title: Robust high-κ response in molecularly thin perovskite nanosheets.
abstract: Size-induced suppression of permittivity in perovskite thin films is a fundamental problem that has remained unresolved for decades. This size-effect issue becomes increasingly important due to the integration of perovskite nanofilms into high-κ capacitors, as well as concerns that intrinsic size effects may limit their device performance. Here, we report a new approach to produce robust high-κ nanodielectrics using perovskite nanosheet (Ca2Nb3O10), a new class of nanomaterials that is derived from layered compounds by exfoliation. By a solution-based bottom-up approach using perovskite nanosheets, we have successfully fabricated multilayer nanofilms directly on SrRuO3 or Pt substrates without any interfacial dead layers. These nanofilms exhibit high dielectric constant (>200), the largest value seen so far in perovskite films with a thickness down to 10 nm. Furthermore, the superior high-κ properties are a size-effect-free characteristic with low leakage current density (<10(-7) A cm(-2)). Our work provides a key for understanding the size effect and also represents a step toward a bottom-up paradigm for future high-κ devices.
authors.affiliation: International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan. osada.minoru@nims.go.jp
authors.forename: Minoru
authors.initials: M
authors.lastname: Osada
authors.forename: Kosho
authors.initials: K
authors.lastname: Akatsuka
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Ebina
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Funakubo
authors.forename: Kanta
authors.initials: K
authors.lastname: Ono
authors.forename: Kazunori
authors.initials: K
authors.lastname: Takada
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Sasaki