JP2004221183A - Method of manufacturing laminated ceramic electronic component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing laminated ceramic electronic component which is freed from a problem of deviation in the positioning between an internal electrode layer and ceramic layer for controlling generation of stepped portion and from generation structural defect resulting by the stepped position depending on existence or no-existence of internal electrode layer. <P>SOLUTION: The ceramic layer 11 for controlling generation of stepped portion is bonded covering the entire surface including a plurality of internal electrode layers 12 patterned over the ceramic layer 13 and the part where the internal electrode layer 12 is not formed. Thereafter, the ceramic layer 11 for controlling the stepped portion over the internal electrode layer 12 is removed. Accordingly, the ceramic layer 11 for controlling the stepped portion is formed to the part where the internal electrode layer 12 is not formed in order to control generation of the stepped portion depending on existence or non-existence of the internal electrode layer 12. Therefore, since the ceramic layer 11 for controlling the stepped portion is formed like a sheet, a problem of deviation in the positioning can be eliminated and the laminated ceramic electronic component not generating a structural defect resulting from the stepped portion depending on existence and non-existence of internal electrode layer can be obtained easily. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【００４２】
（表１）に示すように、粘着強度Ｂ１を粘着強度Ａ１および粘着強度Ｄ１に比して小さくすることにより、内部電極層１２上の段差抑制用セラミック層１１を剥離する際に、内部電極層１２を剥離することなく、内部電極層１２上にある段差抑制用セラミック層１１のみを容易に除去することが可能となった。本実施の形態１においては、内部電極層１２はセラミック層１３上に内部電極ペーストを印刷乾燥することにより形成したので内部電極層１２とセラミック層１３との界面は強固に粘着しており、粘着強度Ａ１は内部電極層１２とこの上に貼り合わせた粘着テープとの界面の粘着強度よりも大きく、粘着テープが内部電極層１２から先に剥がれたため、測定上限以上となり、セラミック層１３から内部電極層１２が剥離することは無かった。
【００４３】
また、粘着強度Ｂ１は、段差抑制用セラミック層１１のキャリアフィルムからの剥離面と、内部電極層１２の有機バインダ成分が比較的疎となる表面を貼り合わせていることと、内部電極層１２中に含まれる有機バインダ成分のガラス転移点以下の温度１０℃以上３０℃以下、および加圧力０．１ＭＰａ以上１０ＭＰａ以下の条件の低圧力で圧着したので、ほとんど粘着していないため測定限界下限以下となっており、容易に内部電極層１２上にある段差抑制用セラミック層１１を除去することができた。
【００４４】
ここで、粘着強度Ｂ１≧粘着強度Ａ１とすると、内部電極層１２上にある段差抑制用セラミック層１１を除去する際に、内部電極層１２も同時に除去されて、所望の電気特性が得られないので望ましくない。また、粘着強度Ｂ１≧粘着強度Ｄ１とすると、内部電極層１２上の除去するべき段差抑制用セラミック層１１が残ってしまい、内部電極層１２間のセラミック有効層の厚みを変化させ所望の電気特性が得られないので望ましくない。
