SHI induced re-crystallization of Ge implanted SiO2 films

Ge nanocrystals embedded in SiO2 matrix have been synthesized by swift heavy ion irradiation of Ge implanted SiO2 films. In the present study, 400 key Ge+ ions were implanted into SiO2 films at dose of 3 x 10(16) ions/cm(2) at room temperature. The as-implanted samples were irradiated with 150 MeV Ag12(+) ions with various fluences. Similarly 400 key Ge+ ions implanted into Silicon substrate at higher fluence at 573 K have been irradiated with 100 MeV Au8+ ions at room temperature (RT). These samples were subsequently characterized by XRD and Raman to understand the re-crystallization behavior. The XRD results confirm the presence of Ge crystallites in the irradiated samples. Rutherford backscattering spectrometry (RBS) was used to quantify the concentration of Ge in the SiO2 matrix. Variation in the nanocrystal size as a function of ion fluence is presented. The basic mechanism of ion beam induced re-crystallization has been discussed. (C) 2010 Elsevier B.V. All rights reserved.