Charge trapping behavior in organic–inorganic alloy films grown by molecular layer deposition from trimethylaluminum, p-phenylenediamine and water

Abstract

Organic–inorganic hybrid or alloy films have great potential as a functional material because they have structural flexibility owing to the presence of an organic moiety. Here organic–inorganic hybrid films were grown by molecular layer deposition (MLD) by using trimethylaluminum and p-phenylenediamine. Although the hybrid films could be grown via the self-limiting growth mechanism of MLD, the hybrid films were severely air sensitive. The stability problem of the hybrid films could be solved by alloying the hybrid layer with Al2O3 layers. The alloy films, which were grown by repeating supercycles with one subcycle for the hybrid layer and four subcycles for the Al2O3 layers, showed excellent dielectric properties: a leakage current density of ∼2.3 × 10−8 A cm−2 at 1 MV cm−1; a dielectric breakdown field at ∼2.9 MV cm−1; and a dielectric constant of ∼6.2. Interestingly, charge trapping behavior was clearly observed in the alloy film. The charge trapping ability of the alloy film was verified with a charge trapping memory capacitor in which the alloy film was inserted as a charge trapping layer.