JP2003124054A - Method of manufacturing laminated ceramic electronic part - Google Patents
Method of manufacturing laminated ceramic electronic partInfo
- Publication number
- JP2003124054A JP2003124054A JP2001317791A JP2001317791A JP2003124054A JP 2003124054 A JP2003124054 A JP 2003124054A JP 2001317791 A JP2001317791 A JP 2001317791A JP 2001317791 A JP2001317791 A JP 2001317791A JP 2003124054 A JP2003124054 A JP 2003124054A
- Authority
- JP
- Japan
- Prior art keywords
- temperature
- ceramic electronic
- laminated
- electronic component
- firing
- 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.)
- Pending
Links
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は例えば積層セラミッ
クコンデンサに代表される積層セラミック電子部品の製
造方法に関するもので、特にＮｉ等の卑金属を電極に用
いた積層セラミックグリーンチップの脱バイ焼成方法に
関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a laminated ceramic electronic component represented by, for example, a laminated ceramic capacitor, and more particularly to a debye firing method for a laminated ceramic green chip using a base metal such as Ni as an electrode. Is.
【０００２】[0002]
【従来の技術】以下に一般的な積層セラミック電子部品
として積層セラミックコンデンサの構成を説明する。2. Description of the Related Art The structure of a laminated ceramic capacitor as a general laminated ceramic electronic component will be described below.
【０００３】図３は脱バイ焼成における温度図、図４は
積層セラミックコンデンサの一部切欠斜視図である。FIG. 3 is a temperature diagram in de-baking firing, and FIG. 4 is a partially cutaway perspective view of a monolithic ceramic capacitor.
【０００４】図４において１０１は積層セラミックコン
デンサであり、この積層セラミックコンデンサ１０１は
誘電体で形成したグリーンシート１０２と内部電極１０
３，１０４とを交互に積層して圧着し積層セラミックグ
リーンチップ１０５を形成し、前記積層セラミックグリ
ーンチップ１０５を高温下で焼成した後に前記内部電極
１０３，１０４とそれぞれ接続した外部電極１０６，１
０７を形成してこの外部電極１０６,１０７の間にコン
デンサを構成している。In FIG. 4, reference numeral 101 denotes a monolithic ceramic capacitor. The monolithic ceramic capacitor 101 includes a green sheet 102 made of a dielectric material and an internal electrode 10.
3 and 104 are alternately laminated and pressure-bonded to form a laminated ceramic green chip 105, and the laminated ceramic green chip 105 is fired at a high temperature, and then external electrodes 106 and 1 connected to the internal electrodes 103 and 104, respectively.
07 is formed to form a capacitor between the external electrodes 106 and 107.
【０００５】以上のように構成された積層セラミックコ
ンデンサ１０１について、以下にその製造方法を説明す
る。A method of manufacturing the monolithic ceramic capacitor 101 having the above-described structure will be described below.
【０００６】まず、セラミックス原料と有機結合材成分
とを混合して形成した前記グリーンシート１０２と内部
電極１０３，１０４とを積層して圧着し積層セラミック
グリーンチップ１０５を形成する。First, the green sheet 102 formed by mixing a ceramic raw material and an organic binder component and the internal electrodes 103, 104 are laminated and pressure-bonded to form a laminated ceramic green chip 105.
【０００７】次いで、前記積層セラミックグリーンチッ
プ１０５を脱脂炉内に入れてこの積層セラミックグリー
ンチップ１０５の成形のために加えられた可塑剤及び有
機バインダーを熱分解して除去するために脱バイ焼成を
行う。Next, the laminated ceramic green chip 105 is placed in a degreasing furnace and de-baked to remove the plasticizer and organic binder added for molding the laminated ceramic green chip 105 by thermal decomposition. To do.
【０００８】前記脱バイ焼成は図３の温度図に示す通
り、前記脱脂炉内の温度を常温から６００℃まで１時間
に１００℃〜２００℃の割合で昇温し６００℃で５時間
維持する。As shown in the temperature diagram of FIG. 3, the de-baking firing raises the temperature in the degreasing furnace from room temperature to 600 ° C. at a rate of 100 ° C. to 200 ° C. for 1 hour and maintains the temperature at 600 ° C. for 5 hours. .
【０００９】その後、前記恒温炉内から本焼成炉内に前
記積層セラミックグリーンチップ１０５を搬送し、前記
本焼成炉内を１３００℃まで除々に昇温して焼成を行い
焼結体とし、この焼結体の端面に前記内部電極１０３，
１０４と接続するように外部電極１０６，１０７を塗布
して焼き付け積層セラミックコンデンサ１０１を完成す
る。Thereafter, the monolithic ceramic green chip 105 is conveyed from the constant temperature oven into the main firing furnace, and the inside of the main firing furnace is gradually heated to 1300 ° C. to be fired to obtain a sintered body. The internal electrodes 103,
External electrodes 106 and 107 are applied so as to be connected to 104, and a baked monolithic ceramic capacitor 101 is completed.
