JPH10107437A - Manufacturing method of circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a circuit board with smaller warp produced in a baking step. SOLUTION: In a method for manufacturing a circuit board, wherein a conductor film to become an internal wiring conductor and a conductor to become a viahole conductor are formed on a glass-ceramic sheet having a circuit board region 101, from which a plurality of circuit boards can be extracted. In a trimmed edge region 102 surrounding the circuit region 101, baking is carried out and then the circuit board region 101 and the trimmed edge region 102 are separated from each other. A dummy viahole conductor 103, having land electrodes 104 whose spacing being 0.1-0.3mm, is formed through the trimmed edge region 102 in the thickness direction thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a circuit board which can be fired at a low temperature, for example, 800 to 1050.degree.

[0002]

2. Description of the Related Art Conventionally, a firing temperature of 800 to 1050 has been used.
There has been proposed a circuit board using a material that can be fired at a relatively low temperature of ° C.

A circuit board which can be fired at a low temperature uses a mixture of crystallized glass powder and ceramic powder as a material of a dielectric (insulating) layer constituting a laminated body, and uses an internal wiring conductor, a via hole conductor, and a surface wiring. A for conductor material used as conductor
g or the like was used.

[0004] Structurally, internal wiring conductors are arranged between dielectric (insulating) layers made of glass-ceramic.
At the same time, via-hole conductors for connecting predetermined internal wiring conductors are arranged in the thickness direction of each layer.
A chip component such as a C chip is mounted, and a surface wiring conductor forming a predetermined wiring is formed.

[0005] In a circuit board having such a structure, the internal wiring conductor is an Ag-based conductor film, so that high-speed circuit can be achieved. Further, as the surface wiring conductor, an Ag-based or Au-based conductor film has been used since it is integrally fired with the laminate.

Then, an IC chip is provided on the surface of the circuit board.
Chip-shaped electronic components are mounted, and the circuit board is mounted on a large-sized printed wiring board by soldering.

As a method of manufacturing such a circuit board, a method is used in which a large-sized glass-ceramic sheet having a shape from which a plurality of circuit boards can be extracted is multilayered.

A through hole serving as a via hole conductor is formed in a region (circuit board region) of the first glass-ceramic sheet serving as a surface dielectric layer of the laminate, which serves as a circuit board, and an Ag-based conductive material is formed in the through hole. Printing and filling with conductive paste,
At the same time, a conductor film serving as a surface wiring conductor is formed by printing with, for example, an Ag-based conductive paste.

A through-hole serving as a via-hole conductor is formed in the circuit board region of the plurality of second glass-ceramic sheets other than the surface dielectric layer, if necessary, and an Ag-based conductive paste is formed in the through-hole. , And at the same time, a conductive film serving as an internal wiring conductor is formed by printing with, for example, an Ag-based conductive paste.

[0010] Such first and second glass-ceramic sheets are positioned and laminated to form a large laminate.

[0011] After that, a division groove for dividing the circuit board region is formed as necessary, and baked.

By this firing, a sintered large circuit board having a plurality of circuit board areas is achieved.

[0013] Thereafter, the substrate is divided into the shapes of the respective circuit boards by dividing or cutting along the dividing grooves.

[0014]

In the above-mentioned method of manufacturing a circuit board, for example, in order to increase the conductivity of the conductor, the ratio of the metal component in the conductive paste is increased, and the sintering of the conductor is started. The temperature (onset of sintering shrinkage) tends to decrease, for example, extremely below 500 ° C. On the other hand, the sintering start (sintering shrinkage) temperature of the laminate (glass-ceramic layer) is set to 600 ° C. or higher. The sintering start temperature of this laminate of 600 ° C. or more is
It is set so that the organic vehicle component in the laminate can be completely removed in the binder removal step which is the first step of the firing.

Due to the gap between the sintering start temperature of the laminated body and the sintering start temperature of each conductor, for example, when the sintering of the laminated body is started, the sintering reaction of the conductor has already started, and a certain strength is obtained. Has been achieved. As a result, in a large circuit board from which a plurality of circuit boards can be extracted, the shrinkage behavior caused by the sintering behavior in the portion where the internal wiring conductor is formed and the portion where the internal wiring conductor is not formed is different, for example, finally discarded In the vicinity of the discarded ear region, a large warp deformation occurs. As described above, the circuit board having a large warp deformation has
Even when trying to mount a C chip or chip-shaped electronic component, it cannot be mounted and connected stably, or when trying to mount a circuit board on a printed wiring board by soldering, it cannot be mounted stably. In addition, cracks may occur on the circuit board due to thermal shock.

