Dielectric ceramic, method for producing the same, laminated ceramic electronic element, and method for producing the same
US6205015A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 20, 1999 |
| Grant date | Mar 20, 2001 |
| Priority date | — |
| Expiry date | Jan 20, 2019 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B35/4682
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A dielectric ceramic which exhibits an excellent electrostatic capacity-temperature characteristic; which allows use of a base metal such as nickel; which can be fired in a reducing atmosphere; and which is suitable for constituting a dielectric ceramic layer of a laminated ceramic electronic element such as a laminated ceramic capacitor; is obtained by firing barium titanate powder in which the c-axis/a-axis ratio in the perovskite structure is in the range of about 1.003 to 1.010 and the amount of OH groups in the crystal lattice is about 1 wt. % or less. The barium titanate powder a starting material preferably has a maximum particle size of about 0.5 .mu.m or less and an average particle size of about 0.1-0.3 .mu.m, and individual particles of the barium titanate powder comprise a low-crystallinity portion 21 and a high-crystallinity portion 23, with the diameter of the low-crystallinity portion being less than about 0.65 times the particle size of the powder. When sintered, the powder satisfies the ratio of (average grain size of the fired dielectric ceramic)/(average particle size of barium titanate powder serving as a starting material), which is referred to as R, of about 0…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.