【００４５】
従って、内部電極層１２上にある段差抑制用セラミック層１１の除去を容易に行うためには、粘着強度Ｂ１は、粘着強度Ａ１および粘着強度Ｄ１に比して小さいことが必要となる。
【００４６】
次に、粘着強度Ｃ１を粘着強度Ｄ１に比して大きくすることにより、内部電極層１２上の段差抑制用セラミック層１１を剥離する際に、隣接する内部電極層１２間にある段差抑制用セラミック層１１が除去されることなく容易に形成することが可能となった。本実施の形態１においては、隣接する内部電極層１２間にあるセラミック層１３と段差抑制用セラミック層１１とは、有機バインダ成分が比較的密であるキャリアフィルムを剥離した面同士を貼り合わせているために、温度１０℃以上３０℃以下、加圧力０．１ＭＰａ以上１０ＭＰａ以下の条件の低圧下での圧着でも十分に粘着し、隣接する内部電極層１２間にあるセラミック層１３と段差抑制用セラミック層１１との間の粘着強度Ｃ１は大きい。また、段差抑制用セラミック層のシート強度Ｅ１を、粘着強度Ｄ１に比して小さくすることにより、内部電極層１２上の段差抑制用セラミック層１１のみを除去して、隣接する内部電極層１２間に段差抑制用セラミック層１１を容易に形成することが可能となった。
【００４７】
ここで、粘着強度Ｄ１≧粘着強度Ｃ１とすると、隣接する内部電極層１２間に残すべき段差抑制用セラミック層１１が粘着層１５に粘着して除去されてしまうので望ましくない。また、シート強度Ｅ１≧粘着強度Ｄ１とすると、内部電極層１２上にある段差抑制用セラミック層１１が粘着層１５から剥れ、段差抑制用セラミック層１１のパターンニングができずに内部電極層１２上に残ってしまい、内部電極層１２間のセラミック有効層の厚みを変化させ所望の電気特性が得られないので望ましくない。従って、段差抑制用セラミック層を精度良く形成するために、シート強度Ｅ１は粘着強度Ｄ１に比して小さいほど望ましい。
【００４８】
以上から、粘着強度Ａ１、Ｂ１、Ｃ１、Ｄ１およびシート強度Ｅ１の大小を利用してセラミック層１３上に形成された複数個の内部電極層１２上に、段差抑制用セラミック層１１を内部電極層１２と内部電極層１２が形成されていない部分の全面を覆うように貼り合わせた後、内部電極層１２上にある段差抑制用セラミック層１１のみを除去して、隣接する内部電極層１２間に段差抑制用セラミック層１１を形成するためには、それぞれの強度の関係が、粘着強度Ａ１＞粘着強度Ｂ１であり、粘着強度Ｄ１＞粘着強度Ｂ１であり、かつ粘着強度Ｃ１＞粘着強度Ｄ１＞シート強度Ｅ１であることが必要であり、これらの強度の大小関係を満たすことにより、内部電極層１２上にある段差抑制用セラミック層１１を除去して、且つ内部電極層１２の無い部分に段差抑制用セラミック層１１を残すことができるので、従来の技術で問題となっていた内部電極層１２と段差抑制用セラミック層１１との重ね合わせによる位置ずれが発生すること無く段差抑制用セラミック層１１を容易にパターンニングすることが可能となる。
【００４９】
次に、図１（ｆ）に示すように、キャリアフィルム上に形成した厚み１０μｍのセラミック層１３を、温度５０℃以上１００℃以下、加圧力５ＭＰａ以上１５ＭＰａ以下の条件で加熱圧着した後、キャリアフィルムを剥離して、有効層となるセラミック層１３を形成した。
【００５０】
次に、上記のセラミック層１３の上に、図１（ａ）から図１（ｆ）に示したと同様な方法で、内部電極層１２の形成、段差抑制用セラミック層１１の形成およびセラミック層１３の形成の工程を繰り返して行い、内部電極層１２と段差抑制用セラミック層１１とを１０１枚、セラミック層１３を１００枚積層して図１（ｇ）に示す状態を得た。
【００５１】
次に、この図１（ｇ）に示す状態の上に、厚み５０μｍのセラミック層１３を積層、加熱圧着した後、キャリアフィルムを剥離する動作を繰り返し行い所定の枚数だけ重ね合わせて上無効層部を形成し、図１（ｈ）に示す積層体グリーンブロックを作製した。
【００５２】
次に、作製された積層体グリーンブロックを、所定の寸法に切断して個片とし積層体グリーンチップを作製した。次に、得られた積層体グリーンチップを所定の雰囲気と温度で脱脂、焼成した後、内部電極層の露出した両端面に外部電極を形成して積層セラミックコンデンサの完成品を得た。
【００５３】
この本実施の形態１の積層セラミックコンデンサは、内部電極層１２と、段差抑制用セラミック層１１とを精度良く、かつ容易に積層することが可能となるので、内部電極層１２の有無による段差を低減し、構造欠陥の発生を抑制することができた。
【００５４】
また、段差抑制用セラミック層１１は、セラミック層１３と同一の組成のものを用いるので、積層体を焼成した際の段差抑制用セラミック層１１とセラミック層１３の焼結収縮挙動が安定するために構造欠陥がさらに発生しにくくなる。
【００５５】
