JP2735027B2 - Conductive paste for dielectric ceramic capacitors - Google Patents
Conductive paste for dielectric ceramic capacitorsInfo
- Publication number
- JP2735027B2 JP2735027B2 JP10374495A JP10374495A JP2735027B2 JP 2735027 B2 JP2735027 B2 JP 2735027B2 JP 10374495 A JP10374495 A JP 10374495A JP 10374495 A JP10374495 A JP 10374495A JP 2735027 B2 JP2735027 B2 JP 2735027B2
- Authority
- JP
- Japan
- Prior art keywords
- conductive paste
- metal
- dielectric ceramic
- ceramic capacitor
- amount
- 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.)
- Expired - Lifetime
Links
- 239000003985 ceramic capacitor Substances 0.000 title claims description 12
- 229910052751 metal Inorganic materials 0.000 claims description 33
- 239000002184 metal Substances 0.000 claims description 33
- 239000000843 powder Substances 0.000 claims description 15
- 239000000203 mixture Substances 0.000 claims description 11
- 229910052742 iron Inorganic materials 0.000 claims description 10
- 229910052758 niobium Inorganic materials 0.000 claims description 9
- 229910052715 tantalum Inorganic materials 0.000 claims description 9
- 239000011230 binding agent Substances 0.000 claims description 5
- 239000002904 solvent Substances 0.000 claims description 4
- 238000004898 kneading Methods 0.000 claims description 3
- 229910052709 silver Inorganic materials 0.000 claims description 3
- 239000004332 silver Substances 0.000 claims description 3
- 239000003989 dielectric material Substances 0.000 claims 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 11
- 239000010955 niobium Substances 0.000 description 11
- 239000000919 ceramic Substances 0.000 description 9
- 238000005245 sintering Methods 0.000 description 8
- 238000005336 cracking Methods 0.000 description 6
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 5
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 4
- 239000000470 constituent Substances 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 238000010304 firing Methods 0.000 description 3
- 230000001965 increasing effect Effects 0.000 description 3
- 239000011812 mixed powder Substances 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 229910052763 palladium Inorganic materials 0.000 description 2
- 239000001856 Ethyl cellulose Substances 0.000 description 1
- ZZSNKZQZMQGXPY-UHFFFAOYSA-N Ethyl cellulose Chemical compound CCOCC1OC(OC)C(OCC)C(OCC)C1OC1C(O)C(O)C(OC)C(CO)O1 ZZSNKZQZMQGXPY-UHFFFAOYSA-N 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- WUOACPNHFRMFPN-UHFFFAOYSA-N alpha-terpineol Chemical compound CC1=CCC(C(C)(C)O)CC1 WUOACPNHFRMFPN-UHFFFAOYSA-N 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- SQIFACVGCPWBQZ-UHFFFAOYSA-N delta-terpineol Natural products CC(C)(O)C1CCC(=C)CC1 SQIFACVGCPWBQZ-UHFFFAOYSA-N 0.000 description 1
- 230000002542 deteriorative effect Effects 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 229920001249 ethyl cellulose Polymers 0.000 description 1
- 235000019325 ethyl cellulose Nutrition 0.000 description 1
- 230000001939 inductive effect Effects 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 238000010030 laminating Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 230000007847 structural defect Effects 0.000 description 1
- 229940116411 terpineol Drugs 0.000 description 1
- 239000010936 titanium Substances 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 229910052726 zirconium Inorganic materials 0.000 description 1
Landscapes
- Ceramic Capacitors (AREA)
- Fixed Capacitors And Capacitor Manufacturing Machines (AREA)
- Conductive Materials (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は導電性ペーストに関し、
特に積層セラミックコンデンサに用いられる内部電極用
の導電性の金属ペーストに関する。FIELD OF THE INVENTION The present invention relates to a conductive paste.
In particular, the present invention relates to a conductive metal paste for an internal electrode used in a multilayer ceramic capacitor.
