AVS 51st International Symposium
    Nanometer-scale Science and Technology Thursday Sessions
       Session NS2-ThM

Paper NS2-ThM9
Time-Resolved X-Ray Excited Optical Luminescence Studies of Semiconductor Nanowires@footnote 1@

Thursday, November 18, 2004, 11:00 am, Room 213D

Session: Nanowires I
Presenter: R.A. Rosenberg, Argonne National Laboratory
Authors: R.A. Rosenberg, Argonne National Laboratory
G.K. Shenoy, Argonne National Laboratory
S.T. Lee, University of Hong Kong, China
F. Heigl, Canadian Synchrotron Radiation Facility
P.-S.G. Kim, University of Western Ontario, Canada
X.-T. Zhou, University of Western Ontario, Canada
T.K. Sham, University of Western Ontario, Canada
Correspondent: Click to Email
Due to quantum confinement effects nanostructures often exhibit unique and intriguing fluorescence behavior. X-ray excited optical luminescence (XEOL) provides the capability to chemically map the sites responsible for producing low energy (1-6 eV) fluorescence. By taking advantage of the time structure of the x-ray pulses at the Advanced Photon Source (APS, ~80 ps wide, 153 ns separation) it also possible to determine the dynamic behavior of the states involved in the luminescence. In this presentation we show how this technique can be utilized to understand the XEOL from silicon nanowires (~14 nm diameter) and show preliminary results from studies of II-VI nanoribbons. Previous XEOL studies of silicon nanowires have revealed luminescence in the 400-700 nm region.@footnote 2@@super ,@@footnote 3@ The lower wavelength part of the spectrum is associated with the oxide shell while longer wavelength emission is due to the silicon core. The present results support these findings. In addition we find that the longer wavelength, silicon core emission has a relatively short lifetime (<10 ns) while the oxide shell fluorescence has a much longer lifetime. These results will be discussed in terms of prior time-resolved work on porous silicon and related systems. In addition we plan to present initial results from studies of ZnS, ZnTe, CdSe and CdS nanoribbons. @FootnoteText@ @footnote 1@Work supported by U.S. Department of Energy, Office of Basic Energy Sciences under Contract No. W-31-109-ENG-38.@footnote 2@X.-H. Sun, Y.-H. Tang, R. Zhang, S.J. Naftel, R. Sammynaiken, T.K. Sham, H. Y. Peng, Y.-F. Zhang, N.B. Wong, and S.T. Lee, J. Appl. Phys. 90, 6379 (2001).@footnote 3@T.K. Sham, S.J. Naftel, P.-S. G. Kim, R. Sammynaiken, Y.H. Tang, I. Coulthard, A. Moewes, J.W. Freeland, Y.-F. Hu, S.T. Lee, Phys. Rev. B, to be published.