Ion Beam Analysis of Ge/Si Dots Grown on Ultrathin SiO2 Interlayers


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Monolayer (ML) thick Ge deposition on (100) Si substrates by molecular beam epitaxy (MBE) technique using an ultrathin SiO2 interlayer has been studied by ion beam analysis and photoluminescence (PL). The dependence of the Ge layer growth mode on the amount of the deposited Ge and the SiO2 thickness has been investigated. Atomic hydrogen treatment has been performed in order to passivate non-radiative recombination channels and to enhance the PL intensity. We conclude the formation of Ge quantum dots for the sample with the thickest Ge and SiO2 layers (9 Å and 1 ML, respectively).



Materials Science Forum (Volumes 514-516)

Edited by:

Paula Maria Vilarinho




A. Fonseca et al., "Ion Beam Analysis of Ge/Si Dots Grown on Ultrathin SiO2 Interlayers", Materials Science Forum, Vols. 514-516, pp. 1121-1124, 2006

Online since:

May 2006




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8 Intensity (a. u. ) Energy (eV) as-grown passivated (b) Energy (eV) 3Å Ge 6Å Ge 9Å Ge Si features (a) Fig. 4 - PL spectra for samples containing (a) 1 ML of SiO2 and 3, 6 and 9 Å of Ge and (b) comparision between the as-grown and passivated samples having 9 Å of Ge and 1 ML of SiO2. The spectra were collected at 5 K and with an excitation power of 36 mW.