Abstract
Epitaxial Bi4Ti3O12 (BTO) films with La0.5Sr0.5CoO3 (LSCO) or Pt bottom electrodes were grown on MgO(001) substrates by pulsed laser deposition. Surprisingly, a symmetric Pt/BTO/Pt capacitor showed a highly asymmetric polarization switching and an asymmetric Pt/BTO/LSCO capacitor revealed a nearly symmetric polarization switching. To understand these intriguing phenomena, Auger electron spectroscopy and x-ray photoemission spectroscopy depth-profiles were used. The evidences for interdiffusions at the bottom BTO/Pt interface were found. To get further understanding on the interfacial states, a capacitance-voltage (C-V) measurement was performed on the Pt/BTO/Pt capacitor. By fitting the C-V data with a back-to-back Schottky diode model, built-in voltages at the top and the bottom interfaces were determined to be 1.1 V and 3.2 V, respectively. From the obtained built-in voltages, an asymmetric band diagram for the Pt/BTO/Pt structure was suggested. Therefore, the imprint failure can be explained by existence of asymmetric interfacial states.
| Original language | English |
|---|---|
| Pages (from-to) | 3-8 |
| Number of pages | 6 |
| Journal | Materials Research Society Symposium - Proceedings |
| Volume | 477 |
| State | Published - 1997 |
| Event | Proceedings of the 1997 MRS Spring Meeting - San Francisco, CA, USA Duration: 31 Mar 1997 → … |