Ceramic capacitor made of novel dielectric ceramic composition and manufacturing method thereof

Abstract

The invention discloses a ceramic capacitor prepared from a novel dielectric ceramic composition and a manufacturing method. The ceramic capacitor comprises matrix powder and auxiliary components based on the matrix powder, comprising the following steps that A, firstly, matrix powder and auxiliary components are ground and pre-dispersed, D90 is smaller than 1 micron, finally, the matrix powder and the auxiliary components are fully mixed, ground and dispersed, and (D90-D10) / D50 is smaller than 1, so that the auxiliary components and the matrix powder are fully dispersed and coated, and a uniform and complete core-shell structure is formed; b, the multilayer ceramic capacitor is preliminarily manufactured through air atmosphere plastic removal, the high temperature is lower than 300 DEG C, and the heat preservation time is longer than or equal to 5 h; and C, sintering the multilayer ceramic capacitor in an N2-H2-H2O atmosphere, controlling the highest sintering temperature to be 1220-1300 DEG C, keeping the temperature for 2 hours, then cooling to 1100 DEG C, and keeping the temperature for more than or equal to 2 hours. The cable has ultrahigh normal-temperature and high-temperature insulation resistance, keeps an ultra-long service life at a high temperature, can be applied to various harsh conditions, and ensures the stability and high reliability of product performance.

Description

technical field [0001] The invention relates to the technical field of ceramic capacitors, in particular to a ceramic capacitor made of a novel dielectric ceramic composition and a manufacturing method thereof. Background technique [0002] In recent years, with the development of electronic devices in the direction of integration, functionality, high reliability and low cost, especially the arrival of the future 5G intelligent era, and the future development direction of the military field, the working conditions of multilayer ceramic capacitors have become increasingly severe. Therefore, it is urgent to reduce loss, improve insulation, especially the insulation characteristics under high temperature and high pressure conditions, and improve its dielectric strength to ensure its high reliability and stability under various complex environmental conditions; at the same time, multilayer ceramic capacitors Continuously developing towards the direction of large capacity and thi...

AI Technical Summary

Problems solved by technology

[0003] At present, most of the multilayer ceramic capacitors with nickel electrode technology on the market maintain high insulation resistance at room temperature, but at high temperature (≥125°C) or high pressure, insulation resistance will appear as time increases. The sharp drop of the leakage current and the exponential increase of the leakage current lead to the rapid heating of the product and early short-circuit failure, which cannot meet the performance and life requirements of high-reliability products.

This is mainly because multilayer ceramic capacitors using nickel electrode technology, on the one hand, in order to prevent the oxidation of nickel electrodes, must be re-sintered in a reducing atmosphere, and sintered in a reducing atmosphere, the existing anti-reduction dielectric composition and process, There are still various weakly bound oxygen vacancies and electrons and other carriers inside the product. Under high pressure and high temperature, they are easy to obtain energy and undergo transitions to form conductive particles; With the reduction of barrier, the migration path of conductive particles is shortened. Therefore, when the temperature rises, the excited conductive particles are more likely to migrate to the electrodes at both ends, resulting in an increase in leakage current and a decrease in the insulation resistance of the product, resulting in failure.

According to existing literature reports, although CN1072831 (multilayer ceramic capacitor) also has a relatively high insulation resistance, its high-temperature life (15kV / mm, 150°C) does not exceed 230 hours, and its overall performance is still weak.

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