| 摘要 |
PROBLEM TO BE SOLVED: To obtain a thin film capacitor wherein the value of residual dielectric polarization, in sufficiently large, the center position of hysteresis is in the vicinity of zero volt, and which contributes to the reduction of a leakage current. SOLUTION: A thin film capacitor is provided with a lower part electrode 2 formed on MgO (100) single crystal substrate 1, a dielectric film 3 composed of dielectric material which has a perovskite type crystal structure epitaxially grown on the lower part electrode 2 and whose Curie temperature is equal to or lower than 200 deg.C, and an upper part electrode 4 formed on the dielectric film 3. Au-Pt is used for the lower part electrode 2, and BaTiO3 is used for the dielectric film 3. When the lattice constant of the surface of a substrate is as , and the original lattice constant of the dielectric material is ad which is expressed by the length of an (a) axis of the perovskite type crystal structure, relations of 1.002<=2a /as <=1.015 and as >=0.3935nm are satisfied. |