また、本実施の形態１においては、段差抑制用セラミック層１１、セラミック層１３、セラミック層１３および内部電極層１２の厚み方向に生じた有機バインダ成分の分布の疎密を利用することにより、段差抑制用セラミック層１１と内部電極層１２との間の粘着強度Ｂ１や内部電極層１２を形成したセラミック層１３と段差抑制用セラミック層１１との間の粘着強度Ｃ１の大小を制御して、容易に段差抑制用セラミック層１１を形成したが、段差抑制用セラミック層１１、セラミック層１３、セラミック層１３および内部電極層１２に含まれる有機バインダの種類、添加量およびガラス転移点等を変化させることにより、それぞれの界面の粘着強度を制御しても同様の効果が得られる。
【００５６】
なお、本実施の形態１においては、段差抑制用セラミック層１１はその厚みを内部電極層１２と略同一の２μｍとして内部電極層１２と同枚数の段差抑制用セラミック層１１を形成したが、段差抑制用セラミック層１１の厚みや層数に特に制限は無く、内部電極層の総厚みの３０％から１２０％に設定されるのが望ましい。さらに望ましくは５０％から１００％の範囲で決定されるのが望ましい。また、前述した粘着強度Ｂ、Ｃ、Ｄおよびシート強度Ｅを各層に含まれる有機バインダの種類、添加量およびガラス転移点等を適当な範囲で制御することにより、さらに厚みの厚い段差抑制用セラミック層１１を一度に形成して段差抑制用セラミック層の形成回数を削減して生産性を向上させることも可能である。
【００５７】
また、隣接する内部電極層１２間に段差抑制用セラミック層１１の境目を精度良く形成するために、あらかじめ段差抑制用セラミック層１１を内部電極層１２と内部電極層の無い部分の全体を覆うように貼り合わせた後に、弾性ゴム等により全体を均一に加圧圧着して、段差抑制用セラミック層１１を内部電極層１２の外周部のセラミック層１３にムラ無く粘着させることが望ましい。
【００５８】
（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に記載の発明について説明する。
【００５９】
本発明の実施の形態２について図面を参照して説明する。図２は本実施の形態２における積層体グリーンブロックの製造工程を説明するための断面図である。図２において、１１は段差抑制用セラミック層、１３はセラミック層、１４はベースフィルム、１５は粘着層、２２は内部電極層、２６は支持フィルムである。
【００６０】
以下、本実施の形態２における積層セラミックコンデンサの製造方法について説明する。ここで、ベースフィルム１４および粘着層１５は実施の形態１と同様のものを用い、段差抑制用セラミック層１１、セラミック層１３は実施の形態１と同様にして作製したものを用いたので、これらは、同番号を付し詳細は省略する。また、内部電極層２２の形成に用いた内部電極ペーストも、実施の形態１と同様のものを用いたので、詳細な説明は省略する。
【００６１】
まず、図２（ａ）に示すように、支持体となる支持フィルム２６上に、本実施の形態１で使用した内部電極ペーストを所定のパターンでスクリーン印刷後、乾燥して厚み２μｍの内部電極層２２を複数個形成した。
【００６２】
次に、図２（ｂ）に示すように、支持フィルム２６上に形成された複数個の内部電極層２２上に、キャリアフィルム上に形成した厚み２μｍの段差抑制用セラミック層１１をキャリアフィルムから剥離して、剥離した面が下になるように内部電極層２２と内部電極層２２が形成されていない部分を覆うように貼り合わせた。
【００６３】
次に、図２（ｃ）に示すように、貼り合わされた段差抑制用セラミック層１１の上に、ベースフィルム１４上に形成した厚み５０μｍのアクリル樹脂系の粘着層１５を、温度１０℃以上３０℃以下、加圧力０．１ＭＰａ以上１０ＭＰａ以下の条件で圧着した。
【００６４】
次に、図２（ｄ）に示すように、ベースフィルム１４および粘着層１５を剥離するとともに、内部電極層２２上にある段差抑制用セラミック層１１を粘着層１５に粘着させて除去して、隣接する内部電極層２２間に段差抑制用セラミック層１１を残すことにより、内部電極層２２と段差抑制用セラミック層１１とからなる段差の抑制された複合層を支持フィルム２６上に形成し、図２（ｅ）に示す状態を得た。これを複数枚作製した。
【００６５】
ここで、内部電極層２２と支持フィルム２６との間の粘着強度を粘着強度Ａ２、内部電極層２２と段差抑制用セラミック層１１との間の粘着強度を粘着強度Ｂ２、段差抑制用セラミック層１１と支持フィルム２６との間の粘着強度を粘着強度Ｃ２、段差抑制用セラミック層１１と粘着層１５との間の粘着強度を粘着強度Ｄ２、段差抑制用セラミック層１１のシート強度をシート強度Ｅ２として、本実施の形態２における各層間の粘着強度および段差抑制用セラミック層のシート強度Ｅ２を実施の形態１と同様にして測定した結果を（表２）に示す。
【００６６】
【表２】

【００６７】
（表２）に示すように、それぞれの強度の関係を、粘着強度Ａ２＞粘着強度Ｂ２であり、粘着強度Ｄ２＞粘着強度Ｂ２であり、かつ粘着強度Ｃ２＞粘着強度Ｄ２＞シート強度Ｅ２となるようにした。これにより、本実施の形態２においては内部電極層２２上にある段差抑制用セラミック層１１を除去して、内部電極層２２の無い部分に段差抑制用セラミック層１１を残すことができるので、従来の技術で問題となっていた位置ずれの問題が発生すること無く、内部電極層２２間に段差抑制用セラミック層１１を容易にパターンニングすることができた。
【００６８】
