JPH01108716A - Laminated ceramic capacitor - Google Patents
Laminated ceramic capacitorInfo
- Publication number
- JPH01108716A JPH01108716A JP62267300A JP26730087A JPH01108716A JP H01108716 A JPH01108716 A JP H01108716A JP 62267300 A JP62267300 A JP 62267300A JP 26730087 A JP26730087 A JP 26730087A JP H01108716 A JPH01108716 A JP H01108716A
- Authority
- JP
- Japan
- Prior art keywords
- ceramic
- capacitor
- materials
- ceramic layer
- ceramic capacitor
- 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.)
- Granted
Links
- 239000003985 ceramic capacitor Substances 0.000 title claims abstract description 27
- 239000000919 ceramic Substances 0.000 claims abstract description 47
- 239000002131 composite material Substances 0.000 claims abstract description 21
- 239000006104 solid solution Substances 0.000 claims abstract description 3
- 239000000463 material Substances 0.000 abstract description 21
- 239000003990 capacitor Substances 0.000 abstract description 16
- 229910052573 porcelain Inorganic materials 0.000 abstract description 6
- 238000006243 chemical reaction Methods 0.000 abstract description 5
- 238000000034 method Methods 0.000 abstract description 4
- 238000010030 laminating Methods 0.000 abstract description 2
- 238000005245 sintering Methods 0.000 abstract description 2
- 230000035699 permeability Effects 0.000 abstract 2
- 230000003287 optical effect Effects 0.000 abstract 1
- 239000010410 layer Substances 0.000 description 21
- 230000000694 effects Effects 0.000 description 5
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 4
- 238000009792 diffusion process Methods 0.000 description 4
- 239000000203 mixture Substances 0.000 description 3
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 2
- 229910002113 barium titanate Inorganic materials 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 230000001681 protective effect Effects 0.000 description 2
- 239000011241 protective layer Substances 0.000 description 2
- 239000002002 slurry Substances 0.000 description 2
- FKSZLDCMQZJMFN-UHFFFAOYSA-N [Mg].[Pb] Chemical compound [Mg].[Pb] FKSZLDCMQZJMFN-UHFFFAOYSA-N 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- JRPBQTZRNDNNOP-UHFFFAOYSA-N barium titanate Chemical compound [Ba+2].[Ba+2].[O-][Ti]([O-])([O-])[O-] JRPBQTZRNDNNOP-UHFFFAOYSA-N 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- PMHQVHHXPFUNSP-UHFFFAOYSA-M copper(1+);methylsulfanylmethane;bromide Chemical compound Br[Cu].CSC PMHQVHHXPFUNSP-UHFFFAOYSA-M 0.000 description 1
- 239000003989 dielectric material Substances 0.000 description 1
- NKZSPGSOXYXWQA-UHFFFAOYSA-N dioxido(oxo)titanium;lead(2+) Chemical compound [Pb+2].[O-][Ti]([O-])=O NKZSPGSOXYXWQA-UHFFFAOYSA-N 0.000 description 1
- 238000007606 doctor blade method Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 229910052763 palladium Inorganic materials 0.000 description 1
- 238000007650 screen-printing Methods 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000004332 silver Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
Landscapes
- Ceramic Capacitors (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、積層セラミック・コンデンサに関し、特に誘
電率の温度変化が少なく、かつ高誘電率のコンデンサに
関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a multilayer ceramic capacitor, and particularly to a capacitor having a high dielectric constant and a small change in dielectric constant due to temperature.
電子部品の基板上への実装密度が高まるにつれ、コンデ
ンサ等の電子部品のチップ化が盛んになってきているが
、コンデンサチップ市場では温度特性変化の小さなＸ７
Ｒ特性が大半を占めている。従来の高誘電率磁器組成物
材料としてはチタン酸バリウム（ＢａＴｉＯ３）系が知
られており、添加や置換によってキュリー点を移動させ
て温度特性改善をはかっている。As the mounting density of electronic components on substrates increases, the use of chips for electronic components such as capacitors has become popular, but in the capacitor chip market,
The R characteristic occupies the majority. Barium titanate (BaTiO3) is known as a conventional high dielectric constant ceramic composition material, and its Curie point is moved by addition or substitution to improve temperature characteristics.
