JPH04246890A - Manufacture of multilayer ceramic board - Google Patents
Manufacture of multilayer ceramic boardInfo
- Publication number
- JPH04246890A JPH04246890A JP1202691A JP1202691A JPH04246890A JP H04246890 A JPH04246890 A JP H04246890A JP 1202691 A JP1202691 A JP 1202691A JP 1202691 A JP1202691 A JP 1202691A JP H04246890 A JPH04246890 A JP H04246890A
- Authority
- JP
- Japan
- Prior art keywords
- multilayer ceramic
- laminate
- ceramic substrate
- pressing plate
- pressing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 239000000919 ceramic Substances 0.000 title claims abstract description 35
- 238000004519 manufacturing process Methods 0.000 title claims description 15
- 239000000945 filler Substances 0.000 claims abstract description 5
- 238000003825 pressing Methods 0.000 claims description 28
- 239000000758 substrate Substances 0.000 claims description 28
- 238000000034 method Methods 0.000 claims description 8
- 238000010030 laminating Methods 0.000 claims description 4
- 230000000149 penetrating effect Effects 0.000 claims description 2
- 238000009792 diffusion process Methods 0.000 claims 2
- 239000006185 dispersion Substances 0.000 claims 1
- 239000010410 layer Substances 0.000 description 10
- 238000010304 firing Methods 0.000 description 8
- 239000007789 gas Substances 0.000 description 7
- 239000011230 binding agent Substances 0.000 description 4
- 239000004020 conductor Substances 0.000 description 4
- 239000010409 thin film Substances 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 239000011261 inert gas Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910052750 molybdenum Inorganic materials 0.000 description 2
- 239000011733 molybdenum Substances 0.000 description 2
- 238000007747 plating Methods 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 238000004080 punching Methods 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- 238000003892 spreading Methods 0.000 description 2
- 238000004544 sputter deposition Methods 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 238000007872 degassing Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000011229 interlayer Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229920001721 polyimide Polymers 0.000 description 1
- 239000009719 polyimide resin Substances 0.000 description 1
- 238000013022 venting Methods 0.000 description 1
Landscapes
- Production Of Multi-Layered Print Wiring Board (AREA)
Abstract
Description
【０００１】0001
【産業上の利用分野】本発明は、大型電子機器の回路構
成に広く使用される多層セラミック基板の製造方法に関
する。最近、特に、大型電算機等のプリント板ユニット
に実装される半導体チップが高集積化されるに伴い、そ
の半導体チップを実装する多層セラミック基板も微細化
された導体パターンと微細な層間接続用のビアを高密度
に形成することが必要となり、そのためビアホールに導
体粉末の充填と配線パターンの印刷を行ったグリーンシ
ートを複数枚積層したグリーンシート積層体（以下積層
体と略称する）を焼成することでセラミック絶縁基体を
形成している。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a multilayer ceramic substrate widely used in circuit configurations of large electronic devices. Recently, as semiconductor chips mounted on printed circuit board units such as large computers have become more highly integrated, the multilayer ceramic substrates on which the semiconductor chips are mounted are also becoming more sophisticated with finer conductor patterns and finer interlayer connections. It is necessary to form vias with high density, and for this purpose, a green sheet laminate (hereinafter referred to as laminate), which is a stack of multiple green sheets whose via holes are filled with conductor powder and printed with wiring patterns, is fired. This forms a ceramic insulating substrate.
【０００２】しかるに、このセラミック絶縁基体には反
りと内層に空洞等が生じて、表面に形成する薄膜との間
に接続障害と電子部品実装時において空洞が破壊する等
の問題が発生するので、セラミック絶縁基板の反りおよ
び内層の空洞を最小限とすることができる新しい多層セ
ラミック基板の製造方法が必要とされている。However, warpage and cavities occur in the inner layer of this ceramic insulating substrate, causing problems such as connection failure with the thin film formed on the surface and destruction of the cavities when electronic components are mounted. There is a need for a new method of manufacturing multilayer ceramic substrates that can minimize warpage and inner layer voids in ceramic insulating substrates.
