High capacitance density by $CaCu3Ti4O12$ thin films

Metal-oxide-metal capacitors based on $CaCu3Ti4O12$ (CCTO) thin films, grown by metal-organic chemical vapor deposition and presenting a “brick wall” morphology, have been fabricated and characterized. In these capacitors, the coexistence of two Maxwell–Wagner related phenomena, i.e., the internal barrier layer capacitor and the electrode polarization effects, has been demonstrated and modeled. The detailed description of the involved mechanisms is discussed. High reliability and reproducibility in capacitors based on CCTO thin films can be achieved when the phenomena are controlled. A remarkable high capacitance density (about $100nF/mm2$⁠) has been obtained at room temperature in optimised processing.