The present invention has been devised in view of the above-described problems, and has as its object to prevent large warpage deformation of each of the fired large circuit boards and to improve the mounting reliability of components. An object of the present invention is to provide a method of manufacturing a circuit board which can improve the reliability of mounting on a printed wiring board while improving the circuit board.

[0017]

SUMMARY OF THE INVENTION The present invention is directed to a conductor film having a circuit board region from which a plurality of circuit boards can be extracted, a discarded ear region around the circuit board region, and an internal wiring conductor. And / or stacking and firing a plurality of glass-ceramic sheets on which conductors serving as via-hole conductors are attached, to obtain a large circuit board, and dividing the large circuit board for each circuit board to form a plurality of circuits. In the method of manufacturing a circuit board for forming a substrate, each of the glass-ceramic sheets may have a plurality of dummy via-hole conductors having land electrodes formed at intervals of 0.1 to 0.3 mm in the discard ear region. A method for manufacturing a circuit board, which is a feature of the present invention.

[0018]

According to the present invention, dummy via-hole conductors penetrating in the thickness direction having land electrodes are formed at intervals of 0.1 to 0.3 mm in the abandoned ear region present on the outer periphery of a large-sized circuit board.

In this way, even in the discarded ear region, in the firing step, at the sintering start temperature of the laminate, a dummy penetrating in the thickness direction having a land electrode which starts sintering simultaneously with the internal wiring and via hole conductor of each circuit board region. Since the via hole conductor is formed, the sintering behavior can be made substantially the same as each circuit board region. That is, when a certain degree of strength is obtained by the conductor during the sintering behavior in the circuit board region, the dummy via hole conductor penetrating in the thickness direction having the land electrode also in the abandoned ear region is in the same state,
The mechanical rigidity in the abandoned ear region is increased, and warpage due to a difference in sintering behavior is prevented.

Since dummy via-hole conductors penetrating the thickness of the laminate are formed at intervals of 0.1 to 0.3 mm in the discarded ear area, the mechanical rigidity that can penetrate the thickness of the laminate is reduced. In other words, the warpage generated on the surface of the laminate is suppressed indirectly.

If the distance is less than 0.1 mm, the gap between the dummy via-hole conductors approaches each other, and when a through-hole is formed in the glass-ceramic sheet, a crack is formed between the through-holes. Is dropped, and it is impossible to perform a predetermined printing process for the internal wiring conductor and the like.

On the other hand, if the interval exceeds 0.3 mm, sufficient mechanical rigidity in the discarded ear region cannot be obtained, and a sufficient effect of preventing warpage cannot be obtained.

Also, land electrodes of the dummy via hole conductor are formed between the respective layers. This is formed planarly between each layer. For this reason, the warpage generated on the surface of the laminate is directly suppressed.

Therefore, the dummy via-hole conductors in the thickness direction formed in the discard ear region of the laminate and the land electrodes extending in a plane between the respective layers in the discard ear region of the laminate are formed.
Warp deformation in the discarded ear area is prevented. This allows
A large circuit board close to the abandoned ear area can significantly reduce the warpage of the outer periphery of the circuit board, improving the mounting reliability when mounting IC chips and chip-shaped electronic components on the surface of the circuit board. In addition, even when mounted on a printed wiring board, the circuit board can improve the mounting reliability.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method for manufacturing a circuit board according to the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of a circuit board according to the present invention.

In FIG. 1, reference numeral 10 denotes a circuit board,
Denotes a substrate (hereinafter, referred to as a laminate), 2 denotes a surface wiring conductor formed on the surface of the laminate 1, 3 denotes an internal wiring conductor formed in the laminate 1, and 4 denotes a via hole conductor formed in the laminate 1. Reference numerals 5 and 5 denote IC chip components and electronic components mounted on the surface of the laminate 1.

The laminate 1 has glass-ceramic layers 1a to 1a.
An internal wiring conductor 3 for achieving a predetermined circuit network and generating a capacitance component is arranged between each of the layers 1e and the glass-ceramic layers 1a to 1e. Further, via-hole conductors 4 are formed in the glass-ceramic layers 1a to 1e so as to extend through the thickness direction of the layers.