【０００３】0003
【従来の技術】従来広く使用されている多層セラミック
基板の製造方法は、図５に示すようにパンチングシステ
ム等により多数個の微細なビアホールを穿孔して、その
ビアホールに導電性の優れた金属粉末，例えば銅よりな
るビア充填剤を充填し、その片面または両面に内層パタ
ーンを印刷したグリーンシートを複数枚積層して押圧す
ることにより積層体１を形成する。この積層体１をセッ
ター４等の焼成治具に載置して、その上部より耐熱性を
有する例えばモリブデン等の厚板から形成した押圧板３
により矢印方向へ均一に押圧して、側壁と上下にヒータ
を配設した焼成炉の不活性ガス雰囲気中で高温焼成する
ことによりセラミック絶縁基体２が形成される。[Prior Art] As shown in FIG. 5, a method of manufacturing a multilayer ceramic substrate that has been widely used in the past involves punching a large number of fine via holes using a punching system or the like, and filling the via holes with metal powder having excellent conductivity. The laminate 1 is formed by laminating and pressing a plurality of green sheets filled with a via filler made of, for example, copper and having an inner layer pattern printed on one or both sides thereof. This laminate 1 is placed on a baking jig such as a setter 4, and from the top thereof a press plate 3 formed from a thick plate having heat resistance, such as molybdenum, etc.
The ceramic insulating base 2 is formed by pressing uniformly in the direction of the arrow and firing at a high temperature in an inert gas atmosphere in a firing furnace equipped with heaters on the side walls and above and below.
【０００４】そして、このセラミック絶縁基体の表裏両
面を研削して両面が平行な平板状に成形して、表面にス
パッタ，またはメッキ等により導体薄膜を形成すること
により多層セラミック基板が製造されている。[0004] Then, a multilayer ceramic substrate is manufactured by grinding the front and back surfaces of this ceramic insulating substrate, forming it into a flat plate with both surfaces parallel, and forming a conductive thin film on the surface by sputtering or plating. .
【０００５】[0005]
【発明が解決しようとする課題】以上説明した従来の多
層セラミック基板の製造方法で問題となるのは、グリー
ンシートの積層体１を平板状の押圧板３により押圧して
不活性ガス雰囲気中で高温焼成すると、積層体１の各位
置に対して熱伝播の差が生じて焼成されたセラミック絶
縁基体に大きな反りが発生して、このセラミック絶縁基
体の両面を平面状に研削するとセラミック界面が２〜４
層にわたって露出し、表面に導体薄膜を形成する時にポ
リイミド樹脂のは密着不良および導体間の短絡等の欠陥
が発生するという問題が生じている。[Problems to be Solved by the Invention] The problem with the conventional method of manufacturing a multilayer ceramic substrate described above is that the green sheet laminate 1 is pressed by a flat pressing plate 3 in an inert gas atmosphere. When fired at a high temperature, differences in heat propagation occur at each location of the laminate 1, causing large warpage in the fired ceramic insulating base, and when both sides of the ceramic insulating base are ground into a flat shape, the ceramic interface is ~4
When polyimide resin is exposed across layers and a conductor thin film is formed on the surface, problems such as poor adhesion and short circuits between conductors occur.
【０００６】また、積層体１の上部より押圧板３で均一
に押圧して高温焼成しているために、各グリーンシート
に含まれているバインダーより発生するガスの逃げる方
向は積層体１の四側面からのみとなるので、図６に示す
ようにセラミック絶縁基体２のそれぞれセラミック界面
に空洞２ａが生じ、電子部品実装時における加熱により
その空洞２ａが膨張してクラック２ｂ発生し、その部分
が欠け落ちるという問題も生じている。Furthermore, since the laminate 1 is pressed uniformly from the top by the pressing plate 3 and fired at a high temperature, the direction in which the gas generated from the binder contained in each green sheet escapes is from the four sides of the laminate 1. As shown in FIG. 6, cavities 2a are formed at each ceramic interface of the ceramic insulating base 2, and the cavities 2a expand due to heating during electronic component mounting, causing cracks 2b to occur, resulting in cracks in that part. There is also the problem of falling.