一方、実施の形態１と同様に、キャリアフィルム上に形成した厚み５０μｍのセラミック層１３を、キャリアフィルム側から温度５０℃以上１００℃以下、加圧力５ＭＰａ以上１５ＭＰａ以下の条件で加熱圧着して台座面（図示せず）に貼り合わせた後、キャリアフィルムを剥離するという動作を繰り返し行って、所定の枚数となるようにセラミック層１３を積み重ねて下無効層部となるセラミック層１３を作製した。
【００６９】
そして、下無効層部のセラミック層１３上に、図２（ｅ）の支持フィルム２６上に形成された複合層を、支持フィルム２６側から温度５０℃以上１００℃以下、加圧力５ＭＰａ以上１５ＭＰａ以下の条件で加熱圧着した後、図２（ｆ）に示すように、支持フィルム２６を剥離した。
【００７０】
次に、下無効層部のセラミック層１３上に形成された内部電極層２２と段差抑制用セラミック層１１とからなる複合層上に、キャリアフィルム上に形成された厚み１０μｍのセラミック層１３をキャリアフィルム側から温度５０℃以上１００℃以下、加圧力５ＭＰａ以上１５ＭＰａ以下の条件で加熱圧着した後、キャリアフィルムを剥離し、図２（ｇ）に示す状態を得た。
【００７１】
続いて、上記で説明した図２（ｆ）および図２（ｇ）の工程を繰り返して行い、内部電極層２２と段差抑制用セラミック層１１とを１０１枚、セラミック層１３を１００枚積層して図２（ｈ）に示す状態を得た。
【００７２】
次に、この図２（ｈ）に示す状態の上に、厚み５０μｍのセラミック層１３を積層、加熱圧着した後、キャリアフィルムを剥離する動作を繰り返し行い所定の枚数だけ重ね合わせて上無効層部を形成し、図２（ｉ）に示す積層体グリーンブロックを作製した。
【００７３】
次に、実施の形態１と同様に、作製された図２（ｉ）に示す積層体グリーンブロックを、所定の寸法に切断して個片とし積層体グリーンチップを作製した。次に、得られた積層体グリーンチップを所定の雰囲気と温度で脱脂、焼成した後、内部電極層の露出した両端面に外部電極を形成して積層セラミックコンデンサの完成品を得た。
【００７４】
本実施の形態２の積層セラミックコンデンサもまた、内部電極層２２と段差抑制用セラミック層１１とを精度良く、かつ容易に積層することが可能となるので、内部電極層２２の有無による段差を低減し、構造欠陥の発生を抑制することができた。
【００７５】
なお、本実施の形態２は、支持フィルム２６上に形成された内部電極層２２と段差抑制用セラミック層１１とからなる段差の抑制された複合層をあらかじめ作製し、この複合層とセラミック層１３とを交互に積層するので、実施の形態１の内部電極層２２と段差抑制用セラミック層１１をそれぞれ別々に積層する場合と比較して、積層体グリーンブロックの作製に要する時間を短縮することができ、生産性の向上が図れる。
【００７６】
（実施の形態３）
以下、実施の形態３を用いて、本発明の特に請求項３に記載の発明について説明する。
【００７７】
本発明の実施の形態３について図面を参照して説明する。図３は本実施の形態３における積層体グリーンブロックの製造工程を説明するための断面図である。図３において、１１は段差抑制用セラミック層、１３はセラミック層、１４はベースフィルム、１５は粘着層、２２は内部電極層、２６は支持フィルムである。これらはいずれも、実施の形態２と同様のものを用いたので、同番号を付し詳細は省略する。
【００７８】
以下、本実施の形態３における積層セラミックコンデンサの製造方法について説明する。なお、図３（ａ）から図３（ｅ）までの工程は、実施の形態２の図２（ａ）から図２（ｅ）までの工程と同様なので説明は省略する。
【００７９】
図３（ｅ）に示すように、内部電極層２２と段差抑制用セラミック層１１とからなる複合層を支持フィルム２６上に形成した後、図３（ｅ）の複合層の上に、キャリアフィルム上に形成された厚み１０μｍのセラミック層１３をキャリアフィルムから剥離して、剥離した面を下にして、温度１０℃以上１００℃以下、圧力０．１ＭＰａ以上１５ＭＰａ以下の条件で貼り合わせて、内部電極層２２が埋め込まれ、内部電極層２２の有無による段差を抑制した図３（ｆ）に示す複合シートを支持フィルム２６上に形成した。これを複数枚作製した。
【００８０】
なお、各層の界面の粘着強度および段差抑制用セラミック層１１のシート強度は、いずれも、上述した本実施の形態２と同様であり（表２）に示したとおりである。
【００８１】
一方、実施の形態１と同様に、キャリアフィルム上に形成した厚み５０μｍのセラミック層１３を、キャリアフィルム側から温度５０℃以上１００℃以下、加圧力５ＭＰａ以上１５ＭＰａ以下の条件で加熱圧着して台座面（図示せず）に貼り合わせた後、キャリアフィルムを剥離するという動作を繰り返し行って、所定の枚数となるようにセラミック層１３を積み重ねて下無効層部となるセラミック層１３を作製した。
【００８２】
次に、上記の下無効層部となるセラミック層１３の上に、図３（ｆ）の支持フィルム２６上に形成された複合シートを、支持フィルム２６側から温度５０℃以上１００℃以下、加圧力５ＭＰａ以上１５ＭＰａ以下の条件で加熱圧着した後、図３（ｇ）に示すように、支持フィルム２６を剥離した。
【００８３】
続いて、上記で説明した、図３（ｆ）の支持フィルム２６上に形成された複合シートを加熱圧着する図３（ｇ）の工程を繰り返して行い、内部電極層２２と段差抑制用セラミック層１１とを１０１枚、セラミック層１３を１００枚積層して図３（ｈ）に示す状態を得た。