The glass-ceramic layers 1a to 1e are made of a glass-ceramic material which can be fired at a relatively low temperature, for example, about 850 to 1050 ° C. Specific examples of the ceramic material include cristobalite, quartz, corundum (α-alumina), mullite, and cordierite. In addition, by firing a glass frit containing a plurality of metal oxides as a glass material, at least one kind of crystal of cordierite, mullite, anorthite, Celsian, spinel, garnite, willemite, dolomite, petalite or a substituted derivative thereof is obtained. Is deposited. This glass-ceramic layer 1a-1
The thickness of e is, for example, about 100 to 300 μm.

The internal wiring conductor 3 and the via hole conductor 4
The internal wiring conductor 3 is made of a conductor film (conductor) such as g-based (Ag alone, Ag alloy such as Ag-Pd), and has a thickness of 8 to 15
The diameter of the via-hole conductor 4 can be set to an arbitrary value. For example, the diameter is 80 to 250 μm.

The surface wiring conductor 2 is formed on the surface of the laminate 1. The surface wiring conductor 2 is made of an Ag (Ag)
It is composed of a simple substance, an Ag alloy such as Ag-Pd, or an Au-based (Au simple substance, an Au alloy such as Au-Pd, Au-Pt) conductive film.

The surface wiring conductor 2 mainly constitutes a circuit wiring on the surface, and also has an electronic component 5 joined via solder.
, Or a terminal electrode of a thick film resistor film or a thick film capacitor element. In particular, it is connected to the via-hole conductor 4 exposed from the glass-ceramic layer 1a. Further, it is used as a connection pad (wire bonding pad) of the IC chip 5 connected by the bonding thin wire.

Here, in particular, when an Au-based conductor is used for the surface wiring conductor 2, it is necessary to pay particular attention to the connection with the Ag-based conductor (for example, via-hole conductor 4).

Such a circuit board is made of a large circuit board shown in FIG. 2 in consideration of productivity.

FIG. 2 is a cross section of a portion of the large-sized substrate 100, and FIG. 3 is a partial plan view of the circuit region 101 in which the surface wiring conductors 2 are omitted.

The large circuit board 100 includes a plurality of circuit boards 1
It comprises a circuit board area 101 in which 0s are arranged, and a discard ear area 102 on the outer periphery of the area.

The large-sized circuit board 100 is structurally divided into grooves 110 for dividing the plurality of circuit boards 10 as necessary.
Are formed. When the circuit board 10 is separated by cutting or the like, no division grooves are formed.

In particular, a plurality of dummy via-hole conductors 103 irrelevant to the final circuit wiring are provided in the thickness direction of the abandoned ear region 102 located on the outer peripheral portion of the large-sized circuit board 100.
Is provided around. Plural dummy via-hole conductors 103
Are formed so as to go around the discard ear region 102 once. In addition, in FIG. 3, it is formed so as to make a single round, but it may be made to double or triple.

A land electrode 104 having a size larger than that of the dummy via-hole conductor 103 having a diameter of 200 μm is formed between the glass-ceramic layers intersecting the dummy via-hole conductor 103.
This land electrode 104 may be combined with an adjacent land electrode 104 to form a series of land electrodes.

As described above, the dummy ear hole conductor 103 formed in the thickness direction of the discarded ear region 102 and the land electrode 104 formed between the layers effectively prevent the warp deformation generated during the manufacturing process. Can be prevented. That is, with respect to the stress acting in the thickness direction to cause the warp deformation by the dummy via-hole conductor 103,
Acts to cancel the stress in the thickness direction, and in the case of the land and the land electrode, acts to cancel the stress acting in the thickness direction and the plane direction that is likely to cause warpage deformation, and is discarded as a whole This is to prevent warpage deformation in the ear region.

Next, a method for manufacturing a large circuit board will be described.

First, a circuit board area 101 from which a plurality of circuit boards can be extracted, and a discard ear area 10 formed around the circuit board area 101.
2 and a large-sized glass-ceramic green sheet made of a glass-ceramic material to be the glass-ceramic layers 1a to 1e. Specifically, a ceramic powder, a frit of a low-melting glass component, an organic binder, and a slurry obtained by homogeneously kneading an organic solvent are tape-formed to a predetermined thickness by a doctor blade method, and cut into a predetermined size to form a sheet. .

