Investigation of thin-film nanocomposite materials by monochromatic null ellipsometry

Possibility of a method ellipsometry application for investigation of the multi-layer films and structures was shown. Reliability of obtaining data was confirmed with independent method of X-rays photoelectron spectroscopy. Layerwise composition of HfO
₂
/SiO
₂
/Si stack was studied. It was shown that interfacial layer of hafnium silicate was formed between HfO
₂
film and Si substrate. Investigation of the HfO
₂
/Si, ZrO
₂
/Si, Ta
₂
O
₅
/Si, Al
₂
O
₃
/Si structures after annealing in oxygen ambient disclosed that the oxides under study were permeable for diffusion of oxygen. As a result the thickness of SiO
₂
layer was increased during annealing process. It was revealed, that Al
₂
O
₃
-films were oxygen-tight. The developed ellipsometric method was used for optimization of the (HfO
₂
)
_x
(Al
₂
O
₃
)
_1-x
layers obtaining.