【０００７】本発明は上記のような問題点に鑑み、焼成
時の反りおよび内層の空洞を最小限とすることができる
新しい多層セラミック基板の製造方法の提供を目的とす
る。SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention aims to provide a new method for manufacturing a multilayer ceramic substrate that can minimize warping during firing and cavities in the inner layer.
【０００８】[0008]
【課題を解決するための手段】本発明は、図１に示すよ
うにビア孔に導電性の優れたビア充填剤を充填して内層
パターンを印刷した複数枚のグリーンシートを積層・押
圧して積層体１を形成し、図２に示すように前記グリー
ンシートより発生するガスの散開手段１３−１を形成し
た耐熱性の高い押圧板１３により当該積層体１を押圧し
て焼成することによりセラミック絶縁基体を形成する。[Means for Solving the Problems] As shown in FIG. 1, the present invention consists of laminating and pressing a plurality of green sheets each having a via hole filled with a highly conductive via filler and an inner layer pattern printed thereon. A ceramic material is formed by forming a laminate 1 and pressing and firing the laminate 1 with a highly heat-resistant press plate 13 having a means 13-1 for dispersing gas generated from the green sheet, as shown in FIG. Form an insulating substrate.
【０００９】[0009]
【作用】本発明では、ガスの散開手段１３−１を形成し
た押圧板１３により積層体１を押圧しているから、焼成
時にグリーンシートから発生するバインダーガスは散開
手段１３−１を通って外部に散開するため、形成された
セラミック絶縁基体の反りおよび内層の空洞を最小限と
することが可能となる。[Operation] In the present invention, since the laminate 1 is pressed by the pressing plate 13 forming the gas spreading means 13-1, the binder gas generated from the green sheet during firing passes through the spreading means 13-1 to the outside. Therefore, it is possible to minimize warping of the formed ceramic insulating substrate and cavities in the inner layer.
【００１０】0010
【実施例】以下図１ないし図４について本発明の実施例
を説明する。図１は本発明の一実施例による多層セラミ
ック基板の製造方法を示す模式図、図２は第一実施例の
押圧板を示す斜視図、図３は第二実施例の押圧板を示す
斜視図、図４は第三実施例の押圧板の部分拡大斜視図を
示し、図中において、図５と同一部材には同一記号が付
してあるが、その他の１３， ２３， ３３はグリーン
シート積層体を焼成する時に押圧する第一， 第二，
第三の押圧板である。DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. FIG. 1 is a schematic diagram showing a method for manufacturing a multilayer ceramic substrate according to an embodiment of the present invention, FIG. 2 is a perspective view showing a pressure plate of the first embodiment, and FIG. 3 is a perspective view showing a pressure plate of the second embodiment. , FIG. 4 shows a partially enlarged perspective view of the pressing plate of the third embodiment. In the figure, the same members as those in FIG. The first, second,
This is the third pressing plate.
【００１１】第一の押圧板１３は、図１に示すように積
層体１と等しい外形寸法に成形した耐熱性および耐熱強
度の高い材料，例えばモリブデン，アルミナ等よりなる
平板の片面側に、図２に示すようにバインダーガスを逃
がす微小幅の角，或いはＵ字状の溝１３−１を一定ピッ
チで格子状に刻設したものである。第二の押圧板２３は
、図３に示すように積層体１と等しい外形寸法に成形し
た耐熱強度の高い平板に、表裏を貫通する小径のガス抜
き用孔２３−１を多数個穿設したものである。As shown in FIG. 1, the first pressing plate 13 is made of a material with high heat resistance and heat resistance strength, such as molybdenum, alumina, etc., and is formed to have the same external dimensions as the laminate 1. As shown in FIG. 2, narrow corners or U-shaped grooves 13-1 for letting the binder gas escape are carved in a lattice pattern at a constant pitch. As shown in FIG. 3, the second pressing plate 23 is a flat plate with high heat resistance and strength formed to have the same external dimensions as the laminate 1, and a large number of small-diameter degassing holes 23-1 are bored through the front and back sides. It is something.