【００８４】
次に、この図３（ｈ）に示す状態の上に、厚み５０μｍのセラミック層１３を積層、加熱圧着した後、キャリアフィルムを剥離する動作を繰り返し行い所定の枚数だけ重ね合わせて上無効層部を形成し、図３（ｉ）に示す積層体グリーンブロックを作製した。
【００８５】
次に、実施の形態１と同様に、作製された図３（ｉ）に示す積層体グリーンブロックを、所定の寸法に切断して個片とし積層体グリーンチップを作製した。次に、得られた積層体グリーンチップを所定の雰囲気と温度で脱脂、焼成した後、内部電極層の露出した両端面に外部電極を形成して積層セラミックコンデンサの完成品を得た。
【００８６】
この実施の形態３の積層セラミックコンデンサもまた、内部電極層２２と段差抑制用セラミック層１１とを精度良く、かつ容易に積層することが可能となるので、内部電極層２２の有無による段差を低減し、構造欠陥の発生を抑制することができた。
【００８７】
なお、本実施の形態３は、支持フィルム２６上に形成された内部電極層２２と段差抑制用セラミック層１１とからなる複合層とこの上にセラミック層１３を貼り合わせた複合シートをあらかじめ作製し、この複合シートを積層するので、実施の形態２と比較しても、積層体グリーンブロックの作製に要する時間を短縮することができ、生産性の向上が図れる。
【００８８】
（実施の形態４）
以下、実施の形態４を用いて、本発明の特に請求項４および請求項５に記載の発明について説明する。
【００８９】
本発明の実施の形態４について図面を参照して説明する。図４は本実施の形態４における積層体グリーンブロックの製造工程を説明するための断面図である。図４において、１１は段差抑制用セラミック層、１３はセラミック層、１４はベースフィルム、１５は粘着層、４２は内部電極層、４６は支持フィルム、４７は紫外線硬化樹脂を含有する粘着層である。
【００９０】
以下、本実施の形態４における積層セラミックコンデンサの製造方法について説明する。ここで、ベースフィルム１４および粘着層１５は実施の形態１と同様のものを用い、段差抑制用セラミック層１１、セラミック層１３は実施の形態１と同様にして作製したものを用いたので、これらは、同番号を付し詳細は省略する。また、内部電極層４２の形成に用いた内部電極ペーストも、実施の形態１と同様のものを用いたので、詳細な説明は省略する。
【００９１】
まず、支持体となる支持フィルム４６上に形成された紫外線硬化樹脂を含有する粘着層４７上に、キャリアフィルム上に形成された厚み１０μｍのセラミック層１３を貼り合わせ、キャリアフィルムを剥離した。次に、セラミック層１３の上に、実施の形態１と同様にして厚み２μｍの内部電極層４２を複数個形成し、図４（ａ）に示す状態を得た。
【００９２】
紫外線硬化樹脂を含有する粘着層４７としては、セラミック層１３との粘着強度が、実施の形態１と同様な方法で測定して、紫外線を照射する前には１０Ｎ／ｃｍ以上の測定限界上限以上であり、紫外線照射して硬化後には０．５Ｎ／ｃｍ以下となるものを用いた。
【００９３】
次に、複数個の内部電極層４２を形成したセラミック層１３上に、内部電極層４２と内部電極層４２が形成されていない部分のセラミック層１３を覆うように、キャリアフィルム上に形成された厚み２μｍの段差抑制用セラミック層１１をキャリアフィルムから剥離して、剥離した面が下になるようにして、図４（ｂ）に示すように貼り合わせた。そして、温度１０℃以上３０℃以下、加圧力０．１ＭＰａ以上１０ＭＰａ以下の条件で圧着した。
【００９４】
次に、貼り合わされた段差抑制用セラミック層１１の上に、図４（ｃ）に示すように、ベースフィルム１４上に形成した厚み５０μｍのアクリル樹脂系粘着層１５を貼り合わせた後、温度１０℃以上３０℃以下、加圧力０．１ＭＰａ以上１０ＭＰａ以下の条件で圧着した。
【００９５】
次に、図４（ｄ）に示すように、ベースフィルム１４および粘着層１５を剥離するとともに、内部電極層４２上にある段差抑制用セラミック層１１を粘着層１５に粘着させて除去し、粘着層４７を介して支持フィルム４６上に形成されたセラミック層１３の上に内部電極層４２と段差抑制用セラミック層１１とを形成し、図４（ｅ）に示す複合シートを複数枚作製した。
【００９６】
ここで、内部電極層４２とセラミック層１３との間の粘着強度を粘着強度Ａ４、内部電極層４２と段差抑制用セラミック層１１との間の粘着強度を粘着強度Ｂ４、段差抑制用セラミック層１１とセラミック層１３との間の粘着強度を粘着強度Ｃ４、段差抑制用セラミック層１１と粘着層１５との間の粘着強度を粘着強度Ｄ４、段差抑制用セラミック層１１のシート強度をシート強度Ｅ４として、本実施の形態４における各層の粘着強度および段差抑制用セラミック層のシート強度Ｅ４を上述した実施の形態１と同様にして測定した結果を（表３）に示す。
【００９７】
【表３】

【００９８】
（表３）に示すように、それぞれの強度の関係を、粘着強度Ａ４＞粘着強度Ｂ４であり、粘着強度Ｄ４＞粘着強度Ｂ４であり、かつ粘着強度Ｃ４＞粘着強度Ｄ４＞シート強度Ｅ４となるようにした。これにより、本実施の形態４においても、内部電極層４２上にある段差抑制用セラミック層１１を除去して、内部電極層４２の無い部分にセラミック層１３上に段差抑制用セラミック層１１を残すことができるので、従来の技術で問題となっていた位置ずれの問題が発生すること無く、内部電極層４２間に段差抑制用セラミック層１１を容易にパターンニングすることができた。
