T. Inoue et al., INTERMEDIATE AMORPHOUS LAYER FORMATION MECHANISM AT THE INTERFACE OF EPITAXIAL CEO2 LAYERS AND SI SUBSTRATES, JPN J A P 1, 32(4), 1993, pp. 1765-1767
The formation mechanism of an intermediate amorphous layer between epi
taxially grown CeO2 layers and silicon substrates is studied using cro
ss-sectional transmission electron microscopy and Auger electron spect
roscopy. The intermediate amorphous layer thickness increases after an
nealing at 800-degrees-C in air, whereas it decreases somewhat after a
nnealing in an ultrahigh vacuum. Auger in-depth analysis verifies that
the intermediate amorphous layer is silicon dioxide. The intermediate
oxide growth of the CeO2/Si structures due to intentional oxidation a
t 700 approximately 900-degrees-C in a dry oxygen ambient is analyzed
and the results indicate that the oxidation proceeds in an intermediat
e step between reaction limited and diffusion limited processes. The i
ntermediate amorphous layer formation mechanism is concluded to be oxy
gen diffusion through CeO2 layers and successive oxidation of silicon
at the interface.