【００１２】第三の押圧板３３は、図４に示す如く上記
の第一押圧板１３と同様に平板の一方の面に微小幅の溝
３３−１を格子状に刻設して、各溝３３−１の底面から
他方の面に貫通するガス抜き用孔３３−２を例えば各溝
３３−１のそれぞれ交点に穿設したものである。上記部
材を使用した多層セラミック基板の製造方法は、図１に
示すように多数個の微細なビアホールに導電性の優れた
金属，例えば銅粉末よりなるビア充填剤を充填して、そ
の片面， または両面に内層パターンを印刷したグリー
ンシートを複数枚積層して押圧することにより積層体１
が形成される。As shown in FIG. 4, the third pressing plate 33 has minute width grooves 33-1 carved in a lattice pattern on one surface of the flat plate in the same way as the first pressing plate 13 described above. Gas venting holes 33-2 penetrating from the bottom surface of the groove 33-1 to the other surface are formed, for example, at the intersections of the respective grooves 33-1. As shown in Figure 1, the method for manufacturing a multilayer ceramic board using the above-mentioned members is to fill a large number of fine via holes with a via filler made of a highly conductive metal, such as copper powder, and to Laminate 1 is made by laminating and pressing multiple green sheets with inner layer patterns printed on both sides.
is formed.
【００１３】この積層体１をセッター４等の焼成治具に
載置して、例えばその上面に前記押圧板１３の溝１３−
１形成面を当接させることにより、積層体１の上面より
矢印方向へ均一に押圧した状態で高温で焼成してセラミ
ック絶縁基体を形成する。このセラミック絶縁基体の表
裏両面を従来と同様に研削して両面が平行な平板状に成
形して、スパッタ，またはメッキ等により導体薄膜導体
薄膜を形成することにより多層セラミック基板を製造し
ている。This laminate 1 is placed on a baking jig such as a setter 4, and the groove 13- of the pressing plate 13 is formed on the top surface of the laminate 1, for example.
By bringing the forming surfaces of the laminate 1 into contact with each other, the laminate 1 is fired at a high temperature while being pressed uniformly in the direction of the arrow from the upper surface of the laminate 1 to form a ceramic insulating substrate. A multilayer ceramic substrate is manufactured by grinding both the front and back surfaces of this ceramic insulating substrate in the same manner as in the past, forming a flat plate with both surfaces parallel, and forming a conductive thin film by sputtering, plating, or the like.
【００１４】その結果、焼成時に発生するグリーンシー
トのバインダーガスが押圧板１３の溝１３−１を通って
容易に発散させることが可能となるので、焼成されたセ
ラミック絶縁基体の反りおよび内層に生じる空洞を最小
限にすることができる。以上、図示実施例に基づき説明
したが、本発明は上記実施例の態様のみに限定されるも
のでなく、例えば積層体の上下に押圧板を配して焼成し
ても良く、上部のみに限定しなくても良い。As a result, the binder gas of the green sheet generated during firing can be easily diffused through the grooves 13-1 of the pressing plate 13, thereby preventing warping of the fired ceramic insulating substrate and the inner layer. Cavities can be minimized. The above description has been made based on the illustrated embodiments, but the present invention is not limited to the embodiments described above. For example, pressing plates may be placed above and below the laminate for firing, and the present invention may be limited only to the upper part. You don't have to.
【００１５】[0015]
【発明の効果】以上の説明から明らかなように本発明に
よれば極めて簡単な方法で、焼成時に発生するセラミッ
ク絶縁基体の反りおよび内層の空洞を最小限にすること
ができる等の利点があり、著しい経済的及び、信頼性向
上の効果が期待できる多層セラミック基板の製造方法を
提供することができる。[Effects of the Invention] As is clear from the above explanation, the present invention has advantages such as being able to minimize warping of the ceramic insulating substrate and cavities in the inner layer that occur during firing with an extremely simple method. Therefore, it is possible to provide a method for manufacturing a multilayer ceramic substrate that can be expected to be significantly economical and to improve reliability.
【図１】 本発明の一実施例による多層セラミック基
板の製造方法を示す模式図である。FIG. 1 is a schematic diagram showing a method for manufacturing a multilayer ceramic substrate according to an embodiment of the present invention.
【図２】 第一実施例の押圧板を示す斜視図である。FIG. 2 is a perspective view showing the pressing plate of the first embodiment.