【００９９】
また、上記の複合シートを作製する工程において、セラミック層１３は、紫外線硬化樹脂を含有する粘着層４７により十分な粘着強度で支持フィルム４６上に保持され、安定して複合シートを作製することができた。
【０１００】
一方、実施の形態１と同様に、キャリアフィルム上に形成した厚み５０μｍのセラミック層１３を、キャリアフィルム側から温度５０℃以上１００℃以下、加圧力５ＭＰａ以上１５ＭＰａ以下の条件で加熱圧着して台座面（図示せず）に貼り合わせた後、キャリアフィルムを剥離するという動作を繰り返し行って、所定の枚数となるようにセラミック層１３を積み重ねて下無効層部となるセラミック層１３を作製した。
【０１０１】
次に、上記の下無効層部となるセラミック層１３の上に、図４（ｅ）の粘着層４７を介して支持フィルム４６上に形成された複合シートを、支持フィルム４６側から温度５０℃以上１００℃以下、加圧力５ＭＰａ以上１５ＭＰａ以下の条件で加熱圧着した。その後、支持フィルム４６側から紫外線を照射することにより粘着層４７を硬化させた後、図４（ｆ）に示すように、粘着層４７とともに支持フィルム４６を剥離した。この際、紫外線の照射により粘着層４７とセラミック層１３との粘着強度は極めて小さくなり、支持フィルム４６および粘着層４７は容易に剥離できた。
【０１０２】
続いて、上記で説明した、図４（ｅ）の粘着層４７を介して支持フィルム４６上に形成された複合シートを加熱圧着する図４（ｆ）の工程を繰り返して行い、内部電極層４２と段差抑制用セラミック層１１とを１０１枚、セラミック層１３を１００枚積層して図４（ｇ）に示す状態を得た。
【０１０３】
次に、この図４（ｇ）に示す状態の上に、厚み５０μｍのセラミック層１３を積層、加熱圧着した後、キャリアフィルムを剥離する動作を繰り返し行い所定の枚数だけ重ね合わせて上無効層部を形成し、図４（ｈ）に示す積層体グリーンブロックを作製した。
【０１０４】
次に、実施の形態１と同様に、作製された図４（ｈ）に示す積層体グリーンブロックを、所定の寸法に切断して個片とし積層体グリーンチップを作製した。次に、得られた積層体グリーンチップを所定の雰囲気と温度で脱脂、焼成した後、内部電極層の露出した両端面に外部電極を形成して、本実施の形態４における積層セラミックコンデンサの完成品を得た。
【０１０５】
本実施の形態４の積層セラミックコンデンサもまた、内部電極層４２と段差抑制用セラミック層１１とを精度良く形成し、かつ容易に積層することが可能となるので、内部電極層４２の有無による段差を低減し、構造欠陥の発生を抑制することができた。
【０１０６】
なお、本実施の形態４も、複合シートをあらかじめ作製し、この複合シートを積層するので、実施の形態３と同様に、積層体グリーンブロックの作製に要する時間を短縮することができ、生産性の向上が図れた。
【０１０７】
（実施の形態５）
以下、実施の形態５を用いて、本発明の特に請求項６に記載の発明について説明する。
【０１０８】
本発明の実施の形態５について図面を参照して説明する。図５は本実施の形態５における積層体グリーンブロックの製造工程を説明するための断面図である。図５において、１１は段差抑制用セラミック層、１３はセラミック層、１４はベースフィルム、１５は粘着層、４６は支持フィルム、４７は紫外線硬化樹脂を含有する粘着層である。これらはいずれも、実施の形態４と同様のものを用いたので、同番号を付し詳細は省略する。５２は内部電極層である。
【０１０９】
以下、本実施の形態５における積層セラミックコンデンサの製造方法について説明する。
【０１１０】
まず、ベースフィルム１４に形成したアクリル樹脂系粘着層１５上に、キャリアフィルムに形成した厚み２μｍの段差抑制用セラミック層１１を、段差抑制用セラミック層１１とアクリル樹脂系粘着層１５を向かい合わせにして貼り合わせた後、段差抑制用セラミック層１１側のキャリアフィルムを剥離して、図５（ａ）に示す状態を得た。
【０１１１】
一方、支持体となる支持フィルム４６上に形成された紫外線硬化樹脂を含有する粘着層４７上に、厚み２μｍの内部電極層５２を複数個形成し、図５（ｂ）に示す状態を得た。紫外線硬化樹脂を含有する粘着層４７と内部電極層５２との粘着強度は、紫外線を照射する前には１０Ｎ／ｃｍ以上の測定限界上限以上であり、紫外線照射後には０．５Ｎ／ｃｍとなるものを用いた。
【０１１２】
次に、図５（ｂ）の内部電極層５２側と、図５（ａ）の段差抑制用セラミック層１１側とを貼り合わせ、温度１０℃以上３０℃以下、加圧力０．１ＭＰａ以上１０ＭＰａ以下の条件で圧着し、図５（ｃ）に示す状態を得た。
【０１１３】
次に、図５（ｄ）に示すように、ベースフィルム１４および粘着層１５を剥離するとともに、内部電極層５２上にある段差抑制用セラミック層１１を粘着層１５に粘着させて除去して、隣接する内部電極層５２間に段差抑制用セラミック層１１を残すことにより、内部電極層５２と段差抑制用セラミック層１１とからなる段差の抑制された複合層を粘着層４７を介して支持フィルム４６上に形成し、図５（ｅ）に示す状態を得た。これを複数枚作製した。
【０１１４】
