KR101153623B1 - Sintering furnace for ceramic product and sinterring mothod using the same - Google Patents

Abstract

According to an embodiment of the present invention, the present invention is a furnace main body having a heat insulator embedded therein, the bottom of the heat insulator is disposed, the setter is a ceramic molded body is stacked on top, the exhaust port disposed on the top of the heat insulating material, the ceramic molded body The present invention provides a firing furnace for ceramic products, and a firing method using the same, including a heating generator disposed at least around and a plasma generator arranged to correspond to the ceramic molded body in which the heating element is not disposed.

According to an embodiment of the present invention, according to the present invention, it is possible to provide a firing furnace for a ceramic product and a firing method using the same, which can prevent the change of characteristics of the ceramic product due to the temperature gradient during firing by minimizing the temperature deviation inside the firing furnace. Can be.

Ceramic products, kiln, plasma, heating element

Description

Sintering furnace for ceramic product and sinterring mothod using the same}

The present invention relates to a firing furnace for ceramic products and a firing method using the same, and more particularly, to a ceramic firing furnace which can prevent the change of characteristics of the ceramic product due to the temperature gradient during firing by minimizing the temperature deviation inside the firing furnace; It relates to a firing method using the same.

In general, ceramic electronic products, such as multilayer ceramic capacitors, ferrites, piezoelectric materials, etc., are formed of a ceramic raw material into a predetermined shape and manufactured into a molded body, and then the multilayer ceramic molded body is manufactured through a binder removal process, a firing process, and a cooling process in a kiln. Is done.

The process for making such ceramic formed body is, BaTiO _3, CaCa _3, MnO, the addition of organic components of the binder to the material powder, such as Glass Frit to prepare a slurry, and a ceramic sheet is formed to a slurry of a dielectric sheet, The laminated sheet is manufactured by laminating a plurality of internal electrodes printed on the surface of the ceramic sheet by pattern-printing internal electrodes, which are metal components of Ag, Ni, Cu, Pd, and Pd / Ag, in a multilayered manner. The ceramic molded body is manufactured by pressing a sheet | seat at the pressure of 500-1300 kgf / cm <2>, and cutting a crimped | laminated sheet | seat to a predetermined length.

In addition, the ceramic molded body is bake-out at a temperature of 230 ° C. to 450 ° C. in a sintering furnace to remove the binder component, and a firing step of firing at a temperature of 800 ° C. to 1300 ° C. for 10 to 24 hours. After the completion of the firing, the cooling step is cooled continuously to a low temperature, and the ceramic molded body fired in the firing furnace is finished with a ceramic product by plating by applying an external electrode and a terminal electrode on the outer circumferential surface thereof.

However, when manufacturing a multilayer ceramic substrate in which an electronic device is embedded according to the prior art, unlike the case of manufacturing a ceramic component in a chip form, the warpage or deformation of the ceramic substrate frequently occurs during the firing process due to the large area of the substrate. It is happening.

There are many causes of the above phenomenon, but in general, the heat flow is not desired in the convection firing method, so the temperature gradient of the upper and lower firing furnaces and the temperature rising rate of the lower part of the kiln are actually higher than the temperature rising rate of the firing furnace. There is a problem that the plastic behavior is changed over the entire ceramic substrate due to the temperature gradient generated because it is later.

The present invention is to solve the above problems, the object of the present invention is It is to provide a firing furnace for ceramic products and a firing method using the same, which can prevent the change in the characteristics of the ceramic material due to the temperature gradient during firing by minimizing the temperature deviation inside the firing furnace.

In order to achieve the above object, one embodiment of the present invention,

A furnace body having a heat insulator embedded therein, a lower body of the heat insulator, a setter having a ceramic molded body stacked thereon, an exhaust port disposed at an upper part of the heat insulating material, a heating element disposed corresponding to a portion around the ceramic molded body, and the Provided is a firing furnace for ceramic products including a plasma generator disposed to correspond to another portion of a ceramic formed body in which a heating element is not disposed.

Here, the plasma generator may be at least one selected from cantal, quartz, and electromagnet.

The heating element may be disposed above the ceramic formed body, and the plasma generator may be disposed below the ceramic formed body.

In addition, the heating element may be disposed below the ceramic formed body, and the plasma generator may be disposed above the ceramic formed body.

