Spatially-resolved valence-electron energy-loss spectroscopy of Zr-oxide and Zr-silicate films

We examined electronic structures in Zr-oxide (ZrO2) and Zr-silicate (ZrxSi1−xO2) films deposited on Si substrates by using valence-electron energy-loss spectroscopy combined with scanning transmission electron microscopy (the electron probe diameter was about 0.3 nm). Our analysis indicated that both valence-electron excitations in ZrO2 and in SiO2 occurred in the ZrxSi1−xO2 films. Therefore, the band gaps in the ZrxSi1−xO2 films should be dominated by an energy gap between O 2p and Zr 4d states.

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