【０００２】[0002]
【従来の技術】一般に積層セラミックコンデンサは、セ
ラミック混合粉末を有機バインダと混合してシート上に
加工した後、導電性の金属ペーストを用いて内部電極を
印刷し、これらを積層かつ圧着した後、切断及び焼成を
行ない、外部電極を形成することで製造される。従来、
この種の内部電極に用いられる導電性の金属ペースト
は、銀、パラジウムの金属粉末と有機バインダ及び溶剤
からなるビヒクルにチタンアルコール（特開平４−３１
４７６７）やジルコニウムアルコラート（特開平５−２
５８６０８）を混合し、これを三本ロールミル等により
混練して製造される。2. Description of the Related Art In general, a multilayer ceramic capacitor is prepared by mixing a ceramic mixed powder with an organic binder, processing it on a sheet, printing an internal electrode using a conductive metal paste, and laminating and pressing these electrodes. It is manufactured by cutting and firing to form external electrodes. Conventionally,
The conductive metal paste used for this type of internal electrode is made of a vehicle composed of silver or palladium metal powder, an organic binder and a solvent, and a titanium alcohol (Japanese Patent Laid-Open No. 4-31).
4767) and zirconium alcoholate (Japanese Unexamined Patent Publication No.
58608) and kneading the mixture with a three-roll mill or the like.
【０００３】[0003]
【発明が解決しようとする課題】上述した積層セラミッ
クコンデンサの製造工程において、焼成工程時にセラミ
ック粉末は互いに反応して焼結収縮し、セラミック部の
緻密化がなされる。これと同時に、内部電極として塗布
した導電性ペースト中の金属粉末も焼結収縮し、内部電
極が形成される。しかしながらセラミックと金属は化学
的な結合が起きないため、セラミックと内部電極の結合
は弱く、焼成工程におけるセラミックの焼結収縮と内部
電極中の金属ペーストの焼結収縮の差によって、セラミ
ックと内部電極間の剥離あるいはセラミック内部の応力
によるクラックが発生するという問題があった。また、
ペーストに添加物を加える事によって、剥離、クラック
の発生は制御できたが、焼結性の阻害されて電気的特性
の劣化がおこる問題があった。In the manufacturing process of the above-mentioned multilayer ceramic capacitor, the ceramic powder reacts with each other during the firing process to cause sintering shrinkage, whereby the ceramic portion is densified. At the same time, the metal powder in the conductive paste applied as the internal electrode also undergoes sintering shrinkage, forming an internal electrode. However, since the ceramic and the metal do not chemically bond, the bond between the ceramic and the internal electrode is weak. There has been a problem that cracks occur due to peeling between layers or stress inside the ceramic. Also,
By adding an additive to the paste, peeling and cracking could be controlled, but there was a problem that sinterability was hindered and electrical characteristics were degraded.
【０００４】本発明の目的はセラミックと内部電極間の
接合力を高め、焼結収縮の差により剥離、クラックの発
生を抑制でき、また焼結性の阻害を受けない導電性ペー
ストを提供することにある。[0004] It is an object of the present invention to provide a conductive paste capable of increasing the bonding strength between a ceramic and an internal electrode, suppressing the occurrence of peeling and cracking due to a difference in sintering shrinkage, and not inhibiting sintering properties. It is in.
【０００５】[0005]
【課題を解決するための手段】本発明の導電性ペースト
は、銀を含む金属粉末と誘起バインダと溶剤を混練して
なる誘電体セラミックコンデンサ用導電性ペーストに、
誘電体の構成組成と同一の元素であるＮｂ，Ｆｅ，Ｔａ
のうち少なくとも一つを含む金属アルコラートを含有す
ることを特徴として構成される。この場合、金属アルコ
ラート中のＮｂ，Ｆｅ，Ｔａの量が導電性ペースト中の
金属粉末に対して１．５〜１０．０ｗｔ％の範囲で含有
されることを特徴としている。Means for Solving the Problems The conductive paste of the present invention is a conductive paste for a dielectric ceramic capacitor obtained by kneading a metal powder containing silver, an inducing binder and a solvent.
