Schafranek, Robert ; Li, Shunyi ; Chen, Feng ; Wu, Wenbin ; Klein, Andreas (2022)
PbTiO₃/SrTiO₃ interface: Energy band alignment and its relation to the limits of Fermi level variation.
In: Physical Review B, 84 (4)
doi: 10.26083/tuprints-00021173
Artikel, Zweitveröffentlichung, Verlagsversion
Kurzbeschreibung (Abstract)
The interface formation between PbTiO₃ and SrTiO₃ has been studied by in situ photoelectron spectroscopy. A valence band offset of 1.1±0.1eV, corresponding to a conduction band offset of 1.3±0.1eV, is determined. These values are in good agreement with the band offsets estimated from measured ionization potentials of SrTiO₃ and PbTiO₃ surfaces. The observed band offsets are also in line with a ~1.1eV difference in barrier heights of PbTiO₃ in contact with different electrode materials as compared to barrier heights of SrTiO₃ with the same electrode materials. The results indicate that the band alignment is not strongly affected by Fermi level pinning and that the barrier heights are transitive. The limits of Fermi level variation observed from a number of thin films prepared on different substrates with different conditions are the same for both materials when these are aligned following the experimentally determined band offsets. By further comparing electrical conductivities reported for SrTiO₃ and PbTiO₃, it is suggested that the range of Fermi level position in the bulk of these materials, which corresponds to the range of observed conductivities, is comparable to the range of Fermi level position at interfaces with different contact materials. In particular the possibly low barrier height for electron injection into SrTiO₃ is consistent with the metallic conduction of donor doped or reduced SrTiO₃, while barrier heights ≳1eV for PbTiO₃ are consistent with the high resistivity even at high doping concentrations. The variation of barrier heights at interfaces therefore provides access to the range of possible Fermi level positions in the interior of any, including insulating, materials, which is relevant for understanding defect properties.
| Typ des Eintrags: | Artikel |
|---|---|
| Erschienen: | 2022 |
| Autor(en): | Schafranek, Robert ; Li, Shunyi ; Chen, Feng ; Wu, Wenbin ; Klein, Andreas |
| Art des Eintrags: | Zweitveröffentlichung |
| Titel: | PbTiO₃/SrTiO₃ interface: Energy band alignment and its relation to the limits of Fermi level variation |
| Sprache: | Englisch |
| Publikationsjahr: | 2022 |
| Verlag: | American Physical Society |
| Titel der Zeitschrift, Zeitung oder Schriftenreihe: | Physical Review B |
| Jahrgang/Volume einer Zeitschrift: | 84 |
| (Heft-)Nummer: | 4 |
| Kollation: | 7 Seiten |
| DOI: | 10.26083/tuprints-00021173 |
| URL / URN: | https://tuprints.ulb.tu-darmstadt.de/21173 |
| Zugehörige Links: | |
| Herkunft: | Zweitveröffentlichungsservice |
| Kurzbeschreibung (Abstract): | The interface formation between PbTiO₃ and SrTiO₃ has been studied by in situ photoelectron spectroscopy. A valence band offset of 1.1±0.1eV, corresponding to a conduction band offset of 1.3±0.1eV, is determined. These values are in good agreement with the band offsets estimated from measured ionization potentials of SrTiO₃ and PbTiO₃ surfaces. The observed band offsets are also in line with a ~1.1eV difference in barrier heights of PbTiO₃ in contact with different electrode materials as compared to barrier heights of SrTiO₃ with the same electrode materials. The results indicate that the band alignment is not strongly affected by Fermi level pinning and that the barrier heights are transitive. The limits of Fermi level variation observed from a number of thin films prepared on different substrates with different conditions are the same for both materials when these are aligned following the experimentally determined band offsets. By further comparing electrical conductivities reported for SrTiO₃ and PbTiO₃, it is suggested that the range of Fermi level position in the bulk of these materials, which corresponds to the range of observed conductivities, is comparable to the range of Fermi level position at interfaces with different contact materials. In particular the possibly low barrier height for electron injection into SrTiO₃ is consistent with the metallic conduction of donor doped or reduced SrTiO₃, while barrier heights ≳1eV for PbTiO₃ are consistent with the high resistivity even at high doping concentrations. The variation of barrier heights at interfaces therefore provides access to the range of possible Fermi level positions in the interior of any, including insulating, materials, which is relevant for understanding defect properties. |
| Status: | Verlagsversion |
| URN: | urn:nbn:de:tuda-tuprints-211731 |
| Sachgruppe der Dewey Dezimalklassifikatin (DDC): | 500 Naturwissenschaften und Mathematik > 530 Physik 600 Technik, Medizin, angewandte Wissenschaften > 620 Ingenieurwissenschaften und Maschinenbau |
| Fachbereich(e)/-gebiet(e): | 11 Fachbereich Material- und Geowissenschaften 11 Fachbereich Material- und Geowissenschaften > Materialwissenschaft 11 Fachbereich Material- und Geowissenschaften > Materialwissenschaft > Fachgebiet Oberflächenforschung DFG-Sonderforschungsbereiche (inkl. Transregio) DFG-Sonderforschungsbereiche (inkl. Transregio) > Sonderforschungsbereiche DFG-Sonderforschungsbereiche (inkl. Transregio) > Sonderforschungsbereiche > SFB 595: Elektrische Ermüdung DFG-Sonderforschungsbereiche (inkl. Transregio) > Sonderforschungsbereiche > SFB 595: Elektrische Ermüdung > B - Charakterisierung DFG-Sonderforschungsbereiche (inkl. Transregio) > Sonderforschungsbereiche > SFB 595: Elektrische Ermüdung > B - Charakterisierung > Teilprojekt B7:Polarisation und Ladung in elektrisch ermüdeten Ferroelektrika |
| Hinterlegungsdatum: | 20 Apr 2022 12:19 |
| Letzte Änderung: | 21 Apr 2022 05:03 |
| PPN: | |
| Zugehörige Links: | |
| Export: | |
| Suche nach Titel in: | TUfind oder in Google |
 |
Frage zum Eintrag |
Optionen (nur für Redakteure)
 |
Redaktionelle Details anzeigen |
Drucken
Impressum