Patent ID: 7417276

Claim:
A thin film capacitor comprising: a top electrode; a bottom electrode; and a dielectric film held between the top and bottom electrodes, the dielectric film being composed of at least cations Ba, Sr, and Ti and anion O; wherein concentration of Sr, Ti, and O ions are uniform along a growth direction of the dielectric film while the concentration of the Ba cation is non-uniform along the growth direction such that a reduced Ba-I region in which an average concentration of perovskite type Ba cations (Ba-I) is less than an average concentration of non-perovskite type Ba cations (Ba-II) exists at or near a boundary between at least one of the top and bottom electrodes, with ratio R=(atm % Ba-I)/[(atm % Ba-I)+(atm % Ba-II)] within a range of 0.1<R<0.2.