Abstract
Valence- and conduction-band edges of ultrathin oxides (SiO2, HfO2, Hf0.7 Si0.3 O2, ZrO2, and Al2 O3) grown on a silicon substrate have been measured using ultraviolet photoemission and inverse photoemission spectroscopies in the same UHV chamber. The combination of these two techniques has enabled the direct determination of the oxide energy gaps as well as the offsets of the oxide valence- and conduction-band edges from those of the silicon substrate. These results are supplemented with synchrotron x-ray photoemission spectroscopy measurements allowing further characterization of the oxide composition and the evaluation of the silicon substrate contribution to the spectra. The electron affinity has also been systematically measured on the same samples. We find reasonably good agreement with earlier experiments where assumptions regarding energy-gap values were needed to establish the conduction-band offsets. The systematics of our photoemission and inverse photoemission results on different ultrathin films provide a comprehensive comparison of these related systems.
| Original language | English |
|---|---|
| Article number | 085114 |
| Journal | Physical Review B - Condensed Matter and Materials Physics |
| Volume | 78 |
| Issue number | 8 |
| DOIs | |
| Publication status | Published - Aug 12 2008 |
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ASJC Scopus subject areas
- Condensed Matter Physics
Cite this
Band offsets of ultrathin high- κ oxide films with Si. / Bersch, Eric; Rangan, Sylvie; Bartynski, Robert Allen; Garfunkel, Eric; Vescovo, Elio.
In: Physical Review B - Condensed Matter and Materials Physics, Vol. 78, No. 8, 085114, 12.08.2008.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Band offsets of ultrathin high- κ oxide films with Si
AU - Bersch, Eric
AU - Rangan, Sylvie
AU - Bartynski, Robert Allen
AU - Garfunkel, Eric
AU - Vescovo, Elio
PY - 2008/8/12
Y1 - 2008/8/12
N2 - Valence- and conduction-band edges of ultrathin oxides (SiO2, HfO2, Hf0.7 Si0.3 O2, ZrO2, and Al2 O3) grown on a silicon substrate have been measured using ultraviolet photoemission and inverse photoemission spectroscopies in the same UHV chamber. The combination of these two techniques has enabled the direct determination of the oxide energy gaps as well as the offsets of the oxide valence- and conduction-band edges from those of the silicon substrate. These results are supplemented with synchrotron x-ray photoemission spectroscopy measurements allowing further characterization of the oxide composition and the evaluation of the silicon substrate contribution to the spectra. The electron affinity has also been systematically measured on the same samples. We find reasonably good agreement with earlier experiments where assumptions regarding energy-gap values were needed to establish the conduction-band offsets. The systematics of our photoemission and inverse photoemission results on different ultrathin films provide a comprehensive comparison of these related systems.
AB - Valence- and conduction-band edges of ultrathin oxides (SiO2, HfO2, Hf0.7 Si0.3 O2, ZrO2, and Al2 O3) grown on a silicon substrate have been measured using ultraviolet photoemission and inverse photoemission spectroscopies in the same UHV chamber. The combination of these two techniques has enabled the direct determination of the oxide energy gaps as well as the offsets of the oxide valence- and conduction-band edges from those of the silicon substrate. These results are supplemented with synchrotron x-ray photoemission spectroscopy measurements allowing further characterization of the oxide composition and the evaluation of the silicon substrate contribution to the spectra. The electron affinity has also been systematically measured on the same samples. We find reasonably good agreement with earlier experiments where assumptions regarding energy-gap values were needed to establish the conduction-band offsets. The systematics of our photoemission and inverse photoemission results on different ultrathin films provide a comprehensive comparison of these related systems.
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U2 - 10.1103/PhysRevB.78.085114
DO - 10.1103/PhysRevB.78.085114
M3 - Article
VL - 78
JO - Physical Review B-Condensed Matter
JF - Physical Review B-Condensed Matter
SN - 1098-0121
IS - 8
M1 - 085114
ER -