JPH0360103A - Manufacture of magnetic material for laminated lc compound component - Google Patents

Abstract

PURPOSE:To manufacture the title magnetic body material in the shrinkage factor matched with that of a dielectric material as well as the augmented mechanical strength causing no release, etc., by a method wherein the magnetic body material is composed of a ferrite especially nickel ferrite mixed with borosilicate glass while the ferrite is calcinated in two phases. CONSTITUTION:The permittivity of a ceramic magnetic body is decreased to correspond to high frequency by mixing ferrite with borosilicate glass. Furthermore a ferrite magnetic material is calcinated in two phases so that grains may be made fine and homogenous thereby enabling the matching of shrinkage factor and the stability of electrical properties to be attained. Through these procedures, the mechanical strength can be augmented to enhance the reliability and the production yield.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a method for manufacturing a magnetic material used in a laminated inductor of a laminated LC composite component, and in particular,
The present invention relates to a method for producing a low dielectric constant magnetic material suitable for use in two or more high frequency bands.

[Prior art]

With the demand for thinner and more compact electronic components, the field of inductors has seen an increase in the use of multilayer inductors, which do not use windings but instead have a conductor pattern circulating inside a ferrite magnetic body. It has become. Further, LC composite parts fired integrally with a multilayer capacitor are also used for use in filters and the like.

There are two types of laminated inductors: one in which a conductor pattern is formed on a magnetic ceramic green sheet and then laminated while connecting the conductor patterns, and another in which a magnetic paste of ferrite and a conductor paste such as silver are alternately printed and laminated. . When making an LC composite part, it is fired together with a capacitor laminate with opposing electrodes formed in the dielectric material,
Terminal electrodes are formed and completed.

The laminated inductor of this laminated LC composite component has so far been mainly used in a frequency band of 100 MHz or less, but it is desired that it can also be used in a high frequency region exceeding 100 MHz. For this purpose, magnetic materials to which borosilicate glass is added have been proposed.

〔assignment〕

However, during the firing stage of laminated LC composite parts, there is a difference in the shrinkage rate of the dielectric material in the capacitor part and the magnetic material in the inductor part, which is thought to cause peeling and deterioration of electrical characteristics due to stress. .

The present invention improves the manufacturing method of ferrite material, which is a magnetic material, to provide a magnetic material that matches the shrinkage rate with a dielectric material, does not cause peeling, and has improved mechanical strength. It is.

Moreover, this is intended to stabilize electrical characteristics and the like.

[Means to solve the problem]

The present invention solves the above problems by calcining the ferrite in two stages using a magnetic material in which borosilicate glass is mixed with ferrite, particularly nickel ferrite.

In other words, it is a ceramic magnetic paste for forming a laminated inductor, which is a laminated LC composite component made by integrally firing a capacitor with opposing electrodes formed inside and a laminated inductor with a conductor pattern circulating inside. In the method for manufacturing a magnetic material for laminated LC composite parts, the ceramic magnetic material is made by adding borosilicate glass to ferrite, and after mixing and calcining the ferrite material, the ferrite material and borosilicate glass are mixed. It is characterized by being calcined and then pulverized.

It can be used not only as a printing paste but also as a material for magnetic ceramic green sheets.

[Effect]

By mixing borosilicate glass with ferrite, the dielectric constant of the ceramic magnetic material can be lowered and it can handle high frequencies. Furthermore, by calcining the ferrite magnetic material in two stages, it becomes possible to make the particles finer and more homogeneous, thereby making it possible to match the shrinkage rate and stabilize the electrical characteristics.

〔Example〕

Examples of the present invention will be described below.

As nickel ferrite, FezO3 is 44 molX
, NiO was used at a mixing ratio of 56 molχ. As the borosilicate glass, BO-9 manufactured by Nippon Electric Glass Co., Ltd. was used.

Fetus and NiO, which are the materials of nickel ferrite
The powdered materials were weighed, mixed in a ball mill for about 6 hours, dried, and then calcined at a temperature of about 900'C for 2 hours.