【００１０】[0010]
【発明が解決しようとする課題】しかしながら、近年の
積層セラミック電子部品は、高性能化と低コスト化とい
う相反する市場要望に応えるため、積層セラミック電子
部品を構成するグリーンシートの薄層化及び多積層化と
が急激な勢いで進んでおり、前記従来の積層セラミック
コンデンサ１０１の脱バイ焼成方法は、内部電極１０
３，１０４として卑金属のＮｉあるいはＮｉを主成分と
する金属を用いる場合、前記Ｎｉの酸化を防止するため
低い酸素分圧下での脱バイ焼成が余儀なくされるので脱
バイが不十分となり易く、前記積層セラミックグリーン
チップ１０５を焼成した焼結体の内部にバインダー成分
が残留カーボンとして残り、これが製品特性を劣化させ
る要因となり、高い信頼性を確保することが困難である
という問題点があった。However, in recent years, in order to meet the conflicting market demands for higher performance and lower cost, the multilayer ceramic electronic components of recent years are made thin and have a large number of green sheets constituting the multilayer ceramic electronic components. The multilayering is rapidly progressing, and the conventional debye firing method for the monolithic ceramic capacitor 101 is the internal electrode 10
When a base metal Ni or a metal containing Ni as a main component is used as 3,104, de-baking is unavoidably performed under a low oxygen partial pressure in order to prevent the oxidation of Ni, and de-bye tends to be insufficient. A binder component remains as residual carbon inside the sintered body obtained by firing the multilayer ceramic green chip 105, which causes deterioration of product characteristics, and there is a problem that it is difficult to secure high reliability.
【００１１】また、近年の薄層多積層化品においては、
積層体内部にひずみが生じ易く、有機バインダーの急激
な分解により、ヒビやクラックといった構造欠陥が発生
しやすいという問題点があった。Further, in recent thin layer multi-layered products,
There has been a problem that strain is likely to occur inside the laminate and structural defects such as cracks and cracks are likely to occur due to rapid decomposition of the organic binder.
【００１２】本発明は前記従来の問題点を解決するもの
で、ヒビやクラックといった構造欠陥の発生を抑制し、
信頼性が高く安定した特性を得る積層セラミック電子部
品の製造方法を提供することを目的とするものである。The present invention solves the above-mentioned conventional problems by suppressing the occurrence of structural defects such as cracks and cracks,
An object of the present invention is to provide a method for manufacturing a monolithic ceramic electronic component that is highly reliable and has stable characteristics.
【００１３】[0013]
【課題を解決するための手段】前記の課題を解決するた
めに本発明は以下の構成を有するものである。In order to solve the above problems, the present invention has the following constitution.
【００１４】本発明の請求項１に記載の発明は、セラミ
ックス原料と有機結合材成分とを混合して形成したグリ
ーンシートとＮｉを主成分とする内部電極とを積層した
積層セラミックグリーンチップを常温〜略１３００℃の
焼成温度まで昇温し脱バイ焼成する際に、前記焼成温度
の２０℃〜４００℃の昇温範囲ではその昇温速度を２５
℃／Ｈｒ以下とする積層セラミック電子部品の製造方法
であり、これにより、グリーンシートとＮｉを主成分と
する内部電極中に含まれる可塑剤を急激な分解を避けて
徐々に十分分解除去し、その後の有機バインダーの分解
除去を円滑にするという作用効果が得られる。The invention according to claim 1 of the present invention is a laminated ceramic green chip in which a green sheet formed by mixing a ceramic raw material and an organic binder component and an internal electrode containing Ni as a main component are laminated at room temperature. ~ When de-baking is performed by raising the temperature to a firing temperature of approximately 1300 ° C, the temperature raising rate is 25 in the temperature raising range of 20 ° C to 400 ° C.
C./Hr or less, which is a method for manufacturing a multilayer ceramic electronic component, whereby a plasticizer contained in the green sheet and the internal electrode containing Ni as a main component is gradually and sufficiently decomposed and removed while avoiding rapid decomposition, The effect of facilitating the subsequent decomposition and removal of the organic binder can be obtained.
【００１５】本発明の請求項２に記載の発明は、セラミ
ックス原料と有機結合材成分とを混合して形成したグリ
ーンシートとＮｉを主成分とする内部電極とを積層した
積層セラミックグリーンチップを常温〜略１３００℃の
焼成温度まで昇温し脱バイ焼成する際に、前記焼成温度
の４００℃〜６００℃の昇温範囲ではその昇温速度を２
０℃／Ｈｒ以下とする積層セラミック電子部品の製造方
法であり、これにより、有機バインダーの急激な分解を
避けて徐々に十分分解除去でき、最終の焼結体内部にカ
ーボンが残留することを防止することができるという作
用効果が得られる。The invention according to claim 2 of the present invention is a laminated ceramic green chip in which a green sheet formed by mixing a ceramic raw material and an organic binder component and an internal electrode containing Ni as a main component are laminated at room temperature. ~ When de-baking is performed by raising the temperature to a firing temperature of approximately 1300 ° C, the heating rate is 2 in the temperature raising range of 400 ° C to 600 ° C.
This is a method for producing a monolithic ceramic electronic component at 0 ° C./hr or less, which allows the organic binder to be gradually decomposed and removed while avoiding a rapid decomposition, and prevents carbon from remaining inside the final sintered body. The effect of being able to do is obtained.
【００１６】本発明の請求項３に記載の発明は、焼成温
度の４００℃〜４５０℃の昇温範囲では、その昇温速度
を１０℃／Ｈｒ以下とする請求項１または２に記載の積
層セラミック電子部品の製造方法であり、これにより、
有機バインダーの分解が最も盛んな温度範囲における急
激な分解を避けつつ徐々に十分分解除去し、最終の焼結
体内部にカーボンが残留することを防止することができ
るという作用効果が得られる。The invention according to claim 3 of the present invention is the lamination according to claim 1 or 2, wherein the heating rate is 10 ° C./Hr or less in the heating temperature range of 400 ° C. to 450 ° C. It is a method for manufacturing a ceramic electronic component.
It is possible to obtain an effect that the organic binder can be gradually decomposed and removed while avoiding the rapid decomposition in the temperature range where decomposition is most active, and carbon can be prevented from remaining inside the final sintered body.
