Citation
Ortiz Esteban, María Isabel and Rodríguez Domínguez, Andrés and Sangrador García, Jesús and Ballesteros Pérez, Carmen Inés and Kanyinda-Malu, C. and Rodríguez Rodríguez, Tomás
(2008).
Structural stability of SiGe nanoparticles under "in situ" electron beam irradiation in TEM.
pp..
ISSN 1742-6588.
https://doi.org/10.1088/1742-6596/126/1/012023.
Abstract
The structure of amorphous and crystalline SiGe nanoparticles, embedded in a
dielectric medium, SiO2, and its stability under “in situ” electron beam irradiation is reported.
High-resolution transmission electron microscopy and electron-diffraction pattern simulation
by fast Fourier transform was used to analyze the crystal structure of the SiGe nanoparticles.
Electron beam irradiation induces structural alternate order-disorder transitions in the
nanoparticles for irradiation effects are mainly associated to the density of current. For
irradiation with current densities < 7 A·cm-2 no effects are observed in the as-deposited
amorphous samples, whereas in the crystallized samples, SiGe nanocrystals show higher
stability and no effects are observed for irradiation densities of current < 50 A·cm-2. Irradiation
with densities of current greater than these thresholds cause consecutive amorphous-crystalline
or crystalline-amorphous structure transitions respectively for both amorphous and crystallized
nanoparticles. A hexagonal structure is proposed for those nanocrystals obtained after
irradiation in the as deposited amorphous samples.