この従来の方法により、Ｘ７Ｒ特性を実現した場合、得
られる誘電率は高々２０００程度に過ぎず、チップの軽
薄短小化の要求に適合しなかった。これを解決する手段
として、キュリー点が異なった高い誘電率を持つ磁器組
成物材料を組み合わせ、温度特性の優れた大容量コンデ
ンサを実現する製造方法が提案されたが、実際には組合
わせた異種磁器組成物材料間に拡散反応が起こりキュリ
ー点が一つとなり温度特性改善効果はあまり望めなかっ
た。When X7R characteristics were achieved using this conventional method, the dielectric constant obtained was only about 2000 at most, which did not meet the requirements for making chips lighter, thinner, shorter and smaller. As a means to solve this problem, a manufacturing method has been proposed in which a large capacity capacitor with excellent temperature characteristics is created by combining ceramic composition materials with different Curie points and high dielectric constants. Diffusion reactions occurred between the materials of the ceramic composition, resulting in a single Curie point, and no significant improvement in temperature characteristics could be expected.
本発明の目的は、上述の要請に鑑み、誘電率が高く、か
つ温度変化率の小さい優れた電気特性を有することので
きる積層セラミック・コンデンサを提供することにある
。In view of the above requirements, an object of the present invention is to provide a multilayer ceramic capacitor that has a high dielectric constant and excellent electrical characteristics with a small rate of temperature change.
本発明の積層セラミック・コンデンサは、セラミック誘
電体層と内部電極が交互に積層して成る積層セラミック
・コンデンサにおいて、前記セラミック誘電体層がキュ
リー点の異る少くとも二種項の磁器組成物材料で形成さ
れ、かつ、複数の前記セラミック誘電体層°の間に３乃
至３０μｍの前記磁器組成物材料と固溶しにくいセラミ
ック層が形成されている。The multilayer ceramic capacitor of the present invention is a multilayer ceramic capacitor in which ceramic dielectric layers and internal electrodes are alternately laminated, wherein the ceramic dielectric layers are made of at least two types of ceramic composition materials having different Curie points. A ceramic layer having a thickness of 3 to 30 μm that is difficult to form a solid solution with the ceramic composition material is formed between the plurality of ceramic dielectric layers.
キュリー点の異なる磁器組成物材料間に３乃至１０μｍ
のセラミック層を介在させることにより、焼結過程にお
ける拡散反応を防止できる。そのため個々の材料のキュ
リー点を変えることなく複合化でき、任意のキュリー点
°を待った材料を組み合わせ積層することにより、誘電
率が高く、かつ、温度による容量変化の小さなコンデン
サを実現できる。3 to 10 μm between porcelain composition materials with different Curie points
By interposing the ceramic layer, diffusion reactions during the sintering process can be prevented. Therefore, it is possible to combine individual materials without changing their Curie points, and by combining and laminating materials with arbitrary Curie points, it is possible to create capacitors with a high dielectric constant and a small change in capacitance due to temperature.
次に、本発明の実施例について図面を参照して説明する
。Next, embodiments of the present invention will be described with reference to the drawings.
第１図（ａ）、（ｂ）は本発明の積層セラミック・コン
デンサチップの内部電極の積層構造の第１の実施例を示
す斜視図及び積層セラミック・コデンサの斜視図、第２
図（ａ）、（ｂ）は本実施例の内部電極及びセラミック
層形成材料をセラミックグリーンシートに被着したとき
の断面図、第３図（ａ）、（ｂ）は本実施例の積層構造
を説明するための斜視図及び断面図、第４図は本実施例
の積層セラミック・コンデンサと従来の積層セラミック
・コンデンサの温度による容量変化率を示す特性図、第
５図は本発明の積層セラミック・コンデンサチップの内
部電極の積層構造の第２の実施例を示す斜視図である。FIGS. 1(a) and 1(b) are a perspective view showing a first embodiment of the multilayer structure of the internal electrode of the multilayer ceramic capacitor chip of the present invention, a perspective view of the multilayer ceramic capacitor, and a second embodiment of the multilayer ceramic capacitor chip.
