Electronic device using zirconate titanate and barium titanate ferroelectrics in insulating layer

An electronic device including a MIS structure, wherein said MIS structure comprises:

• a silicon layer,
• a film formed directly on said silicon layer, and consisting essentially of a material selected from the group consisting of silicon oxide, silicon nitride, nitride oxide, TiO.sub.2 and Ta.sub.2 O.sub.5,
• a sub-insulating layer formed directly on said film by CVD or sputtering, and consisting essentially of at least a compound selected from the group consisting of lead titanate, lanthanum lead titanate, barium titanate, strontium titanate, barium strontium titanate, lead zirconate, and lanthanum lead zirconate,
• a main insulating layer formed directly on said sub-insulating layer by CVD or sputtering, and consisting essentially of zirconate titanate and,
• a layer formed on said main insulating layer, and consisting essentially of a conductor,
• wherein said main insulating layer has a perovskite type crystal structure, and exhibits ferroelectricity at ambient temperature, and wherein said sub-insulating layer consists essentially of barium titanate.

An electronic device including a capacitor structure, wherein said capacitor structure comprises:

• a first electrode consisting essentially of noble metal,
• a sub-insulating layer formed directly on said first electrode by CVD or sputtering, and consisting essentially of at least a compound selected from the group consisting of lead titanate, lanthanum lead titanate, barium titanate, strontium titanate, barium strontium titanate, lead zirconate, and lanthanum lead zirconate,
• a main insulating layer formed directly on said sub-insulating layer by CVD or sputtering, and consisting essentially of zirconate titanate, and
• a second electrode formed on said main insulating layer, and consisting essentially of a conductor,
• wherein said main insulating layer has a perovskite type crystal structure, and exhibits ferroelectricity at ambient temperature, and wherein said sub-insulating layer consists essentially of barium titanate.