【００１７】本発明の請求項４に記載の発明は、焼成温
度の４００℃〜６００℃の昇温範囲では、その昇温速度
を２０℃／Ｈｒ以下とする請求項１または２に記載の積
層セラミック電子部品の製造方法であり、これにより、
グリーンシートとＮｉを主成分とする内部電極中に含ま
れる可塑剤を、急激な分解を避けつつ徐々に十分分解除
去し、その後の有機バインダーの分解除去を円滑化する
という作用効果と、有機バインダーを急激な分解を避け
つつ徐々に十分分解除去し、最終の焼結体内部にカーボ
ンが残留することを防止することができるという作用効
果とが得られる。The invention according to claim 4 of the present invention is the lamination according to claim 1 or 2, wherein the heating rate is 20 ° C./Hr or less in the heating temperature range of 400 ° C. to 600 ° C. It is a method for manufacturing a ceramic electronic component.
The plasticizer contained in the green sheet and the internal electrode containing Ni as a main component is gradually and sufficiently decomposed and removed while avoiding rapid decomposition, and the subsequent organic binder is smoothly decomposed and removed. Is gradually and sufficiently decomposed and removed while avoiding abrupt decomposition, and carbon can be prevented from remaining inside the final sintered body.
【００１８】本発明の請求項５に記載の発明は、焼成温
度の４００℃〜６００℃の昇温範囲では、その昇温速度
を２０℃／Ｈｒ以下とし、この昇温範囲の４００℃〜４
５０℃の範囲では、その昇温速度を１０℃／Ｈｒ以下と
する請求項１または２に記載の積層セラミック電子部品
の製造方法であり、これにより、グリーンシートとＮｉ
を主成分とする内部電極中に含まれる可塑剤を、急激な
分解を避けつつ徐々に十分分解除去し、その後の有機バ
インダーの分解除去を円滑化するという作用効果と、有
機バインダーを急激な分解を避けつつ徐々に十分分解除
去し、最終の焼結体内部にカーボンが残留することを防
止することができるという作用効果とが得られる。According to the fifth aspect of the present invention, in the heating temperature range of 400 ° C. to 600 ° C., the heating rate is 20 ° C./Hr or less, and the heating range is 400 ° C. to 4 ° C.
The method for producing a monolithic ceramic electronic component according to claim 1 or 2, wherein the temperature rising rate is 10 ° C / Hr or less in the range of 50 ° C.
The plasticizer contained in the internal electrode that contains as a main component is gradually decomposed and removed while avoiding rapid decomposition, and the subsequent effect of facilitating the decomposition and removal of the organic binder and the rapid decomposition of the organic binder. It is possible to obtain a working effect that carbon can be prevented from remaining in the final sintered body by gradually decomposing and removing it while avoiding the above.
【００１９】本発明の請求項６に記載の発明は、窒素ガ
ス、水素ガス、炭酸ガス、水蒸気の中から選ばれたガス
雰囲気及びこれらの中から２つ以上選ばれたガス雰囲気
中で脱バイ焼成を行う請求項１または２に記載の積層セ
ラミック電子部品の製造方法であり、これらのガスを所
定割合で混合することにより、酸素分圧を容易に精度良
く制御することができるという作用効果が得られる。The invention according to claim 6 of the present invention is a degassing process in a gas atmosphere selected from nitrogen gas, hydrogen gas, carbon dioxide gas and water vapor, and in a gas atmosphere selected from two or more of these. The method for producing a monolithic ceramic electronic component according to claim 1 or 2, wherein firing is performed, and by mixing these gases at a predetermined ratio, the oxygen partial pressure can be easily and accurately controlled. can get.
【００２０】本発明の請求項７に記載の発明は、有機結
合成分が重量平均分子量４０万以上のポリオレフィンで
ある請求項１または２に記載の積層セラミック電子部品
の製造方法であり、これにより、分解しやすい有機バイ
ンダーを用いて、その分解が盛んな温度範囲の昇温をゆ
っくり行うことで有機バインダーの除去を容易にし、さ
らに急激な分解を避けつつ徐々に十分分解除去し、最終
の焼結体内部にカーボンが残留することを防止すること
ができるという作用効果が得られる。The invention according to claim 7 of the present invention is the method for producing a monolithic ceramic electronic component according to claim 1 or 2, wherein the organic binding component is a polyolefin having a weight average molecular weight of 400,000 or more. Using an organic binder that is easy to decompose, the organic binder is easily removed by slowly raising the temperature in a temperature range where decomposition is active. It is possible to obtain the effect of preventing carbon from remaining inside the body.
【００２１】本発明の請求項８に記載の発明は、ポリオ
レフィンがポリエチレン、ポリビニルアルコール及びそ
れらの共重合体からなる群より選ばれた少なくとも一種
のポリオレフィンである請求項７に記載の積層セラミッ
ク電子部品の製造方法であり、これにより、分解しやす
い有機バインダーを用いてその分解が盛んな温度範囲の
昇温をゆっくり行い、有機バインダーの除去を容易に
し、さらに急激な分解を避けつつ徐々に十分分解除去
し、最終の焼結体内部にカーボンが残留することを防止
することができるという作用効果が得られる。The invention according to claim 8 of the present invention is the laminated ceramic electronic component according to claim 7, in which the polyolefin is at least one polyolefin selected from the group consisting of polyethylene, polyvinyl alcohol and copolymers thereof. This is a method of manufacturing, in which the organic binder that is easily decomposed is used to slowly raise the temperature in a temperature range where decomposition is active, facilitates removal of the organic binder, and gradually decomposes sufficiently while avoiding rapid decomposition. It is possible to obtain the effect of removing carbon and preventing carbon from remaining inside the final sintered body.
【００２２】[0022]
【発明の実施の形態】（実施の形態１）以下、実施の形
態１を用いて本発明の特に請求項１及び請求項４，５，
６，７，８に記載の発明について、積層セラミック電子
部品の代表として前記従来例に示した積層セラミックコ
ンデンサ１０１を例にとり説明する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment 1) Hereinafter, Embodiment 1 will be used to particularly describe Claim 1 and Claims 4, 5, and 5 of the present invention.
