Patent ID: 7528088

Claim:
An electronic device having dielectric layers comprised of barium titanate as their main ingredient, wherein in a plurality of ceramic grains forming said dielectric layers, a ratio of a number of ceramic grains, having a crystal grain boundary that is 1 nm or less in thickness and is present between that ceramic grain and another ceramic grain adjoining that ceramic grain, is 30% to 95% of the total number of the ceramic grains included in said dielectric layer, the dielectric layers include, as sub ingredients, (a) magnesium oxide, (b) manganese (Mn) oxide and/or chromium (Cr) oxide, (c) rare earth oxide, (d) vanadium oxide, tungsten oxide, tantalum oxide, and/or niobium oxide and (e) a glass ingredient, and with respect to the barium titanate as 100 mol, the magnesium oxide is included in an amount of more than 0 to 2 mol or less, a total of the manganese oxide and chromium oxide, converted to MnO and Cr 2 O 3 , is more than 0 to 0.5 mol or less, the rare earth oxide is included in an amount of more than 0 to less than 4 mol, a total of the vanadium oxide, tungsten oxide, tantalum oxide, and/or niobium oxide is more than 0 to 0.5 mol or less, and the glass ingredient is included in an amount of more than 0.5 to less than 6 mol.