ここで、内部電極層５２と粘着層４７との間の粘着強度を粘着強度Ａ５、内部電極層５２と段差抑制用セラミック層１１との間の粘着強度を粘着強度Ｂ５、段差抑制用セラミック層１１と粘着層４７との間の粘着強度を粘着強度Ｃ５、段差抑制用セラミック層１１と粘着層１５との間の粘着強度を粘着強度Ｄ５、段差抑制用セラミック層１１のシート強度をシート強度Ｅ５として、本実施の形態５における各層の粘着強度および段差抑制用セラミック層のシート強度Ｅ５を上述した実施の形態１と同様にして測定した結果を（表４）に示す。
【０１１５】
【表４】

【０１１６】
（表４）に示すように、それぞれの強度の関係を、粘着強度Ａ５＞粘着強度Ｂ５であり、粘着強度Ｄ５＞粘着強度Ｂ５であり、かつ粘着強度Ｃ５＞粘着強度Ｄ５＞シート強度Ｅ５となるようにした。これにより、本実施の形態５においても、内部電極層５２上にある段差抑制用セラミック層１１を除去して、内部電極層５２の無い部分に段差抑制用セラミック層１１を残すことができるので、従来の技術で問題となっていた位置ずれの問題が発生すること無く、内部電極層５２間に段差抑制用セラミック層１１を容易に精度良くパターンニングすることができた。
【０１１７】
次に、図５（ｅ）の複合層の上に、キャリアフィルム上に形成された厚み１０μｍのセラミック層１３をキャリアフィルムから剥離して、剥離した面を下にして、温度１０℃以上１００℃以下、圧力０．１ＭＰａ以上１５ＭＰａ以下の条件で貼り合わせて、内部電極層５２が埋め込まれ、内部電極層５２の有無による段差を抑制した図５（ｆ）に示す複合シートを粘着層４７を介して支持フィルム４６上に形成した。これを複数枚作製した。
【０１１８】
一方、実施の形態１と同様に、キャリアフィルム上に形成した厚み５０μｍのセラミック層１３を、キャリアフィルム側から温度５０℃以上１００℃以下、加圧力５ＭＰａ以上１５ＭＰａ以下の条件で加熱圧着して台座面（図示せず）に貼り合わせた後、キャリアフィルムを剥離するという動作を繰り返し行って、所定の枚数となるようにセラミック層１３を積み重ねて下無効層部となるセラミック層１３を作製した。
【０１１９】
次に、上記の下無効層部となるセラミック層１３の上に、図５（ｆ）の粘着層４７を介して支持フィルム４６上に形成された複合シートを、支持フィルム４６側から温度５０℃以上１００℃以下、加圧力５ＭＰａ以上１５ＭＰａ以下の条件で加熱圧着した。その後、支持フィルム４６側から紫外線を照射することにより粘着層４７を硬化させた後、図５（ｇ）に示すように、粘着層４７とともに支持フィルム４６を剥離した。
【０１２０】
続いて、上記で説明した、図５（ｆ）の粘着層４７を介して支持フィルム４６上に形成された複合シートを加熱圧着する図５（ｇ）の工程を繰り返して行い、内部電極層５２と段差抑制用セラミック層１１とを１０１枚、セラミック層１３を１００枚積層して図５（ｈ）に示す状態を得た。
【０１２１】
次に、この図５（ｈ）に示す状態の上に、厚み５０μｍのセラミック層１３を積層、加熱圧着した後、キャリアフィルムを剥離する動作を繰り返し行い所定の枚数だけ重ね合わせて上無効層部を形成し、図５（ｉ）に示す積層体グリーンブロックを作製した。
【０１２２】
次に、実施の形態１と同様に、作製された図５（ｉ）に示す積層体グリーンブロックを所定の寸法に切断して個片とし、積層体グリーンチップを作製した。次に、得られた積層体グリーンチップを所定の雰囲気と温度で脱脂、焼成した後、内部電極層の露出した両端面に外部電極を形成して、本実施の形態５における積層セラミックコンデンサの完成品を得た。
【０１２３】
本実施の形態５の積層セラミックコンデンサもまた、内部電極層５２と段差抑制用セラミック層１１とを精度良く、かつ容易に積層することが可能となるので、内部電極層５２の有無による段差を低減し、構造欠陥の発生を抑制することができた。
【０１２４】
なお、本実施の形態５も、複合シートをあらかじめ作製し、この複合シートを積層するので、実施の形態３および実施の形態４と同様に、積層体グリーンブロックの作製に要する時間を短縮することができ、生産性の向上が図れた。
【０１２５】
以上説明した、本発明の実施の形態１から実施の形態５において得られた積層セラミックコンデンサについて、空洞やデラミネーションなどの内部構造における構造欠陥の発生数、静電容量の不良数をそれぞれ１００個について確認した。静電容量は設計値から±５％以上ずれたものを不良とした。その結果、本発明の実施の形態１から実施の形態５のいずれにおいても不良数はゼロであった。
【０１２６】
比較のために、図６で説明した従来の製造方法により得られた積層セラミックコンデンサについても、同様の評価を行った結果、内部構造欠陥は１３／１００個、静電容量不良は６／１００個発生していた。
【０１２７】
以上から、上記各実施の形態において作製された積層セラミックコンデンサは、構造欠陥の発生、静電容量不良の点において、従来方法よりも改善されていることが確認できた。
【０１２８】
なお、上記各実施の形態において、段差抑制用セラミック層は、内部電極層と同数同位置に配置したが、段差抑制用セラミック層の枚数や積層時の配置位置に制限は無く、内部電極層の有無による段差のトータル段差を考慮して厚みを大きくして枚数を少なくしても、等間隔またはランダムに積層してもよい。