The obtained nickel ferrite powder and borosilicate glass were weighed and mixed in a mixture of 70 wtX and 30 wtX.

Mixing was carried out for approximately 6 hours.

The powder obtained by this mixing was calcined. The calcination temperature was about 700''C and the time was 2 hours.

This sintered body was crushed for 2 to 6 hours to obtain a magnetic material. This pulverization time varies depending on the calcination conditions, and in particular, since the state of the particles varies depending on the temperature, it can be adjusted based on the results.

The particles of the magnetic material obtained by the above manufacturing process are 0.
It was confirmed that the particles were extremely fine, with a particle diameter of about 0.03μ.

A binder is added to this magnetic material to create a magnetic paste, which is printed alternately with a conductive paste containing Ag as a component.
Stack. Thereby, a coil pattern is obtained that connects and circulates from glabella to glabella within the magnetic body.

The laminated magnetic material with a conductive pattern formed therein is dried and then fired. In the laminated LC composite component, a capacitor with opposing conductor patterns is further integrally formed within the dielectric material and integrally fired.

When a magnetic material and a dielectric material are fired together, their shrinkage rates are different, which tends to cause peeling between the eyebrows. In addition, warping occurs, which also causes stress. FIG. 1 is a graph showing the situation. The horizontal axis shows the firing temperature, and the vertical axis shows the shrinkage rate. Titanium-based dielectric material (TiOz 90.45wt
X, Ni06wtχ, Cu03wtX, Mn0zO
, 5wtX, Sing 0.05wtχ) is shown by solid line 11. When the temperature exceeds 650"C, shrinkage occurs, and at 870°C, the shrinkage is about 7.8%. In contrast, the dotted line 12 shows the shrinkage of the conventional magnetic material containing borosilicate glass. be.

The shrinkage started at about 500''C, and at 870''C it was 4.6%, which was a big difference from the dielectric material.

When a magnetic material subjected to two-stage calcination according to the present invention is used, failure wA13 is shown. The change in shrinkage rate approximates the change in the dielectric material, and the difference is within 1%. Therefore, even if the dielectric material and the magnetic material are fired together, their shrinkage rates are matched and no peeling occurs.

〔effect〕

According to the present invention, the contraction rate of the magnetic material can be matched with the contraction rate of the dielectric material, so it is possible to prevent peeling between the eyebrows. This increases mechanical strength, improves reliability, and improves yield.

Further, it is also possible to prevent deterioration of electrical characteristics caused by stress caused by a difference in shrinkage rate.

Furthermore, the characteristics of the laminated inductor and laminated LC composite parts manufactured using the magnetic material manufactured according to the present invention became stable, and variations were reduced, probably due to the finer and more homogenized particles.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the characteristics of the magnetic material according to the present invention.

Claims (2)

[Claims] (1) Ceramic magnetic paste for forming a laminated inductor of a laminated LC composite component made by integrally firing a capacitor with opposing electrodes formed inside and a laminated inductor with a conductor pattern circulating inside. In the method for manufacturing a magnetic material for a laminated LC composite component, the ceramic magnetic material is made by adding borosilicate glass to ferrite, and after mixing and calcining the ferrite material,
A method for producing a magnetic material for laminated LC composite parts, which comprises mixing the ferrite material and borosilicate glass, calcining the mixture, and then pulverizing the mixture. (2) Ceramic magnetic paste for forming a laminated inductor of a laminated LC composite component made by integrally firing a capacitor with opposing electrodes formed inside and a laminated inductor with a conductor pattern circulating inside. In the method for manufacturing a magnetic material for laminated LC composite parts, the ceramic magnetic material is made by adding borosilicate glass to nickel ferrite, and after mixing and calcining the ferrite material, the ferrite material and the borosilicate glass are mixed. A method for producing a magnetic material for laminated LC composite parts, which comprises mixing, calcining, and then pulverizing.