Novel flexible and thin capacitors with Mn-doped SrTiO/sub 3/ thin films on polyimide films

Novel SrTiO/sub 3/-based flexible and thin capacitors with total thickness of only 40 /spl mu/m have been developed as decoupling capacitors. The sputter-deposited SrTiO/sub 3/ thin film capacitors, with electroplated Cu terminals, are fabricated on polyimide-coated Si substrates using photolithography and thin film process technologies. The capacitor parts, including polyimide, are finally peeled off from the Si substrates. Manganese impurity doping into the SrTiO/sub 3/ is effective for good uniformity and low temperature deposition down to 250/spl deg/C. A highly elastic molybdenum film, as a part of the bottom electrodes, successfully suppresses the polyimide contraction during SrTiO/sub 3/ deposition up to 400/spl deg/C. The diced flexible capacitor shows a large capacitance density of 3.2 nF/mm/sup 2/, and low leakage current of 10/sup -7/ A/cm/sup 2/ at 10 V.