C. Godet et al., HELIUM ION-INDUCED STOICHIOMETRY MODIFICATION IN HYDROGENATED SILICON-OXIDE FILMS, Applied physics letters, 69(25), 1996, pp. 3845-3847
The stoichiometry of amorphous hydrogenated silicon oxide films, grown
in a dual-plasma system, has been investigated using elastic recoil d
etection (ERD), Rutherford backscattering, and infrared transmission.
During ERD measurement of H profiles, using a He-4(2+) beam of 3.0 MeV
, ion-induced depletion of hydrogen atoms was observed, homogeneous ov
er the 1 mu m film thickness. Si-rich films (with H essentially bonded
as Si-H) and nearly stoichiometric films (with H only bonded in Si-OH
configurations) have been compared. The depletion is more pronounced
in nearly stoichiometric oxides, whereas the apparent cross sections (
approximate to 1-2 nm(2)) are similar for both types of films. These o
bservations are discussed in terms of an electron excitation process,
with a subsequent chemical reconstruction via electron-hole recombinat
ion. (C) 1996 American Institute of Physics.