Composition control and ferroelectric properties of sidewalls in integrated three-dimensional SrBi2Ta2O9-based ferroelectric capacitors

The difficult scaling of ferroelectric random access memories with the complementary metal-oxide semiconductor technology roadmap requires integration of three-dimensional (3D) ferroelectric capacitors (FeCAP’s). In this work the unusual electrical behavior of 3D FeCAP sidewalls was studied by compa...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Journal of applied physics 2005-09, Vol.98 (5)
Hauptverfasser: Goux, L., Lisoni, J. G., Schwitters, M., Paraschiv, V., Maes, D., Haspeslagh, L., Wouters, D. J., Menou, N., Turquat, Ch, Madigou, V., Muller, Ch, Zambrano, R.
Format: Artikel
Sprache:eng
Schlagworte:
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:The difficult scaling of ferroelectric random access memories with the complementary metal-oxide semiconductor technology roadmap requires integration of three-dimensional (3D) ferroelectric capacitors (FeCAP’s). In this work the unusual electrical behavior of 3D FeCAP sidewalls was studied by comparing the electrical properties of two-dimensional and 3D integrated FeCAP structures. We evidenced composition variations of the SrBi2Ta2O9 (SBT) film in the sidewalls with marked bismuth segregation during metal-organic chemical-vapor deposition (MOCVD) of the SBT film. The segregation was reduced after decreasing the deposition temperature from 440°C, whereby the Bi-rich phase in the sidewalls does not contribute to polarization, down to 405°C, whereby sidewall SBT contributes to polarization. After further optimization of the MOCVD conditions at 405°C, the segregation is minimized and the ferroelectric contribution of the sidewall SBT is almost the same as the contribution of the planar SBT. As a result, 3D FeCAP’s integrated up to metal interconnection exhibit a remnant polarization Pr∼7.5μC∕cm2.
ISSN:0021-8979
1089-7550
DOI:10.1063/1.2012508