Radiation Measurements PERGAMON Radiation Measurements31 (1999)701-704 FABRICATION AND OPTICAL CHARACTERIZATION OF CADMIUM SULFIDE NEEDLES USING NUCLEAR TRACK MEMBRANE L.Q. PENG*, S.C. WANG*, X. JU*, H. XIAO*, H. CHEN** AND Y.J. HE** *Laboratory of Nuclear Analysis, Institute of High Energy Physics, Chinese Academy of Science, P.O.Box 2732, Beijing 100080, China **Department of Physics, Tsinghua University, Beijing 100084, China ABSTRACT Cadmium sulfide needles with a diameter of 0.2 ~tm have been fabricated in nuclear track polyethylene-terephthalate (PET) membrane by electrochemically depositing from organic solvent dimethylsulfoxide (DMSO) containing CdC12 and elemental sulfur at the temperature 110°C. The characterization of the sample of CdS needles was studied by scanning electron microscope, X-ray diffraction, absorption and photoluminescence spectra. The optical experiments show that in the sample of CdS needles there is an absorption peak that could be assigned to the interface states of the CdS needles. KEYWORDS CdS needles; optical spectra; nuclear track membrane. INTRODUCTION Template synthesis is an elegant chemical approach for the fabrication of nanowires and has attracted more and more attention. Arrays of metal (Martin, 1994, Wang et al., 1996, Sch6nenberger et al., 1997), semiconductor (Routkevitch et al., 1996), conducting polymer nanowires (Piraux et al., 1997) and carbon nanotubes (Li et aL, 1996) are obtained by electrodeposition or other methods in porous templates such as anodic aluminum oxide films and nuclear track membranes. Applications of these materials include arrays of electron field emitters (de Heer, et al., 1995), nanoelectrodes for electrochemical experiments (Menon et aL, 1995), magnetic sensors based on the giant magnetio- resistance effect (Piraux et aL, 1994) and anisotropic optical filters (Foss et al., 1994). Although CdS nanowire arrays with diameter as small as 9urn have been fabricated in anodic aluminum oxide films with the oxide barrier layer separating the AI substrate and the porous aluminum oxide (Routkevitch et at, 1996), there is a main constraint in the experiments such as absorption spectra in order to separate CdS nanowire arrays from the AI substrate. However, the characterization of CdS nanowire arrays can be studied thoroughly if they are fabricated in nuclear track membranes. In the present paper, we report the fabrication and optical characterization of CdS needles with a diameter of 0.2~m in nuclear track membranes by electrochemically depositing from organic solvent dimethylsulfoxide (DMSO). EXPERIMENTAL SECTION Commercial polyethylene-terephthalate (PET) film from Japan with a thickness of 161un was irradiated at the tandem accelerator of China Institute of Atomic Energy, Beijing, with sulfur ions (4.1MeV/amu) with a fluence of 3 × 108 ions per cm 2. The ion irradiated PET film was UV irradiated for track sensitization. The film was then sensitized with ammonia water moreover. (We found that the effect of track sensitization on PET treated with ammonia water was nearly as same as that with 1350-4487/99/$ - see frontmatter© 1999 Elsevier ScienceLtd.All rights reserved. PII: S1350-4487(99)00181-X