The ceramic powder includes insulating ceramic materials such as cristobalite, quartz, corundum (α-alumina), mullite, cordierite, BaTiO ₃ , Pb ₄ F
e ₂ Nb ₂ O _12, the dielectric ceramic material, such as TiO _2, Ni-Zn ferrite, (referred to ceramic in a broad sense) Mn-Zn ferrite Do to as magnetic ceramic material can be mentioned, its average particle size 1 0.0-6.0μ
m, preferably 1.5 to 4.0 μm. Note that two or more ceramic materials may be used in combination. In particular, the use of corundum is advantageous in terms of cost.

The frit of the low melting glass component precipitates a crystal phase of cordierite, mullite, anorthite, serdian, spinel, garnite, willemite, dolomite, petalite or a substituted derivative thereof, or a crystal phase having a spinel structure by firing. Any material may be used, for example, glass frit containing B ₂ O ₃ , SiO ₂ , Al ₂ O ₃ , ZnO, and alkaline earth oxide.

The composition ratio between the ceramic material and the glass material is 10 to 60 wt%, preferably 30 to 50 wt%, for firing at a relatively low temperature of 850 to 1050 ° C. 90-40w
t%, preferably 70 to 50 wt%.

It is necessary to give importance to the wettability of the organic binder with solids (ceramic powder, frit of a low melting point glass component). Excellent ones are preferable, and ethylenically unsaturated compounds having a carboxyl group and an alcoholic hydroxyl group such as acrylic acid or methacrylic acid-based polymers are preferable.

As the solvent, an organic solvent or an aqueous solvent can be used. For example, in the case of an organic solvent, 2.
For example, 2.4-trimethyl-1.3-pentadiol monoisoventilate is used. In the case of an aqueous solvent, it must be water-soluble, and a hydrophilic functional group such as carboxyl is contained in the monomer and the binder. A group has been added.

The addition amount is from 2 to 300, preferably from 5 to 100, in terms of acid value. If the added amount is small, the solubility in water, the dispersibility of the powder of the fixed component becomes poor,
When the amount is large, the thermal decomposability deteriorates. Therefore, the addition amount is appropriately added in the above range in consideration of solubility in water, dispersibility, and thermal decomposability.

Next, a through hole serving as a dummy via-hole conductor 103 is formed by punching in the circuit board region 101 of each green sheet to be the glass-ceramic layers 1a to 1e, and a dummy via-hole conductor 103 is provided in the discard ear region 102. Is formed by punching. At this time, the gap between the through holes serving as the dummy via-hole conductors 103 is formed to be 0.1 to 0.3 mm.

Next, the circuit board area 1 of each green sheet
01, the conductors to be the via-hole conductors 4 and the dummy via-hole conductors 103 in the through holes formed in the discard ear region 102
A conductive film to be the land electrode 104 is formed in the discard ear region 102 by printing and drying the Ag-based conductive paste.

In particular, a conductor film serving as the internal wiring conductor 3 is formed on the circuit board region 101 of the green sheet serving as the glass-ceramic layers 1b to 1e by printing and drying an Ag-based conductive paste. Further, a conductor film to be the surface wiring conductor 2 is formed on the circuit board region 101 of the green sheet to be the glass-ceramic layer 1a by printing and drying an Ag-based conductive paste.

Printing and filling of a conductive paste for forming the conductors to be the via-hole conductors 4 and 103 and printing of a conductive paste for forming the conductive films to be the wiring conductors 2 and 3 or the land electrodes 104. May be performed in the same step.

Here, the Ag-based conductive paste of the via-hole conductor 4 and the internal wiring conductor 3 is made of Ag-based (Ag alone, Ag-based).
-Ag alloys such as Pd), borosilicate low melting point glass frit, organic binders such as ethylcellulose, and a homogeneous mixture of solvents are used. The Ag-based conductive paste of the surface wiring conductor 2 is an Ag-based paste (Ag alone, A
Ag alloy powder such as g-Pd), Pt powder, low melting point glass frit, organic binder, and solvent are homogeneously mixed.

