Ionization of hexamethyldisilane for SiC deposition

We developed the SiC deposition technique by using ion beam induced deposition. In this technique, hexamethyldisilane was excited through impact with Ar ions and fragmented ions were deposited on the substrate. In this work the fragmentation mechanism of hexamethyldisilane is studied using Mass Spectrometry. To discuss the effect of excitation energy, hexamethyldisilane was excited by impact with electrons. With an impact of electrons in an energy range of 10-70 eV, two types of fragmentation, namely, the Si-Si bond dissociation and the methyl radical loss, were observed. The formation of these fragment ions, most probably trimethylsilyl cations, contributed to SiC deposition. (C) 2002 Elsevier Science B.V. All rights reserved.