In order to achieve the above object, another embodiment of the present invention,

Providing a furnace body in which a heat insulator is embedded, placing a setter under the heat insulator, loading a ceramic molded body on the setter, arranging an exhaust outlet on the top of the heat insulating material, and surrounding the ceramic molded body Arranging at least one heating element corresponding to a portion of the substrate, arranging a plasma generator corresponding to another portion of the ceramic molded body in which the heating element is not disposed, and firing the ceramic molded body. It provides a firing method using.

In this case, the plasma generator may be formed of at least one selected from kanthal, quartz, and electromagnet.

The heating element may be disposed above the ceramic formed body, and the plasma generator may be disposed below the ceramic formed body.

In addition, the heating element may be disposed below the ceramic formed body, and the plasma generator may be disposed above the ceramic formed body.

The firing of the ceramic formed body may include activating the firing step by reflowing an active gas into the heat insulating material through the exhaust port.

Here, the active gas may include at least one selected from argon, helium and nitrogen.

According to the present invention, it is possible to provide a firing furnace for a ceramic product and a firing method using the same, which can prevent a change in characteristics of a ceramic product due to a temperature gradient during firing by minimizing a temperature deviation in the firing furnace.

In addition, by supplying a smooth heat source and inert gas in the kiln, it is possible to manufacture a single crystal ceramic product in which no residual crystal phase is formed at the same time as metal firing without physical and chemical bonding during firing, so that there is little error in dielectric constant, specific resistance, capacitor, etc. In other words, it is also possible to manufacture ceramic products and modules having excellent electrical properties.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

However, embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below. In addition, embodiments of the present invention is provided to those skilled in the art to more fully describe the present invention. Therefore, the shape and size of the elements in the drawings may be exaggerated for clearer explanation, elements represented by the same reference numerals in the drawings are the same elements.

Hereinafter, the firing furnace according to the first and second embodiments of the present invention will be described with reference to FIGS. 1 and 2.

1 is a cross-sectional view schematically showing a furnace for ceramic products according to a first embodiment of the present invention, Figure 2 is a cross-sectional view schematically showing a furnace for ceramic products according to a second embodiment of the present invention.

The firing furnace 1 for a ceramic product according to the first embodiment of the present invention is disposed below the furnace body 10 and the heat insulating material 11 having the heat insulating material 11 therein, and the ceramic molded body C is disposed on the upper portion. Ceramics in which the setters S, the exhaust ports 17 disposed above the heat insulating material 11, at least a portion around the ceramic molded body C are disposed, and the heating elements 13 and the heating elements 13 are not disposed. It is comprised including the plasma generator 15 arrange | positioned corresponding to the other part of the molded object (C).

Meanwhile, the firing furnace 2 for ceramic products according to the second embodiment of the present invention is disposed below the furnace main body 20 and the heat insulating material 21 having the heat insulating material 21 therein, and the ceramic molded body C ′. Is installed on top of the setter (S '), the exhaust port 27 disposed on the upper portion of the heat insulating material 21, the heating element 23 and the heating element 23 disposed corresponding to at least a portion around the ceramic molding (C'). It is configured to include a plasma generator 25 disposed to correspond to the other portion of the ceramic molded body (C ') is not disposed.

The heat insulating material (11, 21) is a wall made of alumina-based ceramic fiber board, the bottom body is composed of a refractory heat insulating material of mullite refractory, a plurality of heating elements (13, 23) through the wall of the heat insulating material (11, 21) As is coupled to the inside of the sealed chamber-type heat insulating material (11, 21) is heated to a temperature of about 800 ℃ ~ 1700 ℃ by heating the heating elements (13, 23). Here, the materials constituting the heat insulating materials 11 and 21 are not limited thereto.

In addition, setters S and S 'having ceramic moldings C and C' loaded thereon are disposed below the insulation 11 and 21, and ceramic moldings C having an upper portion of the insulation 11 and 21. And C '), exhaust ports 17 and 27 are arranged to discharge binders and other impurities including organic substances generated during firing to the outside.

Here, referring to FIG. 1, when the heating element 13 is disposed on the ceramic molded body C, the plasma generator 15 according to the first embodiment of the present invention may be a ceramic in which the heating element 13 is not disposed. It is arranged to correspond to the lower part of the molded body (C).

On the contrary, referring to FIG. 2, when the heating element 23 is disposed below the ceramic molded body C ′, the plasma generator 25 according to the second embodiment of the present invention does not have the heating element 23. It is disposed so as to correspond to the upper portion of the ceramic molded body (C ').

