Nonvolatile Ferroelastic Strain from Flexoelectric Internal Bias Engineering

Ferroelectric materials, with a spontaneous polarization that is switchable by an applied electric field, are already used in electronics. Furthermore, internal bias in a ferroelectric shifts the whole polarization hysteresis loop, and the ability to control that would add another degree of freedom for device engineering. In this study, controlled deposition of stressed thin films onto ferroelectrics is used to control the internal bias via the flexoelectric effect. With this technique, strain-engineering concepts for silicon integrated circuits can be transferred, with the potential to individually tune myriad ferroelectric straintronic devices in a deeply scaled environment.