Ultra-thin barium titanate nanocrystal monolayer capacitor with graphene electrode

Ultra-thin capacitor structures of barium titanate (BaTiO3, BTO) nanocube monolayers are fabricated using graphene as an electrode without high-temperature sintering. The capacitor consists of a self-assembled BTO nanocube monolayer (approximately 20 nm in thickness) and an eight-layer graphene electrode (≤3 nm in thickness) that are sandwiched metal electrodes. The graphene electrode functions as a barrier layer preventing the occurrence of short circuits caused by the penetration of metal species into the dielectric layer during the deposition process of the metal electrode, dramatically reducing the leakage current of the capacitor in comparison with the case without the graphene electrode. Furthermore, this approach is applicable to the fabrication of the graphene/BTO-nanocube-monolayer multi-stacked structures, demonstrating the potential to reduce the thickness of individual electrode/dielectric layers in multilayer ceramic capacitors down to less than 25 nm. This opens up possibilities for energy-efficient production of high-performance ceramic capacitors.