JPH0614495B2 - Method for manufacturing laminated electronic component - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a laminated electronic component such as a laminated inductor or a laminated composite component, and more particularly to a method for forming a terminal electrode for external connection. Is.

[Prior art]

Along with demands for miniaturization and thinning of electronic components, multilayer inductors and composite components thereof are being put to practical use after multilayer capacitors. Such a laminated electronic component is one in which a laminated body of a dielectric or magnetic ceramic having a conductor pattern formed therein is formed by printing or a sheet method.

The internal conductor pattern is drawn out to the end face of the laminate, and a terminal electrode for connecting to an external circuit is formed on the end face. The terminal electrode is formed by stacking, dividing, and firing green sheets or the like that form a large number of elements at the same time, and then applying a conductor such as silver and baking.

〔Task〕

However, since firing is performed after the element is divided, the internal conductor is likely to evaporate during firing, and particularly in a laminated inductor having a narrow conductor pattern width, Q decreases due to an increase in resistance.
In severe cases, it may cause wire breakage.

Further, glass frit is mixed in the paste for the terminal electrode and baking is performed, but if the reaction between the glass frit and the laminated body is not sufficient, the strength of the electrode cannot be sufficiently obtained. Also,
The glass layer may be formed on the surface of the terminal electrode.

The present invention solves such a problem, and with a small man-hour,
It is intended to prevent evaporation of the conductor material and form a terminal electrode having sufficient strength.

[Means for Solving the Problems]

The present invention solves the above problem by utilizing glass contained in a ceramic insulator for forming a terminal electrode during firing.

That is, an insulating ceramic paste containing glass and a conductive paste are laminated by printing to form a conductor pattern in the insulator, and the end portion of the conductor pattern is pulled out to the end face of the laminate, and the end face is used for external connection. In a method of manufacturing a laminated electronic component in which terminal electrodes are formed, paste is printed and laminated, then divided into elements, and after barrel polishing these elements, a conductor paste is applied to the end faces of each element to form a laminated body. This is characterized in that the firing of 1) and the firing of the terminal electrode are performed simultaneously.

Further, a conductor paste is printed on an insulator ceramic green sheet containing glass, the sheets are laminated, a conductor pattern is formed in the insulator, and the end portion of the conductor pattern is drawn out to the end face of the laminate body. In a method for manufacturing a laminated electronic component in which terminal electrodes for external connection are formed on end faces, sheets are laminated and then divided into elements, and after barrel polishing these elements, a conductor paste is applied to the end surfaces of each element. It is characterized in that the laminated body and the terminal electrodes are simultaneously fired.

[Action]

Glass such as borosilicate glass added to an insulating ceramic paste or an insulating ceramic green sheet for the purpose of low temperature firing plays the same role as a conventional glass frit. During firing, it is diffused from the inside into the electrode material such as silver applied to the end faces, and firmly adheres the laminated body and the terminal electrode.

The barrel polishing forms a roundness on the end face forming the electrode, and the concentration of stress due to shrinkage during firing can be alleviated.

〔Example〕

 Examples of the present invention will be described below.

An example of forming a laminated inductor by printing and laminating a magnetic paste such as ferrite and a conductor paste containing silver as a main component will be described.

A magnetic paste containing borosilicate glass is printed on a base material such as mylar film to have a predetermined thickness, and a conductive paste is printed thereon for about half a turn. A large number of the same patterns are simultaneously formed on one magnetic wafer.
Next, a magnetic paste is formed so as to cover the other conductor patterns while leaving the ends of the conductor patterns.

A conductor pattern for the next about half a turn is formed with the ends connected.

By repeating this process, the conductor pattern having a predetermined number of turns is formed, and finally the magnetic paste is formed to have a predetermined thickness. As a result, a coil pattern that circulates inside the magnetic body is formed.

Both ends of the conductor pattern that circulates are formed so as to be exposed at the end faces when divided into elements. That is, the first conductor pattern and the last conductor pattern are formed so as to extend to the scribe line. If an intermediate tap or the like is required, that portion also needs to be drawn out to the end face.