Nb, Fe, Ta, which is the same element as the constituent composition of the dielectric
And a metal alcoholate containing at least one of the following. In this case, the amount of Nb, Fe, Ta in the metal alcoholate is contained in the range of 1.5 to 10.0 wt% with respect to the metal powder in the conductive paste.
【０００６】[0006]
【実施例】次に本発明について説明する。表１〜３に本
発明による実施例（組成Ａ〜Ｅ）及び従来例（組成Ｆ）
の導電性ペーストの構成を示す。Next, the present invention will be described. Examples according to the present invention (compositions A to E) and conventional examples (composition F) are shown in Tables 1 to 3.
1 shows the configuration of the conductive paste.
【０００７】なお表１〜３で示したパラジウム粉末は粒
径０．１〜０．３μｍ、銀粉は粒径０．２〜０．５μｍ
のものを用いた。一方金属アルコラートは粒径０．２〜
０．５μｍで、ニオブを３４．８ｗｔ％含有するＮｂ
（ＯＣＨ3 （ＣＨ2 ）4 ）2 、鉄を１７．６ｗｔ％含有
するＦｅ（ＯＣＨ3 （ＣＨ2 ）4 ）3 、タンタルを５
１．０ｗｔ％含有するＴａ（ＯＣＨ3 （ＣＨ2 ）4 ）2
をそれぞれ用いた。また有機ビヒクルはエチルセルロー
ス樹脂とテレピネオール等の溶剤を混合したものを用い
た。そして表１〜表３に示す分量のパラジウム分と銀粉
を予め混合し、混合粉とした。有機ビヒクルにその混合
粉末と金属アルコラートを混合し、３本ロールミルにて
混合し組成Ａ〜Ｅの導電性ペーストを得た。The palladium powder shown in Tables 1 to 3 has a particle size of 0.1 to 0.3 μm, and the silver powder has a particle size of 0.2 to 0.5 μm.
Was used. On the other hand, the metal alcoholate has a particle size of 0.2 to
0.5 μm Nb containing 34.8 wt% niobium
(OCH 3 (CH 2 ) 4 ) 2 , Fe (OCH 3 (CH 2 ) 4 ) 3 containing 17.6 wt% of iron, and 5
Ta (OCH 3 (CH 2 ) 4 ) 2 containing 1.0 wt%
Were used. The organic vehicle used was a mixture of ethyl cellulose resin and a solvent such as terpineol. Then, palladium components and silver powder in the amounts shown in Tables 1 to 3 were mixed in advance to obtain a mixed powder. The mixed powder and the metal alcoholate were mixed with an organic vehicle, and mixed with a three-roll mill to obtain conductive pastes having compositions A to E.
【０００８】[0008]
【表１】 [Table 1]
【０００９】[0009]
【表２】 [Table 2]
【００１０】[0010]
【表３】 [Table 3]
【００１１】次に厚さ１０μｍの鉛系の誘電体セラミッ
クのグリーンシート上に所定のパターンで各々の導電性
ペーストを印刷して１４０層積層し、圧着、切断した未
焼成の積層セラミックコンデンサを作製した。未焼成の
積層セラミックコンデンサを３００〜４００℃でバイン
ダを飛ばした後に１００℃／Ｈの速度で昇温し、１００
０℃で２時間保持した後、１００℃／Ｈで降温し積層セ
ラミックコンデンサ素子を得た。Next, 140 layers of each conductive paste are printed in a predetermined pattern on a green sheet of a lead-based dielectric ceramic having a thickness of 10 μm, and 140 layers are laminated, pressed and cut to produce an unfired multilayer ceramic capacitor. did. After the binder is blown off the unfired multilayer ceramic capacitor at 300 to 400 ° C., the temperature is increased at a rate of 100 ° C./H.
After maintaining at 0 ° C. for 2 hours, the temperature was lowered at 100 ° C./H to obtain a multilayer ceramic capacitor element.
