JPH08130107A - Manufacture of ceramic substrate for chip-type electronic component and chip-type electronic component - Google Patents

Abstract

PURPOSE: To provide methods for manufacturing a ceramic substrate for a chip-type electronic component wherein a flat division face is ensured so that there may be no trouble forming side face electrode layers of a chip-type electronic component and for manufacturing a chip-type electronic component. CONSTITUTION: On an unbaked ceramic sheet, a plurality of through hole pairs 2 are formed and nearly-through slits 3 are formed between the through hole pairs and then a plurality of slits 4 are so formed as to cross at right angles with the nearly- through slits 3. After that, this ceramic sheet is heated and baked and thereby a ceramic substrate 1' is obtained. Nextly, a resistor layer 5 and a surface electrode layer 6 are formed for each of unit regions which are partitioned by the nearly-through slits 3 and the slits 4. Then, the resistor layer 5 and the surface electrode layers 6 are trimmed to regulate resistance values and then protection layers 7 to cover the resistor layers 5 are formed. After that, the ceramic substrate 1' is cut along the slits 4' at both remote ends and the nearly-through slits 3 and is divided into bar-like sections. After that, side face electrode layers are formed at both side faces in the longitudinal direction of each bar section and then each bar section is cut along the transverse slits 4 and is divided into chip-type resistors.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a ceramic substrate used for manufacturing chip-shaped electronic components such as chip resistors and chip capacitors, and chip resistors such as chip resistors and chip capacitors using the ceramic substrate. The present invention relates to a method of manufacturing an electronic component.

[0002]

2. Description of the Related Art Conventionally, a ceramic substrate for a chip-shaped electronic component and a chip resistor, which is one of the chip-shaped electronic components using the substrate, are manufactured by the following method, for example.
First, as shown in FIGS. 6 (1) to 6 (3), vertical and horizontal slit grooves 22 and 23 are formed on an unfired ceramic sheet.
Is formed by embossing with a die, and then the unfired ceramic sheet is fired to obtain a ceramic substrate 21. In this case, the slits at both ends of either one of the vertical and horizontal slit grooves 22 and 23 are formed so as to reach the end portion of the ceramic substrate. In addition, vertical and horizontal slit grooves 22, 2
3 may be formed not only on the upper surface of the ceramic substrate but also on a predetermined position on the back surface thereof (see FIG. 6 (4)).

Thereafter, as shown in FIG. 7 (1), a resistor layer 24 and a surface electrode layer 25 are formed in each arbitrary unit area defined by vertical and horizontal slit grooves 22 and 23 on the ceramic substrate 21. After forming, trimming and adjusting the resistance value, a protective layer 26 covering the resistor layer 24 is formed. Then FIG.
As shown in (2), first, the slit grooves 22 and 23 in the vertical and horizontal directions are formed.
After dividing the substrate along the grooves on both ends of each of the above, the ceramic substrate 21 is divided into plural pieces along the slit groove 22 on the side where the surface electrode layer 25 is formed as shown in FIG. 21 '. Then, as shown in FIG. 8 (2), the side surface electrode layers 27 are formed on both side surfaces in the longitudinal direction of the rod-shaped piece 21 '.
Is formed, and finally, the rod-shaped piece 21 ′ is divided along the lateral slit groove 23 to obtain a chip shape.

However, according to the above method, when the ceramic substrate 21 is divided into the rod-shaped pieces 21 'along the slit groove 22 on the side where the surface electrode layer 25 is formed, the side surfaces of the rod-shaped pieces 21' are not divided flatly. The problem arises. This is because the portion 22 'other than where the slit groove 22 is formed must be divided by breaking the ceramic substrate. For example, the slit groove 22
When the ceramic substrate formed only on the upper surface is divided, as shown in FIG. 9A, not only the divided side surface 22 ′ becomes flat but also the side opposite to the side where the slit groove 22 is formed is formed. Burrs 28 and chips 28 'may occur at the ends. Even in the case of the ceramic substrate having the slit grooves 22 formed on both sides, the portion 22 'where the slit grooves are not formed is not flatly divided as shown in FIG. 9B. If the divided surface is not flat, the adhesion at the time of forming the side surface electrode layer becomes poor, and the side surface electrode layer cannot be formed, or the side surface electrode layer once formed is peeled off, and the appearance is poor. Problem arises.

In order to solve such a problem, it is desirable that the slit groove 22 on the side where the side surface electrode layer is formed be formed as deep as possible in advance to secure a flat division surface. Most preferably, Japanese Patent Application No. 5-2825
No. 62, and as shown in FIG.
It is preferable that the slit 2a is a penetrating slit 22a that extends from the front surface to the back surface of the ceramic substrate.

