At the same time, neither ATR nor XRD studies can reveal
unambiguously where the SiO2 phase is located, i.e. at film/substrate
interface or embedded in the film volume. However, based on these
results and on the estimate of the film density, we can admit the
presence of SiO2 phase inside the volume of HfSiO layer. The latter will
be confirmed by TEM observations of as-deposited and annealed films