The ceramic molded bodies C and C 'having the heat generating elements 13 and 23 disposed in close proximity to each other have a relatively shorter firing shrinkage than the ceramic molded bodies C and C' having the heat generating elements 13 and 23 disposed relatively far. The plastic shrinkage initiation imbalance with the ceramic moldings C and C 'in which (13, 23) is relatively far apart may cause various deformations such as bending, slack or cracking in the ceramic moldings C and C'. have.

However, as in the embodiment of the present invention, when the plasma generators 15 and 25 are disposed so as to correspond to the ceramic molded bodies C and C 'on which the heating elements 13 and 23 are not disposed, the above-described plastic shrinkage start imbalance. By complementing the above-described deformation that may occur in the ceramic molded bodies (C, C ') can be prevented.

Here, the plasma generators 15 and 25 may be at least one selected from kanthal, quartz and electromagnets, and may be provided in the form of wires or bars, but the plasma generators 15 and 25 may be in the form of a plasma generator. It is not limited to this, and may be in the form of a horseshoe as shown.

Hereinafter, a firing process of a ceramic product using the firing furnace for ceramic products according to the first and second embodiments of the present invention will be described with reference to FIGS. 1 to 3.

1 is a cross-sectional view schematically showing a kiln for ceramic products according to a first embodiment of the present invention, Figure 2 is a cross-sectional view schematically showing a kiln for ceramic products according to a second embodiment of the present invention, Figure 3 It is a flowchart which shows the baking process of a ceramic product using the firing furnace for ceramic products which concerns on 1st Example and 2nd Example of this invention.

The firing method of the ceramic product using the firing furnaces 1 and 2 for ceramic products according to the first and second embodiments of the present invention includes the furnace bodies 10 and 20 having the heat insulating materials 11 and 21 embedded therein. The step of providing, the step of placing the setters (S, S ') in the lower portion of the heat insulating material (11, 21), the step of loading the ceramic molded body (C, C') on the setters (S, S '), the heat insulating material (11) Disposing the exhaust ports 17 and 27 on the upper portion of the 21 and disposing at least one heating element 13 and 23 to correspond to a portion around the ceramic moldings C and C ', Plasma generators 15 and 25 are disposed so as to correspond to the other parts of the ceramic molded bodies C and C 'where 23 is not disposed, and the ceramic molded bodies C and C' are fired.

First, the furnace body 10, 20 in which the wall is composed of an alumina-based ceramic fiber board and the bottom is insulated with the heat insulators 11, 21 composed of a refractory heat insulator of mullite refractory material is provided. Here, the materials constituting the heat insulating materials 11 and 21 are not limited thereto.

As the plurality of heat generating elements 13 and 23 are coupled through the walls of the heat insulating materials 11 and 21, the inside of the sealed chamber-type heat insulating materials 11 and 21 is 800 ° C. to 1700 by heating the heating elements 13 and 23. It is heated up to a temperature of about ℃.

Next, setters S and S 'are disposed below the heat insulating materials 11 and 21, and ceramic molded bodies C and C' are loaded on the setters S and S '.

In addition, the exhaust ports 17 and 27 are disposed on the ceramic molded bodies C and C 'on the upper portions of the heat insulating materials 11 and 21 to discharge binders and other impurities including organic substances generated during firing to the outside.

Here, in the case where the heating element 13 is disposed on the ceramic formed body C (see FIG. 1), the plasma generator 15 according to the first embodiment of the present invention is a ceramic formed body in which the heating element 13 is not disposed. Arrange so as to correspond to the lower part of (C).

On the contrary, in the case where the heating element 23 is disposed below the ceramic molded body C '(see FIG. 2), the plasma generator 25 according to the second embodiment of the present invention may be a ceramic in which the heating element 23 is not disposed. It arrange | positions so that it may correspond to the upper part of the molded object C '.

Finally, the ceramic molded bodies (C, C ') are fired. During firing, the firing step may be activated by reflowing an active gas into the heat insulating materials 11 and 21 through the exhaust ports 17 and 27. Here, the active gas may include at least one selected from argon, helium, and nitrogen, but the active gas is not limited thereto.

The ceramic molded bodies C and C 'having the heat generating elements 13 and 23 disposed in close proximity to each other have a relatively shorter firing shrinkage than the ceramic molded bodies C and C' having the heat generating elements 13 and 23 disposed relatively far. The plastic shrinkage initiation imbalance with the ceramic moldings C and C 'in which (13, 23) is relatively far apart may cause various deformations such as bending, slack or cracking in the ceramic moldings C and C'. have.