[0006]

However, in the case of forming the substantially penetrating slit 22a as described above, the following another problem occurs. In this case, the substantially through slit 22a is formed by pressing the die. That is, as shown in FIG. 11 (1), the blade portion 31 of the die for forming the substantially penetrating slit 22a is pressed from the upper surface of the unfired ceramic sheet 21 ″ to form the substantially penetrating slit 22a. At this time, the blade portion 31 of the die for forming the through slit 22a substantially penetrates from the front surface to the back surface of the unfired ceramic sheet 21 ″, but the force due to the pressing of the blade portion 31 of the die at this time. Also works toward the end 21a of the ceramic sheet, and as a result, as shown in FIG. 11B, from the end 22a 'of the substantially through slit 22a to be originally formed to the part 21a of the unfired ceramic sheet. Internal strain 40 may occur toward the. Unfired ceramic sheet 21 "in this state
When is fired, the substrate is cracked at a portion where the internal strain 40 is generated and the substrate is broken. Further, even if the substrate does not break during firing, the resulting ceramic substrate has a very weak strength, and there is a problem that the substrate breaks during the process of manufacturing a chip resistor from the substrate. .

It is a technical object of the present invention to provide a ceramic substrate for a chip-shaped electronic component and a method for manufacturing a chip-shaped electronic component, which can solve these problems.

[0008]

In order to solve the above technical problems, the present invention takes the following technical measures. That is, the method for manufacturing a ceramic substrate for a chip-shaped electronic component according to claim 1 of the present application includes a step of providing a plurality of a pair of through holes facing each other on an unfired ceramic sheet, and a step of substantially penetrating between the pair of through holes. The method is characterized by including a step of providing slits, a step of providing a plurality of slit grooves orthogonal to the slits that are substantially penetrating, and a step of firing the unfired ceramic sheet to form a ceramic substrate.

Further, in the method of manufacturing the chip-shaped electronic component according to claim 2 of the present application, any of the substantially slits and the slit grooves formed on the ceramic substrate manufactured by the method of claim 1 is used. For each unit area of
A step of forming at least one passive element layer and a surface electrode layer, a step of dividing the ceramic substrate along the substantially penetrating slit, and a step of providing a side surface electrode portion on a division surface by the division. Is characterized by.

By taking the above-mentioned means, according to the invention of claim 1, when the through-slit is formed by pressing the unfired ceramic sheet with the die, the both ends of the through-slit are provided. Since the through hole is provided, the stress due to the pressing of the die blade portion is absorbed by the through hole, and as a result, internal strain does not occur on the ceramic substrate end side from the through hole.

Therefore, according to the present invention, it is possible to prevent the ceramic substrate from cracking during firing of the ceramic sheet or during the manufacturing process, and to obtain a ceramic substrate having a required minimum strength. Moreover, when an electronic component is manufactured using such a ceramic substrate, the problem that the substrate is cracked during the manufacturing process does not occur. Moreover, since the side surface of the substrate on which the side surface electrode layer is to be formed is substantially a through slit in advance, burrs and chips are not generated on the side surface of the substrate when the substrate is divided, and an electronic component with excellent quality can be manufactured. .

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described below with reference to the drawings. First, as shown in FIG. 1 (1), a plurality of pairs of through holes 2 facing the unsintered ceramic sheet 1 are provided, and then, as shown in FIG. 1 (2), through slits are provided between the through holes 2. 3 is formed by pressing the die. At this time, as shown in FIG. 1 (3), the substantially penetrating slit 3 is provided with the blade portion 15 'of the mold 15 so as to substantially reach the back surface from the front surface of the unfired ceramic sheet 1. It may be formed by pressing from above or vice versa. Furthermore, as shown in FIG. 1 (4),
Alternatively, the blade portion 15 ′ of the upper die 15 and the blade portion 16 ′ of the lower die 16 may be pressed against both the upper surface and the back surface of the unfired ceramic sheet 1. In this case, in order to prevent wear and chipping of the blade of the mold, the slit 3 is not completely penetrated, but a part 1a of the unfired ceramic sheet is left over so as to be substantially penetrated. To form.