After dividing into the elements, the unfired body is polished and shaped by barrel polishing. Then, a conductor paste containing silver as a main component is applied to the exposed end surface of the conductor pattern.
It is advisable to form the conductor paste so that a part thereof is applied to the end face and the face adjacent to the end face.

Then, the element is fired in a firing furnace. Since it is a magnetic ceramic containing glass such as borosilicate glass, it can be fired at a relatively low temperature. A sintered body is obtained by firing at 900 ° C. for several hours. During this firing, the conductor such as silver applied to the end face is also baked at the same time. The above temperature is a sufficient temperature for baking silver or the like.

It was confirmed that the terminal electrode baked in this manner was firmly connected to the laminated body by the glass diffused from the laminated body into the conductor. Moreover, glass did not deposit on the surface of the terminal electrode unless the firing time was too long.

The surface of this silver electrode can be plated with a metal such as copper, nickel or tin, if necessary. Since the surface of the terminal electrode is the metal layer, the electrode material can be easily plated.

The above example is an example in which the paste of the magnetic material and the paste of the conductor are alternately printed, but the magnetic material sheets may be laminated. In that case, the magnetic ceramic green sheet
A slurry of ferrite to which glass such as borosilicate glass is added is formed by a doctor blade method or the like.

It is formed by printing a conductor pattern for each half turn on the surface of the sheet. The ends are connected by through holes formed in the sheet. Similar to the above example, both ends and, if necessary, tap terminals are formed to extend to the scribe line so as to be exposed on the end faces when the elements are divided.

The steps after the division of the element are exactly the same as the above example.

Further, the present invention can be applied not only to the laminated inductor but also to a laminated capacitor or a laminated LC composite component including both of them.
It is also effective for forming electrodes of through holes and terminal electrodes of a multilayer circuit board or the like.

[Effect] According to the present invention, since the step of forming the terminal electrode can be performed simultaneously with the firing of the laminated body, the number of steps can be significantly reduced.

Further, since the exposed end surface of the end portion of the conductor pattern is covered with the conductor and fired, it is possible to prevent evaporation of the inner conductor during firing. This is a particularly advantageous point in a laminated inductor or the like having a thin conductor pattern.

Furthermore, it was confirmed that the strength of the terminal electrode was significantly improved. Not only is the adhesion improved, but plating is also possible, which has the advantage of preventing solder erosion.

Moreover, in the laminated inductor, the lead-out portion is conventionally formed wide to prevent evaporation, but according to the present invention, it may have the same width as the internal pattern. Therefore, the stray capacitance generated between the conductor patterns can be significantly reduced.

Claims (3)

[Claims] 1. An insulating ceramic paste containing glass and a conductive paste are laminated by printing to form a conductive pattern in the insulating body, the end portion of the conductive pattern is drawn out to the end face of the laminated body, and the end face is externally exposed. In a method for manufacturing a laminated electronic component in which terminal electrodes for connection are formed, paste is printed and laminated, then divided into elements, and after barrel polishing these elements, a conductor paste is applied to the end faces of each element. A method for manufacturing a laminated electronic component, comprising simultaneously firing a laminate and a terminal electrode. 2. A conductor paste is printed on an insulating ceramic green sheet containing glass, the sheets are laminated to form a conductor pattern in the insulator, and an end portion of the conductor pattern is drawn out to an end face of the laminate. In the method of manufacturing a laminated electronic component in which terminal electrodes for external connection are formed on the end faces of the laminated electronic components, the sheets are laminated and then divided into elements, and the elements are barrel-polished. Is applied, and the firing of the laminated body and the firing of the terminal electrode are performed at the same time. 3. The conductor paste forming a conductor pattern inside the laminate is mainly composed of silver, and the conductor paste forming the terminal electrode is mainly composed of silver not containing glass. Alternatively, the method for manufacturing a laminated electronic component according to the second aspect.