The inventions 6, 7, and 8 will be described by taking the monolithic ceramic capacitor 101 shown in the conventional example as a representative of monolithic ceramic electronic components.
【００２３】図１は本発明の実施の形態１における脱バ
イ焼成の温度図である。FIG. 1 is a temperature diagram of debye firing in the first embodiment of the present invention.
【００２４】まず、チタン酸バリウムを主成分とする誘
電体材料粉末と重量平均分子量が４００，０００以上の
超高分子ポリエチレン（融点：約１４０℃）とを用いて
誘電体層となるグリーンシート１０２を作製する。この
グリーンシート１０２は一般に多孔率が高く５０％以上
の多孔率を有するものである。First, a dielectric material powder containing barium titanate as a main component and ultra-high molecular weight polyethylene having a weight average molecular weight of 400,000 or more (melting point: about 140 ° C.) are used as a dielectric sheet green sheet 102. To make. The green sheet 102 generally has a high porosity and a porosity of 50% or more.
【００２５】次に、一方、ニッケル電極ペーストをニッ
ケル粉末と溶剤、樹脂、可塑剤等のビヒクルを混合して
作製し、前記グリーンシート１０２にスクリーン印刷法
を用いて塗布して内部電極１０３又は１０４を形成し
た。On the other hand, a nickel electrode paste is prepared by mixing nickel powder with a vehicle such as a solvent, a resin and a plasticizer, and is applied to the green sheet 102 by a screen printing method to form the internal electrode 103 or 104. Was formed.
【００２６】次いで、前記内部電極１０３を形成したグ
リーンシート１０２と前記内部電極１０４を形成したグ
リーンシート１０２とを交互に所定寸法ずらして８０枚
積層した後、その上段と下段に電極ペーストを塗布して
いないグリーンシート１０２を積層して積層体グリーン
ブロック（図示せず）を作製した。Next, the green sheets 102 having the internal electrodes 103 and the green sheets 102 having the internal electrodes 104 are alternately staggered by a predetermined dimension to form 80 sheets, and then an electrode paste is applied to the upper and lower layers. A green sheet (not shown) was manufactured by stacking green sheets 102 that were not stacked.
【００２７】次いで、前記積層体グリーンブロックをこ
の積層体グリーンブロック中に含有するポリエチレンの
融点の−３０℃以上に加熱しながら、１５Ｍｐａにて加
圧して圧着した。Next, the laminate green block was pressure-bonded under pressure of 15 MPa while being heated to -30 ° C. or higher, which is the melting point of polyethylene contained in the laminate green block.
【００２８】次いで、積層体グリーンブロックを３．２
ｍｍ×１．６ｍｍ×１．６ｍｍの寸法に切断して、積層
セラミックグリーンチップ１０５を作製した。このとき
積層セラミックグリーンチップ１０５の両端面は前記内
部電極１０３，１０４の一方の端部がグリーンシート１
０２を挟んで一層おき交互に相対向する異なる端面に露
出した構造とした。Next, the laminated green block is set to 3.2.
A multilayer ceramic green chip 105 was produced by cutting into a size of mm × 1.6 mm × 1.6 mm. At this time, one end of each of the internal electrodes 103, 104 on both end faces of the laminated ceramic green chip 105 is the green sheet 1.
Layers with No. 02 sandwiched between them were exposed on different end faces that are alternately facing each other.
【００２９】次いで、前記積層セラミックグリーンチッ
プ１０５をバッチ式雰囲気炉を用いて、窒素ガスを毎分
１００リットル流しながら、図１の温度図に示すように
脱バイ焼成を行った。尚、本発明の効果を確認するため
に（表１）に示すように昇温速度を変えて最高温度６０
０℃、保持時間５時間で脱バイ焼成した。Next, the laminated ceramic green chips 105 were subjected to debye firing as shown in the temperature diagram of FIG. 1 while flowing 100 liters of nitrogen gas per minute using a batch type atmosphere furnace. In order to confirm the effect of the present invention, as shown in (Table 1), the maximum temperature 60
Debye baking was performed at 0 ° C. and a holding time of 5 hours.
【００３０】[0030]
【表１】 [Table 1]
【００３１】その後、脱バイ焼成に用いたのと同様のバ
ッチ式雰囲気炉を用いて、６００℃までは窒素ガスを毎
分５０リットル流しながら、６００から１３００℃まで
は窒素ガスを毎分５０リットルと水素ガスを毎分０．２
〜２リットル流しながら、１３００℃で２時間焼成し、
外部電極１０６，１０７を形成して積層セラミックコン
デンサ１０１を得た。前記積層セラミックコンデンサ１
０１の構造欠陥の発生状況、及び絶縁抵抗の寿命試験
（１２５℃，ＤＣ３２Ｖ−２５０ｈｒ印加）の結果を前
記（表１）に併せて示す。（表１）において構造欠陥の
発生状況はそれぞれ５００個の試料についての発生状況
を示し、また絶縁抵抗の寿命試験結果は初期値が１×１
０9以上の５０個の試料が試験後に１×１０7以下になっ
た個数を示している。尚、＃を付した試料５は本発明の
範囲外で比較例である。Then, using the same batch type atmosphere furnace as that used for de-baking firing, nitrogen gas was flowed at 50 liters per minute up to 600 ° C., and nitrogen gas was 50 liters per minute up to 600 to 1300 ° C. And hydrogen gas 0.2 per minute
Bake at ~ 2300 for 2 hours at 1300 ° C,
External electrodes 106 and 107 were formed to obtain a monolithic ceramic capacitor 101. The multilayer ceramic capacitor 1
The occurrence status of structural defects of No. 01 and the result of the insulation resistance life test (125 ° C., DC32V-250 hr application) are also shown in (Table 1) above. In Table 1, the occurrence status of structural defects is shown for each of 500 samples, and the insulation resistance life test result has an initial value of 1 × 1.
