High-dielectric grain boundary layer ceramic material and preparation method of grain boundary layer ceramic substrate

Abstract

The invention discloses a high-dielectric grain boundary layer ceramic material and a preparation method of a grain boundary layer ceramic substrate. The ceramic material comprises a main body material strontium titanate, a donor materials La2O3 and Nb2O5, a sintering aid SiO2 and Li2CO3, and an acceptor material which is one or more of Bi2O3, CuO and ZnO; the sintering aid is used for reducing the sintering temperature of the ceramic and promoting crystal grain development; and the acceptor material is used as a grain boundary insulation coating material for oxidation sintering. Based on the ceramic material, the preparation of the grain boundary layer ceramic substrate is completed through secondary sintering, namely reduction semiconductor sintering and oxidation grain boundary layer insulation sintering. The ceramic substrate is prepared by doping the sintering aid into the ceramic material and adopting a secondary sintering mode, so that on one hand, the energy is saved, and on the other hand, the larger particle size can be obtained at a lower sintering temperature, and the dielectric constant is favorably improved; and meanwhile, in the grain boundary insulation process, ZnO is added, and the insulation resistance and the insulation strength of the product are improved.

Description

technical field [0001] The invention relates to the technical field of capacitors, in particular to a high-medium grain boundary layer ceramic material and a preparation method of a grain boundary layer ceramic substrate. Background technique [0002] The miniaturization trend of electronic devices requires capacitors to have smaller dimensions and greater energy storage density, and grain boundary layer ceramics have ultra-high dielectric constants, which meet the requirements of capacitors, and are therefore widely used as dielectric materials for capacitors. [0003] At present, there is still a large gap between domestic R&D and mass production capacity of grain boundary layer ceramic materials with high dielectric constant and similar foreign products. The dielectric constant of foreign related ceramics can reach 10,000-60,000 and has been mass-produced; while domestic similar products are reliable. There is a certain gap between foreign countries in terms of performanc...

AI Technical Summary

Problems solved by technology

[0004] In terms of technology, there are two preparation methods for the preparation of grain boundary layer ceramic substrates: primary sintering and secondary sintering; The reduction and oxidation reactions are completed successively during the heating and cooling process, the process control is difficult, and the product performance stability is poor; the commercially available products are mainly secondary sintering, first high-temperature reduction sintering, and then oxidation heat treatment in the air, the product performance is relatively low. Stable and high reliability, but the reduction and sintering temperature is too high (about 1450°C)

[0005] In summary, the main problems in the preparation of high-mesogenic boundary layer ceramic substrates are the high reduction and sintering temperature, the ceramic substrate is easy to curl, crack, and poor insulation performance; the final product performance consistency, low reliability

Images