The world's highest performance thin-film capacitors are being claimed by researchers at the International Center for Materials Nanoarchitectonics (MANA) near Tokyo.
Key is a high-permittivity (high-k) dielectric sheet around 1nm thick.
Dr Minoru Osada and colleagues created thin films based on titanium-niobate (TiNbO5, Ti2NbO7, Ti5NbO14) nano-sheets by delaminated layered oxides and stacking the sheets on an atomically flat SrRuO3 substrate, creating films 5-15nm thick.
"The solution-based room-temperature process using oxide nano-sheets as building blocks opens multiple possibilities for the development of high-k dielectrics in capacitor technology, gate insulators in organic field effect transistors, energy-storage devices, and also future flexible electronics," said the Center.
Thin-film capacitors made with these films achieve a permittivity of 160-300.
"Good insulating, high-k nano-films are expected to be key to future applications as predicted by the International Technology Roadmap for Semiconductors," said the Center.
In these nano-sheets, according to the researchers, the octahedral distortion inherent to site engineering by Nb doping results in a giant molecular polarisability.
MANA is based at the National Institute for Material Science (NIMS) in Tsukuba City and the research group is led by Osada and principal investigator Dr Takayoshi Sasaki.
There is a paper in the journal Advanced Functional Materials: "Controlled polarizability of one-nanometer-thick oxide nanosheets for tailored, high-k nano-dielectrics".