Figures (a) and (b) are cross-sectional views when the internal electrode and ceramic layer forming material of this example are adhered to a ceramic green sheet, and Figures 3 (a) and (b) are the laminated structure of this example. FIG. 4 is a characteristic diagram showing the rate of change in capacitance due to temperature of the multilayer ceramic capacitor of this embodiment and a conventional multilayer ceramic capacitor, and FIG. 5 is a perspective view and a cross-sectional view for explaining the multilayer ceramic capacitor of the present invention. - It is a perspective view showing a second example of a laminated structure of internal electrodes of a capacitor chip.
以下、実施例に従って本発明の詳細な説明を行う。マグ
ネシウム・タングステン酸鉛Ｐｂ（Ｍ ｇ １／２ Ｗ
ｌ／２ ） Ｏ３とチタン酸鉛ＰｂＴｉ０□を所定のキ
ュリー点が得られるように所定の割合で混合した組成物
材料を複数用いて積層セラミック・コンデンサを製作し
た。Hereinafter, the present invention will be explained in detail according to Examples. Magnesium lead tungstate Pb (M g 1/2 W
A multilayer ceramic capacitor was manufactured using a plurality of composition materials in which O3 and lead titanate (PbTi0□) were mixed at a predetermined ratio so as to obtain a predetermined Curie point.
第１の実施例は２種類の磁器組成物材料をセラミック層
を介して組合せた例である。The first example is an example in which two types of ceramic composition materials are combined via a ceramic layer.
各組成物材料の予焼粉末と有機バインダー、有機溶媒と
を混合し、泥漿を作製した。この泥漿をドクターブレー
ド法でフィルム上に数１０μｍの厚さにキャスティング
しグリーンシートを作製した。このシートを乾燥し、フ
ィルムから剥離し、所定の形状に切断した後、第２図（
ａ）の如く銀・パラジウムペーストを片面に印刷した。Prefired powder of each composition material, an organic binder, and an organic solvent were mixed to prepare a slurry. This slurry was cast onto a film to a thickness of several tens of micrometers using a doctor blade method to produce a green sheet. After drying this sheet, peeling it off from the film and cutting it into a predetermined shape, the sheet is shown in Figure 2 (
Silver/palladium paste was printed on one side as in a).
またセラミック層を形成するために、第２図（ｂ）の如
く所定のセラミック層形成材料１３をグリーンシート上
にスクリーン印刷法によって１０μｍの厚さに印刷した
。セラミック層形成材料はジルコニアの粉末を有機ビヒ
クルを混合したペーストを用いて印刷した。In order to form a ceramic layer, a predetermined ceramic layer forming material 13 was printed on a green sheet to a thickness of 10 μm by screen printing as shown in FIG. 2(b). The ceramic layer forming material was printed using a paste containing zirconia powder mixed with an organic vehicle.
これらのシートを第３図（ａ）に示すように、保護層用
シート４ａ、電極形成用シート４ｂ、セラミック層形成
材料用シート４ｃ、４ａとは異なる材料の電極形成用シ
ート５ｂ、４ａとは異なる材料の保護層用シー）５ａの
順に所定の組合せに従って数１０枚積層、圧着し、積層
体の断面を示す第３図（ｂ）の切断位置６で所定の形状
に切断し、空気中にて９５０℃で焼成して第１図（ａ）
に示すような磁器組成物材料と反応しにくいセラミック
層のある積層セラミック・コンデンサチップを得た０次
に、外部電極を形成し、第１図（ｂ）に示す積層セラミ
ック・コンデンサを得た。As shown in FIG. 3(a), these sheets are a protective layer sheet 4a, an electrode forming sheet 4b, a ceramic layer forming material sheet 4c, and an electrode forming sheet 5b made of a material different from 4a. Several dozen sheets of protective layer sheet) 5a made of different materials are stacked and crimped according to a predetermined combination, cut into a predetermined shape at cutting position 6 in FIG. 3(b) showing the cross section of the laminate, and placed in air. Figure 1(a)
A multilayer ceramic capacitor chip having a ceramic layer that does not easily react with the ceramic composition material as shown in FIG. 1 was obtained. Next, external electrodes were formed to obtain a multilayer ceramic capacitor shown in FIG.
