Towards new devices on Si thanks to a combination of physical and chemical deposition techniques

An innovative combination of physical and chemical deposition methods has allowed the fabrication of an original columnar oxide heterostructure on Si, and the control of a novel multilevel mechano-electric coupling, which could be used as new integrated devices for data storage, sensing, energy harvesting and smart actuation applications.

Thanks to a collaboration between INL and IES, epitaxial columnar BaTiO3-δ films have been grown by molecular beam epitaxy (MBE) on columnar (La,Sr)MnO3 films elaborated by a water-based chemical solution deposition (CSD) technique on epitaxial SrTiO3/Si templates grown by MBE. It has been found that the ferroelectric polarization can be reversed, and a resistive switching can be measured, upon a mechanical load in the epitaxial BaTiO3−δ/La0.7Sr0.3MnO3/SrTiO3/Si columnar heterostructure. A flexoelectric effect has been found, stemming from substantial strain gradients that can be created with moderate loads. Simultaneously, mechanical effects on the local conductivity can be used to modulate a non-volatile resistive state of the BaTiO3−δ heterostructure. As a result, three different configurations of the system has become accessible on top of the usual voltage reversal of polarization and resistive states.

 

These results have been highlighted in the journal Small (vol 13, Issue 39) with a Front Cover:
http://onlinelibrary.wiley.com/doi/10.1002/smll.v13.39/issuetoc
and in the INSIS-CNRS web site:
http://www.cnrs.fr/insis/recherche/actualites/2018/01/dispositif-silicium.htm

Article in Techno Science.net du 30/01/2018

 

Légende :

Vue d’artiste d’une commutation mécanique d’états ferroélectriques et résistifs dans une hétérostructure colonnaire de BaTiO3-δ / (La,Sr)MnO3 épitaxiée sur Si.


Contact:

Romain BACHELET

 

Référence:

Electric and Mechanical Switching of Ferroelectric and Resistive States in Semiconducting BaTiO3–δ Films on Silicon.
A. Gómez, J. M. Vila‐Fungueiriño, R. Moalla, G. Saint‐Girons, J. Gázquez, M. Varela, R. Bachelet, M. Gich, F. Rivadulla and A. Carretero‐Genevrier
Small 13, 1701614 (2017)
DOI: 10.1002/smll.201701614

INL CNRS