Controlled Polarizability of One‐Nanometer‐Thick Oxide Nanosheets for Tailored, High‐ κ Nanodielectrics

An important challenge in current microelectronics research is the development of techniques for making smaller, higher‐performance electronic components. In this context, the fabrication and integration of ultrathin high‐ κ dielectrics with good insulating properties is an important issue. Here, we report on a rational approach to produce high‐performance nanodielectrics using one‐nanometer‐thick oxide nanosheets as a building block. In titano niobate nanosheets (TiNbO 5 , Ti 2 NbO 7 , Ti 5 NbO 14 ), the octahedral distortion inherent to site‐engineering by Nb incorporation results in a giant molecular polarizability, and their multilayer nanofilms exhibit a high dielectric constant (160–320), the largest value seen so far in high‐ κ nanofilms with thickness down to 10 nm. Furthermore, these superior high‐ κ properties are fairly temperature‐independent with low leakage‐current density (<10 −7 A cm −2 ). This work may provide a new recipe for designing nanodielectrics desirable for practical high‐ κ devices.