The number of 50 samples of 0 9 or more that became 1 × 10 7 or less after the test is shown. Incidentally, Sample 5 with # is a comparative example outside the scope of the present invention.
【００３２】（表１）に示したように、本発明の製造方
法による積層セラミックコンデンサ１０１は、ヒビやク
ラックといった構造欠陥の発生がなく、また絶縁抵抗が
劣化したものは僅かであるのに対し、比較例＃５では構
造欠陥及び絶縁抵抗の劣化が多発し正規の特性が得られ
ていないことがわかる。特に２０℃〜４００℃の昇温速
度を２５℃／Ｈｒ以下とするとヒビやクラックといった
構造欠陥の抑制効果が大きく、４００℃〜６００℃の昇
温速度を２０℃／Ｈｒ以下とすると絶縁抵抗劣化の抑制
効果が大きい。これは内部電極１０３，１０４となるニ
ッケル電極ペースト中に含まれる溶剤、樹脂、可塑剤は
２０℃〜４００℃の温度範囲において分解除去され、さ
らに４００℃〜６００℃の温度範囲においては誘電体層
となるグリーンシート１０２中に含まれるポリエチレン
が分解除去されることから、それらの分解が盛んな温度
範囲の昇温をゆっくり行うことにより、有機バインダー
の除去を容易にし、さらに急激な分解を避けつつ徐々に
十分分解除去し、最終の焼結体内部にカーボンが残留す
ることを防止することができるという作用によるもので
ある。中でも特に、誘電体層となるグリーンシート１０
２中に含まれるポリエチレンは、４００℃〜４５０℃の
ごとく狭い温度範囲においてその大部分が急激に分解除
去されるため、その温度範囲の昇温をさらにゆっくり行
うことがより効果的であった。As shown in (Table 1), in the laminated ceramic capacitor 101 manufactured by the method of the present invention, structural defects such as cracks and cracks are not generated, and the insulation resistance is deteriorated. In Comparative Example # 5, it can be seen that structural defects and insulation resistance deterioration frequently occur and normal characteristics are not obtained. In particular, if the heating rate of 20 ° C to 400 ° C is 25 ° C / Hr or less, the effect of suppressing structural defects such as cracks and cracks is large, and if the heating rate of 400 ° C to 600 ° C is 20 ° C / Hr or less, insulation resistance deterioration Has a large effect of suppressing. This is because the solvent, resin, and plasticizer contained in the nickel electrode paste to be the internal electrodes 103 and 104 are decomposed and removed in the temperature range of 20 ° C to 400 ° C, and the dielectric layer is further removed in the temperature range of 400 ° C to 600 ° C. Since the polyethylene contained in the green sheet 102 is decomposed and removed, the organic binder is easily removed by slowly raising the temperature in a temperature range in which the decomposition is active, while avoiding further rapid decomposition. This is because the carbon can be gradually decomposed and removed sufficiently to prevent carbon from remaining inside the final sintered body. Above all, the green sheet 10 which becomes the dielectric layer is particularly preferable.
Since most of the polyethylene contained in 2 is rapidly decomposed and removed in a narrow temperature range such as 400 ° C. to 450 ° C., it is more effective to raise the temperature in that temperature range more slowly.
【００３３】以上の結果から本発明の製造方法は歩留お
よび製品特性を向上させるのに有効な手段であることが
明らかである。From the above results, it is clear that the production method of the present invention is an effective means for improving the yield and product characteristics.
【００３４】尚、絶縁劣化しなかった試料と、絶縁劣化
した試料を分析した結果、絶縁劣化した試料からは残留
カーボンが検出された。尚、本実施の形態１では、６０
０℃までは窒素ガスを、６００から１３００℃までは窒
素ガスと水素ガスとの混合ガスを用いたが、６００℃ま
でを窒素ガス、水素ガス、炭酸ガス、水蒸気の何れかの
雰囲気中で、６００から１３００℃の範囲を窒素ガス、
水素ガス、炭酸ガス、水蒸気の中から選ばれた２つ以上
のガスを所定の割合で混合したものを用いた場合におい
ても同様な結果が得られた。また窒素ガス、水素ガス、
炭酸ガス、水蒸気の混合ガスを用いるのは精度良く酸素
分圧を容易に制御することができるためである。また有
機結合材成分として、重量平均分子量が４００，０００
以上の超高分子ポリエチレンを用いた例を説明したが、
これに限定されるものではなく、他の有機結合材を用い
た場合でも同様の効果が得られる。また、本実施の形態
１では積層セラミックコンデンサを例に説明したが、こ
れに限定されるものではなく、他の電子部品例えば積層
アクチュエータ、積層バリスタなどに適用しても同様の
効果が得られる。As a result of analyzing the sample which did not have insulation deterioration and the sample which had insulation deterioration, residual carbon was detected from the sample having insulation deterioration. In the first embodiment, 60
Nitrogen gas was used up to 0 ° C., and a mixed gas of nitrogen gas and hydrogen gas was used from 600 to 1300 ° C., but up to 600 ° C. in an atmosphere of nitrogen gas, hydrogen gas, carbon dioxide gas, or steam, Nitrogen gas in the range of 600 to 1300 ° C,
Similar results were obtained when a mixture of two or more gases selected from hydrogen gas, carbon dioxide gas and steam at a predetermined ratio was used. In addition, nitrogen gas, hydrogen gas,
The mixed gas of carbon dioxide and water vapor is used because the oxygen partial pressure can be easily controlled with high accuracy. As the organic binder component, the weight average molecular weight is 400,000.