【００１２】得られた積層セラミックコンデンサ素子に
ついて１００００個中の剥離、クラックの発生を調べ
た。その結果を表４〜６に示す。表４〜６に示すように
誘電体の構成組成と同一の元素であるＮｂ，Ｆｅ，Ｔａ
のうち少なくとも一つを含む金属アルコラート中のＮ
ｂ，Ｆｅ，Ｔａの含有量が導電性ペースト中の金属粉末
に対して１．５〜１０．０ｗｔ％の範囲で含有される導
電性ペーストを用いることによって効果的に剥離やクラ
ックを抑制できる。With respect to the obtained multilayer ceramic capacitor element, the occurrence of peeling and cracking in 10,000 pieces was examined. The results are shown in Tables 4 to 6. As shown in Tables 4 to 6, Nb, Fe, and Ta, which are the same elements as the constituent composition of the dielectric, are used.
In metal alcoholates containing at least one of the following:
By using a conductive paste containing b, Fe, and Ta in a range of 1.5 to 10.0 wt% with respect to the metal powder in the conductive paste, peeling and cracking can be effectively suppressed.
【００１３】表４〜６及び図１〜３に示すように金属ア
ルコラート中のＮｂ，Ｆｅ，Ｔａの量が金属粉末量の１
０．０ｗｔ％を越えると内部電極の焼結が進まず、また
電極切れが起きたりなどと内部電極の特性を劣化させ、
誘電正接特性に悪影響を与える。なお、金属アルコラー
トの量を増すと導電性ペーストの粘度低下の原因にな
り、作業性を困難にさせるので上記の金属量が効果的で
ある。As shown in Tables 4 to 6 and FIGS. 1 to 3, the amounts of Nb, Fe and Ta in the metal alcoholate are 1% of the amount of the metal powder.
If the content exceeds 0.0 wt%, the sintering of the internal electrode does not proceed, and the characteristics of the internal electrode are degraded, such as electrode breakage,
It has an adverse effect on the dielectric loss tangent characteristic. It should be noted that increasing the amount of the metal alcoholate causes a decrease in the viscosity of the conductive paste and makes the workability difficult, so that the above-mentioned metal amount is effective.
【００１４】[0014]
【表４】 [Table 4]
【００１５】[0015]
【表５】 [Table 5]
【００１６】[0016]
【表６】 [Table 6]
【００１７】[0017]
【発明の効果】以上説明したように本発明は、誘電体の
構成組成と同一の元素であるＮｂ，Ｆｅ，Ｔａのうち少
なくとも一つを含む金属アルコラートを含有させた導電
性ペーストを用いることによって、剥離、クラックなど
の構造欠陥の発生を、防止することができる。As described above, the present invention uses a conductive paste containing a metal alcoholate containing at least one of Nb, Fe, and Ta, which are the same elements as the constituent composition of the dielectric. Occurrence of structural defects such as peeling, cracking and the like can be prevented.
【００１８】誘電体の構成組成の同一の元素であるＮ
ｂ，Ｆｅ，Ｔａのうち少なくとも一つを含む金属アルコ
ラールを含有させた導電性ペーストを乾燥、焼成の工程
時に上記の金属アルコラートが分解し、微細なＮｂ，Ｆ
ｅ，Ｔａとなって金属粉末表面に付着する。このＮｂ，
Ｆｅ，Ｔａは金属の相互拡散を妨げるため焼結収縮を抑
える。N, which is the same element in the composition of the dielectric,
The above-mentioned metal alcoholate is decomposed during the process of drying and firing a conductive paste containing a metal alcohol containing at least one of b, Fe, and Ta, and fine Nb, F
e and Ta are attached to the surface of the metal powder. This Nb,
Fe and Ta suppress sintering shrinkage because they prevent interdiffusion of metals.