【図３】 第二実施例の押圧板を示す斜視図である。FIG. 3 is a perspective view showing a pressing plate of a second embodiment.
【図４】 第三実施例の押圧板を示す部分拡大斜視図
である。FIG. 4 is a partially enlarged perspective view showing a press plate of a third embodiment.
【図５】 従来の多層セラミック基板の製造方法を示
す模式図である。FIG. 5 is a schematic diagram showing a conventional method for manufacturing a multilayer ceramic substrate.
【図６】 従来の問題点を示す断面図である。FIG. 6 is a cross-sectional view showing problems with the conventional technology.
１は積層体、
４はセッター、１３， ２３， ３３は押圧
板、 １３−１， ３
３−１は溝、
２３−１， ３３−２は孔、1 is a laminate;
4 is a setter, 13, 23, 33 are pressing plates, 13-1, 3
3-1 is a groove, 23-1, 33-2 are holes,
Claims (4)
充填して内層パターンを印刷した複数枚のグリーンシー
トを積層・押圧した積層体（１） を、該積層体（１）
から発生するガスの散開手段（１３−１）を設けた押
圧板（１３）により押圧して焼成したことを特徴とする
多層セラミック基板の製造方法。Claim 1: A laminate (1) obtained by laminating and pressing a plurality of green sheets each having a filler with excellent conductivity filled in the via hole and printed with an inner layer pattern.
A method for manufacturing a multilayer ceramic substrate, characterized in that the multilayer ceramic substrate is pressed and fired by a pressing plate (13) provided with a means (13-1) for dispersing gas generated from the substrate.
圧面に微小幅の溝（１３−１）を一定ピッチで格子状に
刻設したことを特徴とする請求項１記載の多層セラミッ
ク基板の製造方法。2. The multilayer ceramic substrate according to claim 1, wherein the gas diffusion means of the pressing plate has grooves (13-1) of minute width carved in a lattice shape at a constant pitch on the pressing surface. Production method.
圧面の表裏を貫通する小径の孔（２３−１）を複数個穿
設したことを特徴とする請求項１記載の多層セラミック
基板の製造方法。3. The production of a multilayer ceramic substrate according to claim 1, wherein the gas diffusion means of the pressing plate has a plurality of small diameter holes (23-1) bored through the front and back sides of the pressing surface. Method.
圧面の表面に微小幅の溝（３３−１）を刻設するととも
に、当該溝（３３−１）と裏面とを貫通する複数個の孔
（３３−２）を穿設したことを特徴とする請求項１記載
の多層セラミック基板の製造方法。4. The gas dispersion means of the pressing plate has a groove (33-1) of minute width carved on the surface of the pressing surface, and a plurality of grooves (33-1) penetrating the groove (33-1) and the back surface. 2. The method of manufacturing a multilayer ceramic substrate according to claim 1, further comprising forming holes (33-2).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1202691A JPH04246890A (en) | 1991-02-01 | 1991-02-01 | Manufacture of multilayer ceramic board |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1202691A JPH04246890A (en) | 1991-02-01 | 1991-02-01 | Manufacture of multilayer ceramic board |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04246890A true JPH04246890A (en) | 1992-09-02 |
Family
ID=11794098
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1202691A Withdrawn JPH04246890A (en) | 1991-02-01 | 1991-02-01 | Manufacture of multilayer ceramic board |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04246890A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5565557A (en) * | 1993-12-24 | 1996-10-15 | Mitsubishi Chemical Corporation | Process for producing sucrose fatty acid ester |
| JP2002314251A (en) * | 2001-04-09 | 2002-10-25 | Matsushita Electric Ind Co Ltd | Method for manufacturing ceramic multilayer board |
-
1991
- 1991-02-01 JP JP1202691A patent/JPH04246890A/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5565557A (en) * | 1993-12-24 | 1996-10-15 | Mitsubishi Chemical Corporation | Process for producing sucrose fatty acid ester |
| JP2002314251A (en) * | 2001-04-09 | 2002-10-25 | Matsushita Electric Ind Co Ltd | Method for manufacturing ceramic multilayer board |
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