Ferroelectricity in Orthorhombic Zirconia Thin Films.

Ferroelectric fluorite oxides such as hafnium (HfO)-based materials are one of the most promising candidates for future large-scale integrated circuits (ICs), while zirconia (ZrO)-based fluorite materials, which have the same structure as HfO and , are usually thought to be anti- or ferroelectric-like. Here, we report a remanent polarization () of ∼15 μC/cm in orthorhombic ZrO thin films at 77 K. This ferroelectricity arises from an electric field-induced antiferroelectric to ferroelectric phase transition, which is particularly noticeable at 77 K.