【００１９】一般的にセラミックの焼結収縮に比べて金
属粉末の焼結収縮量が大きく、この収縮量の差が剥離、
クラック要因となっているが、誘電体の構成組成と同一
の元素であるＮｂ，Ｆｅ，Ｔａのうち少なくとも一つを
含む金属アルコラートを適量添加することで金属粉末の
焼結収縮量をセラミックの焼結収縮量にあわせることが
でき、剥離、クラックの発生を抑え、また焼結性の阻害
をも抑え電気的特性の劣化が起こらないという効果を得
る。Generally, the amount of sintering shrinkage of a metal powder is larger than that of ceramic, and the difference in the amount of shrinking is caused by peeling,
Although it is a factor of cracking, the amount of sintering shrinkage of the metal powder can be reduced by adding an appropriate amount of a metal alcoholate containing at least one of Nb, Fe, and Ta, which is the same element as the constituent composition of the dielectric. It can be adjusted to the amount of binding shrinkage, and has the effect of suppressing the occurrence of peeling and cracks, suppressing the sinterability, and preventing the electrical characteristics from deteriorating.
【図１】本発明の実施例の導電性ペースト中の金属粉末
に対するＮｂの量と電気特性の関係を示す図である。FIG. 1 is a diagram showing the relationship between the amount of Nb and the electrical characteristics of a metal powder in a conductive paste according to an example of the present invention.
【図２】本発明の実施例の導電性ペースト中の金属粉末
に対するＦｅの量と電気特性の関係を示す図である。FIG. 2 is a diagram showing the relationship between the amount of Fe and the electrical characteristics with respect to metal powder in a conductive paste according to an example of the present invention.
【図３】本発明の実施例の導電性ペースト中の金属粉末
に対するＴａの量と電気特性の関係を示す図である。FIG. 3 is a diagram showing the relationship between the amount of Ta and the electrical properties of metal powder in a conductive paste according to an example of the present invention.
Claims (2)
を混練してなる誘電体セラミックコンデンサ用導電性ペ
ーストにおいて、誘電体の構成組成と同一であるＮｂ，
Ｆｅ，Ｔａのうち少なくとも一つを含む金属アルコラー
トを含有することを特徴とする誘電体セラミックコンデ
ンサ用導電性ペースト。1. A conductive paste for a dielectric ceramic capacitor obtained by kneading a metal powder containing silver, an organic binder and a solvent, wherein Nb,
A conductive paste for a dielectric ceramic capacitor, comprising a metal alcoholate containing at least one of Fe and Ta.
ｂ，Ｆｅ，Ｔａのうち少なくとも一つを含む金属アルコ
ラート中のＮｂ，Ｆｅ，Ｔａの量が、導電性ペースト中
の金属粉末に対して１．５〜１０．０ｗｔ％の範囲で含
有されることを特徴とする請求項１記載の誘電体セラミ
ックコンデンサ用導電性ペースト。2. The compositional composition of a dielectric material is the same element N
The amount of Nb, Fe, Ta in the metal alcoholate containing at least one of b, Fe, and Ta is contained in the range of 1.5 to 10.0 wt% with respect to the metal powder in the conductive paste. The conductive paste for a dielectric ceramic capacitor according to claim 1, wherein
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10374495A JP2735027B2 (en) | 1995-04-27 | 1995-04-27 | Conductive paste for dielectric ceramic capacitors |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10374495A JP2735027B2 (en) | 1995-04-27 | 1995-04-27 | Conductive paste for dielectric ceramic capacitors |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH08298224A JPH08298224A (en) | 1996-11-12 |
| JP2735027B2 true JP2735027B2 (en) | 1998-04-02 |
Family
ID=14362119
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10374495A Expired - Lifetime JP2735027B2 (en) | 1995-04-27 | 1995-04-27 | Conductive paste for dielectric ceramic capacitors |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2735027B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100596288B1 (en) * | 1999-06-30 | 2006-07-03 | 다이요 유덴 가부시키가이샤 | Manufacturing method of laminated ceramic electronic parts |
-
1995
- 1995-04-27 JP JP10374495A patent/JP2735027B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH08298224A (en) | 1996-11-12 |
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