As described above, the conductor serving as the via-hole conductor 4 and the conductor film serving as the internal wiring conductor 3 are formed in the circuit board region 101, and the conductor serving as the dummy via-hole conductor 103 and the conductor serving as the land electrode 104 are formed in the discard ear region 102. A green sheet that becomes the glass-ceramic layers 1b to 1e on which the film is formed and an Ag-based conductor film that becomes the surface wiring conductor 2 and a green sheet that becomes the glass-ceramic layer 1a are formed into a laminate 1
Are laminated according to the lamination order of the glass-ceramic layers 1a to 1e described above, and integrated by pressure bonding or the like to form a large laminated substrate.
After that, if necessary, a division groove 110 that divides the circuit board area 101 and the discard ear area 102 and divides the circuit board area 101 into a plurality of circuit boards 10 is formed.

Next, the unfired large laminated substrate is fired in an oxidizing atmosphere or an air atmosphere. The firing step includes a binder removal step and a sintering step.

In the binder removal process, green sheets serving as the glass-ceramic layers 1a to 1e, a conductor film serving as the internal wiring conductor 3, a conductor film serving as the land electrode 104, a conductor serving as the via hole conductor 4, and a dummy via hole conductor 103 are provided. The purpose is to burn off organic components contained in the conductor film serving as the conductor and the surface wiring conductor 2. For example, 500 to 600
It is performed in a temperature range of ° C.

In the sintering process, the glass component of the glass-ceramic green sheet is crystallized and simultaneously dispersed uniformly at the grain boundaries of the ceramic powder to give a certain strength to the laminated body to form the internal wiring conductor 3. Conductor film, land electrode 1
The conductive film No. 04, the via hole conductor 4, the dummy via hole conductor 103, the conductive film metal powder and the Ag powder of the conductive material of the surface wiring conductor 2 are grown by grain growth to reduce the resistance. -Ceramic layers 1a to 1e
Is to be integrated. This is a peak temperature of 850
It is carried out until it reaches に 1050 ° C.

At this time, at a temperature (for example, 550 ° C.) lower than the temperature (about 600 ° C.) at which the glass-ceramic material starts the sintering reaction (sintering shrinkage), the metal powder of the conductive material is turned (sintering shrinkage). Will start.

As a result, the internal wiring conductor 3 and the via-hole conductor 4 are formed inside the circuit board area 101 as shown in FIG. 2, and the surface wiring conductor 2 is formed on the surface. A large-sized circuit board on which the electrode 104 and the dummy via-hole conductor 103 penetrating the thickness are formed is achieved.

Thereafter, if necessary, a thick-film resistance element connected to the surface wiring conductor 2 and an insulating protective film of a predetermined shape are formed, and various electronic components 6 are joined and mounted by soldering or the like. Further, the chip-shaped electronic component 5 is also mounted on the IC chip on the predetermined wiring conductor film, and the IC chip and the surface wiring conductor 2 are joined.

Finally, a dividing process is performed along the dividing groove for dividing each circuit board, and the circuit board 10 shown in FIG. 1 is achieved. When the dividing groove is not formed, cutting and separation are performed for each circuit board region 101 by cutting or the like. Further, the mounting of the electronic components 5 and the like may be divided and cut so as to be in the state of each circuit board 10 and then mounted and joined.

In the above firing step, the large circuit board 1
00, the internal wiring conductors 3 in the circuit board area 101,
Via hole conductor 4, surface wiring conductor 2, discarded ear area 102
A land electrode 104, a dummy via-hole conductor 103,
There is a difference in temperature at which sintering shrinkage starts between the glass-ceramic layers 1a to 1e, thereby causing warpage deformation.

Specifically, the glass-ceramic layers 1a to 1
Before the sintering reaction in 1e, the sintering reaction of the conductive powder of the conductive material is performed first. Therefore, the glass-ceramic layer 1
When a to 1e are about to undergo a sintering reaction, the conductor of the conductive material has a certain degree of strength due to the progress of the sintering reaction. Therefore, since the dummy via-hole conductor 103 having the land electrode 104 is also formed in the discard ear region 102 around the large-sized circuit board 100, the sintering behavior of the discard ear portion 102 is substantially reduced to the circuit board region. 101, the large circuit board 100
In particular, it is possible to prevent warpage deformation occurring in the peripheral portion which is a free end.

For example, the dummy via-hole conductor 103 penetrating in the thickness direction of the abandoned ear region 102 acts to maintain the current state in the thickness direction with respect to the stress for generating the warp deformation. Reference numeral 104 functions to planarly prevent a stress that tends to generate warpage deformation.