However, as in the embodiment of the present invention, when the plasma generators 15 and 25 are disposed so as to correspond to the ceramic molded bodies C and C 'on which the heating elements 13 and 23 are not disposed, the above-described plastic shrinkage start imbalance. By complementing the above-described deformation that may occur in the ceramic molded bodies (C, C ') can be prevented.

Here, the plasma generators 15 and 25 may be made of at least one selected from kanthal, quartz, and electromagnet, and may be provided in a wire or bar form. The shape is not limited thereto, and may be a horseshoe shape as shown.

According to the present invention, it is possible to provide a firing furnace for a ceramic product and a firing method using the same, which can prevent a change in characteristics of a ceramic product due to a temperature gradient during firing by minimizing a temperature deviation in the firing furnace.

In addition, by supplying a smooth heat source and inert gas in the kiln, it is possible to manufacture a single crystal ceramic product in which no residual crystal phase is formed at the same time as metal firing without physical and chemical bonding during firing, so that there is little error in dielectric constant, specific resistance, capacitor, etc. In other words, it is also possible to manufacture ceramic products and modules having excellent electrical properties.

It is possible not only to control the pattern accuracy in the large-area ceramic substrate of the multi-layer thick film for high-precision fine pattern formation, but also to control the shrinkage of the thick film substrate, and to reduce the deformation of the thick film substrate. Simultaneous firing control of the laminate is also possible, so that the delamination between the different laminates can be improved.

It is also possible to control the temperature increase rate of the multilayered large-area thick film ceramic laminate in a large kiln, and thus there is an advantage in that it is possible to freely design a high frequency application module such as signal line, ground, and power.

Simultaneous firing of high-definition fine patterns is possible, so that pattern formation for thin film resistors and inductors can be freed, and high integration of high frequency substrates will be possible.

In addition, since the removal of the binder and the solvent is easy and the plastic crystallization and densification are possible regardless of the vertical position difference of the large substrate, it is possible to manufacture a high strength ceramic product without discoloring the plastic ceramic product.

The present invention is not limited by the above-described embodiments and the accompanying drawings, but is intended to be limited only by the appended claims. It will be apparent to those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. something to do.

1 is a cross-sectional view schematically showing a firing furnace for a ceramic product according to a first embodiment of the present invention.

2 is a cross-sectional view schematically showing a firing furnace for ceramic products according to a second embodiment of the present invention.

3 is a flowchart schematically illustrating a firing process of a ceramic product using a firing furnace for a ceramic product according to a first embodiment of the present invention.

Claims (10)

A furnace body having a heat insulating material embedded therein; A setter disposed under the heat insulating material and having a ceramic molded body stacked thereon; An exhaust port disposed above the insulation; A heating element disposed corresponding to a portion around the ceramic formed body; And A plasma generator disposed to correspond to another portion of the ceramic formed body in which the heating element is not disposed; Firing furnace for ceramic products comprising a. The method of claim 1, The plasma generator is at least one selected from the group consisting of (kanthal), quartz and electromagnet. The method of claim 1, And the heating element is disposed above the ceramic formed body, and the plasma generator is disposed below the ceramic formed body. The method of claim 1, The heating element is disposed under the ceramic formed body, the plasma generator is disposed in the upper portion of the ceramic formed body firing furnace for ceramic products. Providing a furnace body in which insulation is embedded; Disposing a setter under the insulation; Loading a ceramic molded body onto the setter; Disposing an exhaust port on top of the insulation; Disposing at least one heating element corresponding to a portion around the ceramic formed body; Arranging a plasma generator to correspond to another portion of the ceramic formed body in which the heating element is not disposed; And Firing the ceramic compact; Firing method using a firing furnace for a ceramic product comprising a. The method of claim 5, The plasma generator is a firing method using a kiln for ceramic products, characterized in that formed in at least one selected from kanthal (kanthal), quartz and electromagnets. The method of claim 5, The heating element is disposed above the ceramic formed body, and the plasma generator is disposed below the ceramic formed body firing method using a firing furnace for ceramic products. The method of claim 5, And the heating element is disposed under the ceramic formed body, and the plasma generator is disposed above the ceramic formed body. The method of claim 5, Firing the ceramic molded body, And reflowing an active gas into the heat insulating material through the exhaust port to activate the firing step. 10. The method of claim 9, The active gas is a firing method using a kiln for ceramic products, characterized in that at least one selected from argon, helium and nitrogen.

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