High-density capacitors based on amorphous BaTiO3 layers grown under hydrogen containing atmosphere

Addition of hydrogen (H-2) during the sputter deposition of BaTiO3 amorphous thin films drastically modifies their dielectric properties. Films grown under hydrogen containing atmospheres display large capacitances (several mu F/cm(2) for 1 mu m thick films), that are hundred times higher than capacitances measured for films grown without hydrogen. This is explained by the formation of a double-layer capacitor which arises from mobile protons (protonic conduction with an activation energy around 0.3 eV). These films could find applications for the elaboration of integrated supercapacitors. (c) 2007 American Institute of Physics.