An example using the above ultra high molecular weight polyethylene has been described,
The present invention is not limited to this, and the same effect can be obtained even when another organic binder is used. Further, although the first embodiment has been described by taking the laminated ceramic capacitor as an example, the present invention is not limited to this, and the same effect can be obtained by applying it to other electronic components such as a laminated actuator and a laminated varistor.
【００３５】（実施の形態２）以下、実施の形態２を用
いて本発明の特に請求項２及び請求項３に記載の発明に
ついて、実施の形態１と同様に積層セラミック電子部品
の代表として前記積層セラミックコンデンサ１０１を例
にとり説明する。(Embodiment 2) Hereinafter, with reference to Embodiment 2 of the present invention, the invention described in claim 2 and claim 3 will be described as a representative of a laminated ceramic electronic component as in Embodiment 1. The multilayer ceramic capacitor 101 will be described as an example.
【００３６】図２は本発明の実施の形態２における脱バ
イ焼成の温度図である。FIG. 2 is a temperature diagram of the debye firing in the second embodiment of the present invention.
【００３７】まず、熱処理に用いたのと同様のバッチ式
雰囲気炉を用いて、実施の形態１で作製した積層セラミ
ックグリーンチップ１０５を投入し、次いで、前記積層
セラミックグリーンチップ１０５をバッチ式雰囲気炉を
用いて、窒素ガスを毎分１００リットル流しながら、図
２の温度図に示すように脱バイ焼成を行った。尚、本発
明の効果を確認するために（表２）に示すように昇温速
度を変えて最高温度６００℃、保持時間５時間で脱バイ
焼成し、その後、実施の形態１と同様に、１３００℃で
２時間焼成し、外部電極１０６，１０７を形成して積層
セラミックコンデンサ１０１を作製した。First, using the same batch type atmospheric furnace as that used for the heat treatment, the laminated ceramic green chips 105 produced in the first embodiment are charged, and then the laminated ceramic green chips 105 are put into the batch type atmospheric furnace. 2 was used to perform de-by-baking as shown in the temperature diagram of FIG. 2 while flowing 100 liters of nitrogen gas per minute. In order to confirm the effect of the present invention, as shown in (Table 2), the temperature rising rate was changed, the maximum temperature was 600 ° C., the holding time was 5 hours, and de-baking was performed, and thereafter, as in the first embodiment, By firing at 1300 ° C. for 2 hours, external electrodes 106 and 107 were formed, and a monolithic ceramic capacitor 101 was produced.
【００３８】[0038]
【表２】 [Table 2]
【００３９】前記積層セラミックコンデンサの構造欠陥
の発生状況及び絶縁抵抗の寿命試験（１２５℃，ＤＣ３
２Ｖ−２５０ｈｒ印加）の結果を（表２）に併せて示
す。（表２）において構造欠陥の発生状況はそれぞれ５
００個の試料についての発生状況を示し、また絶縁抵抗
の寿命試験結果は初期値が１×１０9以上の５０個の試
料が試験後に１×１０7以下になった個数を示してい
る。尚、＃を付した試料は本発明の範囲外で比較例であ
る。Occurrence of structural defects and life test of insulation resistance (125 ° C., DC3
The results of 2V-250 hr application) are also shown in (Table 2). In Table 2, the occurrence status of structural defects is 5 each.
The occurrence status of 00 samples is shown, and the result of the insulation resistance life test shows the number of 50 samples having an initial value of 1 × 10 9 or more and 1 × 10 7 or less after the test. Samples marked with # are comparative examples outside the scope of the present invention.
【００４０】（表２）に示したように、本発明の製造方
法による積層セラミックコンデンサ１０１は、ヒビやク
ラックといった構造欠陥の発生がなく、また絶縁抵抗が
劣化したものは僅かであるのに対し、比較例＃１０では
構造欠陥及び絶縁抵抗の劣化が多発し正規の特性が得ら
れていないことがわかる。これは内部電極１０３，１０
４となるニッケル電極ペースト中に含まれる溶剤、樹
脂、可塑剤は２０℃〜４００℃の温度範囲において分解
除去され、さらに４００℃〜６００℃の温度範囲におい
ては誘電体層となるセラミックシート中に含まれるポリ
エチレンが分解除去されることから、それらの分解が盛
んな温度範囲の昇温をゆっくり行うことにより、有機バ
インダーの除去を容易にし、さらに急激な分解を避けつ
つ徐々に十分分解除去し、最終の焼結体内部にカーボン
が残留することを防止することができるという作用によ
るものである。中でも特に、誘電体層となるグリーンシ
ート１０２中に含まれるポリエチレンは、４００℃〜４
５０℃のごく狭い温度範囲においてその大部分が急激に
分解除去されるため、その温度範囲の昇温をさらにゆっ
くり行うことがより効果的であった。As shown in (Table 2), in the laminated ceramic capacitor 101 manufactured by the manufacturing method of the present invention, structural defects such as cracks and cracks are not generated, and the insulation resistance is deteriorated in a few cases. In Comparative Example # 10, it can be seen that structural defects and insulation resistance deterioration frequently occur and normal characteristics are not obtained. This is the internal electrode 103, 10
The solvent, resin, and plasticizer contained in the nickel electrode paste to be No. 4 are decomposed and removed in the temperature range of 20 ° C to 400 ° C, and further in the ceramic sheet to be the dielectric layer in the temperature range of 400 ° C to 600 ° C. Since the contained polyethylene is decomposed and removed, the organic binder is easily removed by slowly raising the temperature in a temperature range where the decomposition is active, and the organic binder is gradually decomposed and removed while avoiding rapid decomposition, This is because carbon can be prevented from remaining inside the final sintered body. Above all, polyethylene contained in the green sheet 102, which becomes the dielectric layer, is 400 ° C. to 4 ° C.