Next, also by pressing the die, a slit groove 4 is formed in a direction orthogonal to the substantially penetrating slit 3, and then the unfired ceramic sheet 1 is heated and fired, A ceramic substrate 1'as shown in 2 is obtained.
At this time, the grooves 4'at both ends of the slit groove 4 are formed so as to reach the ends of the ceramic substrate. In addition, in the present embodiment, an example in which the through hole 2, the substantially through slit 3, and the slit groove 4 are formed in this order is shown, but the order is not limited to this order, and the slit groove 4, the through hole 2, Method of forming through slit 3 in order, through hole 2, slit groove 4,
A method of forming the substantially through slits 3 in this order, or a method of simultaneously forming the substantially through slits 3 and the slit grooves 4 may be used. Further, when forming the substantially through slit 3 and the slit groove 4, the margin portions 3a and 4a are secured so that the strength of the ceramic substrate 1'is maintained within the minimum required range.

Next, as shown in FIG. 3 (1), the resistance is set for each arbitrary unit area defined by the substantially through slit 3 and the slit groove 4 on the ceramic substrate 1'formed by the above method. After the body layer 5 and the surface electrode layer 6 are formed and trimmed to adjust the resistance value, the protective layer 7 that covers the resistor layer 5 is formed. Then, as shown in FIG. 3 (2), the ceramic substrate 1'is formed into a plurality of rod-shaped pieces 1 "along the slit grooves 4'at both ends and each of the substantially through slits 3, and as shown in FIG. 4 (1). Then, the side surface electrode layers 8 are formed on both side surfaces in the longitudinal direction of the rod-shaped piece 1 ″, and finally divided along the lateral slit groove 4 of the rod-shaped piece 1 ″ into chip-shaped resistors as shown in FIG.

In the above embodiment, the method of manufacturing a single chip resistor has been described, but it is also possible to manufacture a network type resistor as shown in FIG. Figure 5
The reference numerals attached to indicate the same relationships as the reference numerals attached to the above-described embodiments. However, reference numeral 9 in FIG. 5 is a surface electrode which is adjacent to each other when the plurality of resistor layers 5 and the surface electrode layer 6 are formed in each arbitrary unit region partitioned by the substantially through slit 3 and the slit groove 4. This is a through hole provided to prevent the layer 6 from being short-circuited.

As described above, according to the present invention, it is possible to obtain the ceramic substrate for the chip-shaped electronic component having the substantially penetrating slit in which the necessary minimum strength is maintained. Further, by using such a ceramic substrate, it is possible to secure a flat substrate dividing surface, and as a result, a high quality chip that does not cause problems such as defective formation of side electrode layers, peeling of side electrode layers, or defective appearance. It becomes possible to obtain the electronic components.

The present invention is not particularly limited to the configurations such as the shapes and materials described above.

[Brief description of drawings]

FIG. 1 is a partial process diagram illustrating a first embodiment of the present invention.

FIG. 2 is a partial process diagram that follows the process of FIG. 1 for explaining the first embodiment of the present invention.

FIG. 3 is a partial process diagram that follows the process of FIG. 2 for explaining the first embodiment of the present invention.

FIG. 4 is a partial process diagram that follows the process of FIG. 3 for explaining the first embodiment of the present invention.

FIG. 5 is a diagram showing a part of a second embodiment of the present invention.

FIG. 6 is a partial process diagram showing a conventional example.

FIG. 7 is a partial process diagram following the process of FIG. 6 showing a conventional example.

FIG. 8 is a partial process diagram that follows the process of FIG. 7 showing a conventional example.

FIG. 9 is a cross-sectional view of a rod-shaped piece of a ceramic substrate manufactured by a conventional method.

FIG. 10 is a cross-sectional view showing a conventional unfired ceramic sheet.

FIG. 11 is an explanatory view showing a conventional mold and unfired ceramic sheet.

[Explanation of symbols]

 1 Unfired Ceramic Sheet 1'Ceramic Substrate 1 "Ceramic Substrate Rod 2 Through Hole 3 Substantially Through Slit 4 Slit Groove 5 Resistor Layer 6 Surface Electrode Layer 7 Protective Layer 8 Side Electrode Layer

Claims (2)

[Claims] 1. A step of forming a plurality of pairs of through holes facing each other in an unfired ceramic sheet, a step of forming a slit of a substantially penetrating hole between the pair of through holes, and a plurality of slits orthogonal to the slit of the substantially penetrating hole. A method of manufacturing a ceramic substrate for a chip-shaped electronic component, comprising: a step of providing a groove; and a step of firing the unfired ceramic sheet to form a ceramic substrate. 2. At least one passive element layer and a surface electrode for each unit area defined by the slit and the slit groove on the ceramic substrate manufactured by the method according to claim 1. Forming a layer,
A method for manufacturing a chip-shaped electronic component, comprising: a step of dividing the ceramic substrate along the substantially penetrating slit; and a step of providing a side surface electrode layer on a division surface obtained by the division.