Structural characterization of interfacial oxide in ultrathin ZrO{sub}2/Si(100) system

摘要

ZrO{sub}2/SiO{sub}x:Zr/Si(100) stacked structures were formed by ZrO{sub}2 evaporation in O{sub}2 ambient and subsequent 500℃ anneal in dry O{sub}2. A distinct change in the LO-phonon spectra with the Zr-incorporation into the SiO{sub}2 network was observed by FT-IR-ATR measurements. Although ～1nm-thick SiN{sub}x layer grown by NH{sub}3 anneal at 700℃ prior to the ZrO{sub}2 evaporation suppresses the interfacial oxidation in O{sub}2 annealing at 500℃ for 5min, the surface oxidation of the ultrathin SiN{sub}x layer proceeds accompanied with the movement of nitrogen atoms from the oxidized SiN{sub}x surface to the Si surface. As a result, the interfacial layer thickness is increased with no significant changes in nitrogen bonding features at the interface.