第４図は従来構造を用い異種磁器組成物材料を組合せた
積層コンデンサチップと本実施例の異種磁器組成物材料
を組合せた積層コンデンサチップの容量の温度変化率の
特性線Ｃ，Ｂを示した。また参考として各磁器組成物材
料単独の従来の構造のコンデンサチップの容量の温度変
化率の特性Ａ、Ｄも示した。従来の構造によるコンデン
サは、組合せた組成１料間に拡散反応が起こり、単一組
成物となりキュリー点が−っになってしまっているのに
対し、本発明の構造によるものは、組合せた組成物材料
間で拡散反応が起こらないため各材料の特性によりコン
デンサチップの温度特性が改善されていることがわかる
。Figure 4 shows characteristic lines C and B of the temperature change rate of capacitance of a multilayer capacitor chip with a conventional structure and a combination of different types of ceramic composition materials and a multilayer capacitor chip with a combination of different types of ceramic composition materials of this example. . For reference, characteristics A and D of the temperature change rate of capacitance of a capacitor chip of a conventional structure made of each ceramic composition material alone are also shown. In capacitors with the conventional structure, a diffusion reaction occurs between the combined compositions, resulting in a single composition with a Curie point of -, whereas in the capacitor with the structure of the present invention, the Curie point is - - It can be seen that the temperature characteristics of the capacitor chip are improved due to the characteristics of each material because no diffusion reaction occurs between the materials.
第５図は本発明の第２の実施例の４種類の磁器組成物材
料を磁器組成物材料と反応しにくいセラミック層を介し
て組合せた場合の斜視図である。FIG. 5 is a perspective view of a second embodiment of the present invention in which four types of porcelain composition materials are combined via a ceramic layer that does not easily react with the porcelain composition material.
第１の実施例と同じ方法で異る４種類の電極形成セラミ
ックグリーンシートの間にセラミック層形成材料１３を
被着させたセラミックグリーンシートを挟み、交互に積
層、圧着し、所定の形状に切断し、焼成して第５図に示
すような異種磁器組成物材料間にセラミック層を挟んだ
４層構造の積層セラミック・コンデンサチップを得た。Ceramic green sheets coated with ceramic layer forming material 13 are sandwiched between four different types of electrode-forming ceramic green sheets using the same method as in the first embodiment, alternately laminated and crimped, and cut into a predetermined shape. Then, by firing, a multilayer ceramic capacitor chip having a four-layer structure in which a ceramic layer was sandwiched between different types of ceramic composition materials as shown in FIG. 5 was obtained.
この第２の実施例においても、第１の実施例と同様な効
果を得ることが出来る。In this second embodiment as well, the same effects as in the first embodiment can be obtained.
また、本発明の実施例には誘電体材料と反応しにくいジ
ルコニアを用いたが、アルミナや窒化アルミニウムを用
いても同様の効果が得られる。Furthermore, although zirconia, which does not easily react with dielectric materials, was used in the embodiments of the present invention, similar effects can be obtained by using alumina or aluminum nitride.
第４図に示した例からも明らかなように、本発明の積層
セラミック・コンデンサは、キュリー点の異なる複数の
高誘電率−材料を用い、前記高誘電率材料間に３乃至３
０μｍのセラミック層を介在させることによって温度特
性にすぐれ、かつ、小さな形状で高静電容量を簡単に実
現できる効果がある。As is clear from the example shown in FIG. 4, the multilayer ceramic capacitor of the present invention uses a plurality of high permittivity materials having different Curie points, and has 3 to 3 points between the high permittivity materials.
By interposing the 0 μm ceramic layer, it has the effect of providing excellent temperature characteristics and easily realizing high capacitance with a small shape.
