Acta Phys. -Chim. Sin. ›› 2010, Vol. 26 ›› Issue (10): 2840-2844.doi: 10.3866/PKU.WHXB20101024

• PHYSICAL CHEMISTRY OF MATERIALS • Previous Articles     Next Articles

Structure and Formation Mechanism of Sn-Doped ZnO Nanoneedles

WANG Jie, ZHUANG Hui-Zhao, XUE Cheng-Shan, LI Jun-Lin, XU Peng   

  1. Institute of Semiconductors, Shandong Normal University, Jinan 250014, P. R. China
  • Received:2010-06-27 Revised:2010-07-23 Published:2010-09-27
  • Contact: ZHUANG Hui-Zhao E-mail:zhuanghuizhao@sdnu.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (90201025, 90301002).

Abstract:

We synthesized Sn -doped ZnO nanoneedles on Si(111) substrates in two steps: sputtering and thermal oxidation. First, a thin layer of the Sn :Zn films was deposited onto the Si(111) substrates ina JCK -500A radio -frequency magnetron sputtering system. Sn-doped ZnO nanoneedles were then grown by simple thermal oxidation of the as-deposited films at 650 oC in Ar atmosphere. The structural, componential, and optical properties of the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high -resolution transmission electron microscopy (HRTEM), energy dispersive X-ray (EDX) spectroscopy, and photoluminescence (PL) spectroscopy. The results reveal that the ZnO nanoneedles doped with 2.5%(x, atomic ratio) Sn are single crystalline with a wurtzite hexagonal structure. The lengths of the grown nanoneedles vary between 1 and 3μm. The root diameters of the needles range between 200 and 500 nm while the tips have an average diameter of about 40 nm. Moreover, most of the Sn-doped ZnO nanoneedles are of high crystal quality. Room temperature PL spectroscopy shows a blue-shift from the bulk bandgap emission, which can be attributed toa Sn composition in the nanoneedles as detected by EDX. Based on the reaction conditions, the growth mechanism of the Sn-doped ZnO nanoneedles was also discussed.

Key words: Nanostructure, ZnO, Sn-doping, Sputtering, Optical property, Formation mechanism