Since most of it is rapidly decomposed and removed in a very narrow temperature range of 50 ° C., it was more effective to raise the temperature in that temperature range more slowly.
【００４１】以上の結果から本発明の製造方法は歩留お
よび製品特性を向上させるのに有効な手段であることが
明らかである。From the above results, it is clear that the production method of the present invention is an effective means for improving the yield and product characteristics.
【００４２】尚、絶縁劣化しなかった試料と、絶縁劣化
した試料を分析した結果、絶縁劣化した試料からは残留
カーボンが検出された。尚、本実施の形態２では、６０
０℃までは窒素ガスを、６００から１３００℃までは窒
素ガスと水素ガスとの混合ガスを用いたが、６００℃ま
でを窒素ガス、水素ガス、炭酸ガス、水蒸気の何れかの
雰囲気中で、６００から１３００℃の範囲を窒素ガス、
水素ガス、炭酸ガス、水蒸気の中から選ばれた２つ以上
のガスを所定の割合で混合したものを用いた場合におい
ても同様な結果が得られた。また窒素ガス、水素ガス、
炭酸ガス、水蒸気の混合ガスを用いるのは精度良く酸素
分圧を容易に制御することができるためである。また有
機結合材成分として、重量平均分子量が４００，０００
以上の超高分子ポリエチレンを用いた例を説明したが、
これに限定されるものではなく、他の有機結合材を用い
た場合でも同様の効果が得られる。また更に、積層セラ
ミックコンデンサを例に説明したが、これに限定される
ものではなく、他の電子部品例えば積層アクチュエー
タ、積層バリスタなどに適用しても同様の効果が得られ
る。As a result of analyzing the sample which did not have insulation deterioration and the sample which had insulation deterioration, residual carbon was detected from the sample having insulation deterioration. In the second embodiment, 60
Nitrogen gas was used up to 0 ° C., and a mixed gas of nitrogen gas and hydrogen gas was used from 600 to 1300 ° C., but up to 600 ° C. in an atmosphere of nitrogen gas, hydrogen gas, carbon dioxide gas, or steam, Nitrogen gas in the range of 600 to 1300 ° C,
Similar results were obtained when a mixture of two or more gases selected from hydrogen gas, carbon dioxide gas and steam at a predetermined ratio was used. In addition, nitrogen gas, hydrogen gas,
The mixed gas of carbon dioxide and water vapor is used because the oxygen partial pressure can be easily controlled with high accuracy. As the organic binder component, the weight average molecular weight is 400,000.
An example using the above ultra high molecular weight polyethylene has been described,
The present invention is not limited to this, and the same effect can be obtained even when another organic binder is used. Furthermore, although the multilayer ceramic capacitor has been described as an example, the present invention is not limited to this, and the same effect can be obtained by applying it to other electronic components such as a multilayer actuator and a multilayer varistor.
【００４３】[0043]
【発明の効果】本発明の積層セラミック電子部品の製造
方法によれば、積層セラミックグリーンチップを常温〜
略１３００℃の焼成温度まで昇温し脱バイ焼成する際
に、前記焼成温度の２０℃〜４００℃の昇温範囲では、
その昇温速度を２５℃／Ｈｒ以下とすることにより、グ
リーンシートやＮｉを主成分とする内部電極中に含まれ
る可塑剤を、急激な分解を避けつつ徐々に十分分解除去
し、その後の有機バインダーの分解除去が十分に行われ
焼結体内部にカーボンが残留することを防止することが
できる。従って、この製造方法によって得られた積層セ
ラミック電子部品は、信頼性の高い安定した性能を再現
性良く生産することができるという効果を有する。According to the method of manufacturing a monolithic ceramic electronic component of the present invention, the monolithic ceramic green chip is kept at room temperature to room temperature.
When the temperature is raised to a firing temperature of approximately 1300 ° C. and debye firing is performed, the firing temperature is in the range of 20 ° C. to 400 ° C.
By setting the temperature rising rate to 25 ° C./Hr or less, the plasticizer contained in the green sheet or the internal electrode containing Ni as a main component is gradually decomposed and removed while avoiding rapid decomposition, and the organic layer It is possible to sufficiently decompose and remove the binder and prevent carbon from remaining inside the sintered body. Therefore, the monolithic ceramic electronic component obtained by this manufacturing method has an effect that reliable and stable performance can be produced with good reproducibility.
【図１】本発明の実施の形態１の積層セラミック電子部
品の製造方法における脱バイ焼成の温度図FIG. 1 is a temperature diagram of debye firing in a method for manufacturing a monolithic ceramic electronic component according to a first embodiment of the present invention.
【図２】本発明の実施の形態２の積層セラミック電子部
品の製造方法における脱バイ焼成の温度図FIG. 2 is a temperature diagram of debye firing in the method for manufacturing a monolithic ceramic electronic component according to the second embodiment of the present invention.
【図３】従来例における脱バイ焼成の温度図FIG. 3 is a temperature diagram of de-baking firing in a conventional example.
【図４】積層セラミックグリーンチップの一部切欠斜視
図FIG. 4 is a partially cutaway perspective view of a laminated ceramic green chip.