第１図（ａ）、（ｂ）は本発明の積層セラミック・コン
デンサチップの内部電極の積層構造の第１の実施例を示
す斜視図及び積層セラミック・コデンサの斜視図、第２
図（ａ）、（ｂ）は本実施例の内部電極及びセラミック
層形成材料をセラミックグリーンシートに被着したとき
の断面図、第３図（ａ）、（ｂ）は本実施例の積層構造
を説明するための斜視図及び断面図、第４図は本実施例
の積層セラミック・コンデンサと従来の積層セラミック
・コンデンサの温度による容量変化率を示す特性図、第
５図は本発明の積層セラミック・コンデンサチップの内
部電極の積層構造の第２の実施例を示す斜視図である。
１・・・セラミックグリーンシート、２・・・内部電極
、３・・・セラミック層、４ａ・・・保護膜用シート、
４ｂ・・・電極形成用シート、４ｃ・・・セラミック層
形成材料用シート、５ａ・・・保護膜用シート、５ｂ・
・・電極形成用シート、６・・・切断位置、７．８・・
・積層セラミックコンデンサチップ、９・・・積層セラ
ミックコンデンサ、１０・・・外部電極、１３・・・セ
ラミック層形成材料。FIGS. 1(a) and 1(b) are a perspective view showing a first embodiment of the multilayer structure of the internal electrode of the multilayer ceramic capacitor chip of the present invention, a perspective view of the multilayer ceramic capacitor, and a second embodiment of the multilayer ceramic capacitor chip.
Figures (a) and (b) are cross-sectional views when the internal electrode and ceramic layer forming material of this example are adhered to a ceramic green sheet, and Figures 3 (a) and (b) are the laminated structure of this example. FIG. 4 is a characteristic diagram showing the rate of change in capacitance due to temperature of the multilayer ceramic capacitor of this embodiment and a conventional multilayer ceramic capacitor, and FIG. 5 is a perspective view and a cross-sectional view for explaining the multilayer ceramic capacitor of the present invention. - It is a perspective view showing a second example of a laminated structure of internal electrodes of a capacitor chip. DESCRIPTION OF SYMBOLS 1... Ceramic green sheet, 2... Internal electrode, 3... Ceramic layer, 4a... Protective film sheet,
4b... Sheet for electrode formation, 4c... Sheet for ceramic layer forming material, 5a... Sheet for protective film, 5b...
... Sheet for electrode formation, 6... Cutting position, 7.8...
- Multilayer ceramic capacitor chip, 9... Multilayer ceramic capacitor, 10... External electrode, 13... Ceramic layer forming material.
Claims (1)
積層セラミック・コンデンサにおいて、前記セラミック
誘電体層がキュリー点の異る少くとも二種類の磁器組成
物材料で形成され、かつ、複数の前記セラミック誘電体
層の間に３乃至３０μｍの前記磁器組成物材料と固溶し
にくいセラミック層を形成したことを特徴とする積層セ
ラミック・コンデンサ。In a multilayer ceramic capacitor in which ceramic dielectric layers and internal electrodes are alternately laminated, the ceramic dielectric layer is formed of at least two types of ceramic composition materials having different Curie points, and a plurality of the ceramic A multilayer ceramic capacitor characterized in that a ceramic layer having a thickness of 3 to 30 μm and which is difficult to form a solid solution with the ceramic composition material is formed between the dielectric layers.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62267300A JPH01108716A (en) | 1987-10-21 | 1987-10-21 | Laminated ceramic capacitor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62267300A JPH01108716A (en) | 1987-10-21 | 1987-10-21 | Laminated ceramic capacitor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01108716A true JPH01108716A (en) | 1989-04-26 |
| JPH0515294B2 JPH0515294B2 (en) | 1993-03-01 |
Family
ID=17442913
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62267300A Granted JPH01108716A (en) | 1987-10-21 | 1987-10-21 | Laminated ceramic capacitor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01108716A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117585988A (en) * | 2023-11-17 | 2024-02-23 | 江苏师范大学 | A multi-layer composite structure ceramic with high thermal conductivity and high mechanical properties and its preparation method |
-
1987
- 1987-10-21 JP JP62267300A patent/JPH01108716A/en active Granted
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117585988A (en) * | 2023-11-17 | 2024-02-23 | 江苏师范大学 | A multi-layer composite structure ceramic with high thermal conductivity and high mechanical properties and its preparation method |
| CN117585988B (en) * | 2023-11-17 | 2026-04-14 | 江苏师范大学 | High-thermal-conductivity high-mechanical-property multilayer composite structural ceramic and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0515294B2 (en) | 1993-03-01 |
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