deng TS, Zhu KT, Zhang QF, Wu JL (2008) Ultraviolet electroluminescence from controlled arsenic-doped ZnO nanowire homojunctions. Appl Phys Lett 93:021116 1–021116 3Google Scholar