１０１ 積層セラミックコンデンサ １０２ グリーンシート １０３，１０４ 内部電極 １０５ 積層セラミックグリーンチップ １０６，１０７ 外部電極 101 Multilayer Ceramic Capacitor 102 green sheets 103, 104 internal electrodes 105 Multilayer Ceramic Green Chip 106,107 external electrodes
Claims (8)
混合して形成したグリーンシートとＮｉを主成分とする
内部電極とを積層した積層セラミックグリーンチップを
常温〜略１３００℃の焼成温度まで昇温し脱バイ焼成す
る際に、前記焼成温度の２０℃〜４００℃の昇温範囲で
はその昇温速度を２５℃／Ｈｒ以下とする積層セラミッ
ク電子部品の製造方法。1. A laminated ceramic green chip in which a green sheet formed by mixing a ceramic raw material and an organic binder component and an internal electrode containing Ni as a main component are laminated is heated from room temperature to about 1300 ° C. Then, the method for manufacturing a monolithic ceramic electronic component in which the temperature rising rate is set to 25 ° C./Hr or less in the temperature rising range of 20 ° C. to 400 ° C. at the time of debye firing.
混合して形成したグリーンシートとＮｉを主成分とする
内部電極とを積層した積層セラミックグリーンチップを
常温〜略１３００℃の焼成温度まで昇温し脱バイ焼成す
る際に、前記焼成温度の４００℃〜６００℃の昇温範囲
ではその昇温速度を２０℃／Ｈｒ以下とする積層セラミ
ック電子部品の製造方法。2. A laminated ceramic green chip in which a green sheet formed by mixing a ceramic raw material and an organic binder component and an internal electrode containing Ni as a main component are laminated is heated from room temperature to about 1300 ° C. A method for manufacturing a monolithic ceramic electronic component in which the temperature rising rate is set to 20 ° C./Hr or less in the temperature rising range of 400 ° C. to 600 ° C. of the firing temperature.
囲では、その昇温速度を１０℃／Ｈｒ以下とする請求項
１または２に記載の積層セラミック電子部品の製造方
法。3. The method for producing a monolithic ceramic electronic component according to claim 1, wherein the heating rate is 10 ° C./Hr or less in the firing temperature range of 400 ° C. to 450 ° C.
囲では、その昇温速度を２０℃／Ｈｒ以下とする請求項
１または２に記載の積層セラミック電子部品の製造方
法。4. The method for producing a monolithic ceramic electronic component according to claim 1, wherein the temperature rising rate is 20 ° C./Hr or less in the firing temperature range of 400 ° C. to 600 ° C.
囲では、その昇温速度を２０℃／Ｈｒ以下とし、この昇
温範囲の４００℃〜４５０℃の範囲では、その昇温速度
を１０℃／Ｈｒ以下とする請求項１または２に記載の積
層セラミック電子部品の製造方法。5. The heating rate is set to 20 ° C./Hr or less in the heating temperature range of 400 ° C. to 600 ° C., and the heating rate is set in the heating temperature range of 400 ° C. to 450 ° C. The method for producing a monolithic ceramic electronic component according to claim 1, wherein the temperature is 10 ° C./Hr or less.
の中から選ばれたガス雰囲気及びこれらの中から２つ以
上選ばれたガス雰囲気中で脱バイ焼成を行う請求項１ま
たは２に記載の積層セラミック電子部品の製造方法。6. The debye firing is performed in a gas atmosphere selected from nitrogen gas, hydrogen gas, carbon dioxide gas, and steam, and in a gas atmosphere selected from two or more of these. Manufacturing method of multilayer ceramic electronic component.
以上のポリオレフィンである請求項１または２に記載の
積層セラミック電子部品の製造方法。7. The method for producing a laminated ceramic electronic component according to claim 1, wherein the organic binder component is a polyolefin having a weight average molecular weight of 400,000 or more.
ニルアルコール及びそれらの共重合体からなる群より選
ばれる少なくとも一種のポリオレフィンである請求項７
に記載の積層セラミック電子部品の製造方法。8. The polyolefin is at least one polyolefin selected from the group consisting of polyethylene, polyvinyl alcohol and copolymers thereof.
A method for manufacturing a monolithic ceramic electronic component according to.
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| JP2001317791A JP2003124054A (en) | 2001-10-16 | 2001-10-16 | Method of manufacturing laminated ceramic electronic part |
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| KR100741835B1 (en) | 2005-06-24 | 2007-07-24 | 삼성전기주식회사 | High-speed rising temperature plasticity method of multi layer chip |
| WO2019167753A1 (en) * | 2018-03-01 | 2019-09-06 | 日本碍子株式会社 | Method for degreasing ceramic molded body and method for manufacturing ceramic sintered body |
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2001
- 2001-10-16 JP JP2001317791A patent/JP2003124054A/en active Pending
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| KR100741835B1 (en) | 2005-06-24 | 2007-07-24 | 삼성전기주식회사 | High-speed rising temperature plasticity method of multi layer chip |
| JP2007039486A (en) * | 2005-08-01 | 2007-02-15 | Toray Ind Inc | Heat-resistant resin precursor composition and semiconductor device using the same |
| WO2019167753A1 (en) * | 2018-03-01 | 2019-09-06 | 日本碍子株式会社 | Method for degreasing ceramic molded body and method for manufacturing ceramic sintered body |
| CN111417612A (en) * | 2018-03-01 | 2020-07-14 | 日本碍子株式会社 | Method for degreasing ceramic molded body and method for producing ceramic fired body |
| KR20200111785A (en) | 2018-03-01 | 2020-09-29 | 엔지케이 인슐레이터 엘티디 | Degreasing method of ceramic molded body and manufacturing method of ceramic fired body |
| JPWO2019167753A1 (en) * | 2018-03-01 | 2021-02-25 | 日本碍子株式会社 | Solventing method of ceramic molded body and manufacturing method of ceramic fired body |
| KR102441214B1 (en) | 2018-03-01 | 2022-09-06 | 엔지케이 인슐레이터 엘티디 | Degreasing method of ceramic compact and manufacturing method of ceramic sintered body |
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| CN117079974B (en) * | 2023-09-28 | 2024-04-26 | 潮州三环（集团）股份有限公司 | Glue discharging method of ceramic green body and preparation method of multilayer ceramic capacitor |
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