Due to these synergistic effects, the discarded ear region 10
Also in 2, the occurrence of the warp deformation can be minimized, whereby the occurrence of the warp deformation in the circuit board 10 adjacent to the discard ear region 102 can be effectively suppressed.

As described above, according to the present invention, even when the electronic component 5 is mounted on the circuit board 10 adjacent to the discard ear region 102, stable mounting is performed. Also, when such a circuit board 10 is mounted on a printed wiring board, stable mounting can be performed.

[0066]

[Experimental Examples] The present inventors have conducted various studies on the effects of the difference in the spacing between the dummy via-hole conductors 103 formed in the abandoned ear region.

The diameter of the dummy via-hole conductor formed in the abandoned ear region 102 is set to 200 μm for the diameter of the via-hole conductor formed in the normal circuit board region. Was formed. The dummy via-hole conductors 103 were not formed, and the intervals between the dummy via-hole conductors 103 were set to 0.05 mm, 0.1 mm, and 0.2 mm.
The warpage of the large circuit board 100 mm and 0.5 mm was examined. The large circuit board 100 is 100 m
A circuit board area 101 of mx 100 mm and around it,
A discard ear region 102 having a width of 5 mm is formed. From this circuit board area 101, finally, 100 circuit boards 1
0 is extracted. The number of stacked large circuit boards is, for example, six glass-ceramic layers.

As an evaluation, the displacement Δx of the entire surface of the large circuit board 100 was measured. In general, it is important that Δx be within 50 μm in consideration of component mounting reliability and mounting reliability on a printed wiring board.

As a result, the adjacent via-hole conductor 103
When the spacing was 0.05 mm, a crack was generated when a through-hole serving as the via-hole conductor 103 was formed in the green sheet by punching, and even a sample could not be prepared substantially.

When the distance is 0.1 mm, Δx is 30 μm.
m, which is favorable in terms of component mounting reliability and mounting reliability on a printed wiring board.

Further, when the interval is 0.3 mm, Δx is 45
μm, which is favorable in terms of component mounting reliability and mounting reliability on a printed wiring board.

Further, when the interval is 0.5 mm, Δx is 10
0 μm, resulting in poor mounting reliability and mounting reliability.

If the interval is relatively small, the land electrodes of the adjacent dummy via-hole conductors are joined to each other, so that the land electrodes are provided on the large circuit board 100 between the abandoned ear regions as a whole. However, such a structure may be adopted.

[0074]

As described above, according to the present invention, a dummy via-hole conductor having a land electrode is provided in a disposable ear region provided around a large circuit board from which a plurality of circuit boards can be extracted. Because it was formed at intervals of 0.3 mm,
Since the strength of the abandoned ear region in the firing step is substantially the same as that of the circuit board region, warpage deformation that occurs in the entire large circuit board can be effectively suppressed.

As a result, a circuit board which has a small amount of warpage among a plurality of circuit boards extracted from the circuit board area, has excellent component mountability, and has excellent mountability on a printed wiring board can be easily achieved. Becomes

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a circuit board according to the present invention.

FIG. 2 is a partial cross-sectional view of a large circuit board according to the present invention.

FIG. 3 is a partial plan view of a large circuit board according to the present invention.

[Explanation of symbols]

 10 Circuit board 1 Laminated body 1a-1e Glass-ceramic layer 2 Surface wiring conductor 3 Internal wiring conductor 4. Via-hole conductor 100 Large circuit board 101 Circuit board area 102 Discard ear area 103 Dummy via-hole conductor 104 Land electrode

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yoichi Makino 1-1-1, Yamashita-cho, Kokubu-shi, Kagoshima Inside the Kyocera Corporation's Kagoshima Kokubu Plant

Claims (1)

[Claims] 1. A circuit board region from which a plurality of circuit boards can be extracted, and a discarded ear region around the circuit board region, and a conductor film serving as an internal wiring conductor and / or a conductor serving as a via hole conductor are attached. A plurality of glass-ceramic sheets are laminated and fired to obtain a large circuit board, and the large circuit board is divided into each circuit board to form a plurality of circuit boards. In each of the glass-ceramic sheets, a plurality of dummy via-hole conductors having land electrodes are disposed in the discarded ear region.
A method for manufacturing a circuit board, wherein the circuit board is formed at an interval of 1 to 0.3 mm.