【０１２９】
そして、段差抑制用セラミック層は、その合計厚みが内部電極層の合計厚みと等しくすることが最適である。
【０１３０】
また、上記各実施の形態においては、積層セラミックコンデンサを例に説明したが、セラミック層と内部電極層とを積層した積層セラミック部品においても同様の効果が得られる。
【０１３１】
【発明の効果】
以上のように本発明は、セラミック層と内部電極層とを交互に積層して積層セラミック電子部品の積層体グリーンブロックを作製する工程において、同一面上にパターンニングされた複数個の内部電極層と内部電極層が形成されていない部分とを含む全面を覆うように段差抑制用セラミック層を貼り合わせた後、前記内部電極層上にある前記段差抑制用セラミック層を除去することにより、内部電極層の形成されていない部分に段差抑制用セラミック層を形成して内部電極層の有無による段差を抑制する工程を備えた積層セラミック電子部品の製造方法であり、内部電極層の有無による段差に起因する構造欠陥の発生を抑制し、優れた電気特性を有する積層セラミック部品を、容易に生産性良く得ることができるという効果を奏するものである。
【図面の簡単な説明】
【図１】本発明の実施の形態１における積層体グリーンブロックの製造工程を説明するための断面図
【図２】本発明の実施の形態２における積層体グリーンブロックの製造工程を説明するための断面図
【図３】本発明の実施の形態３における積層体グリーンブロックの製造工程を説明するための断面図
【図４】本発明の実施の形態４における積層体グリーンブロックの製造工程を説明するための断面図
【図５】本発明の実施の形態５における積層体グリーンブロックの製造工程を説明するための断面図
【図６】従来の積層体グリーンブロックの製造工程を説明するための断面図
【符号の説明】
１１ 段差抑制用セラミック層
１２、２２、４２、５２ 内部電極層
１３ セラミック層
１４ ベースフィルム
１５ 粘着層
２６、４６ 支持フィルム
４７ 紫外線硬化樹脂を含有する粘着層[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for manufacturing a multilayer ceramic electronic component.
[0002]
[Prior art]
In recent years, as electronic devices have become smaller and lighter, including electronic devices related to information mobile communication such as mobile phones and computers, multilayer ceramic capacitors, one of the multilayer ceramic electronic components, have also become smaller and larger in capacity. Is strongly desired.
[0003]
In order to increase the capacity of the multilayer ceramic capacitor, the ceramic layers and the internal electrode layers have been made thinner and more highly laminated. However, the thickness difference between the part where the internal electrode layer is formed and the part where the internal electrode layer is not formed, that is, the step due to the presence or absence of the internal electrode layer increases with the increase in the lamination, and the ceramic due to this step is increased. There is a problem that the adhesiveness of the layer is reduced and the delamination of the sintered body element is apt to occur. For this purpose, various methods have been proposed for eliminating steps due to the presence or absence of the internal electrode layer.
[0004]
For example, heretofore, a method for manufacturing a multilayer ceramic electronic component as described above has been proposed. FIG. 6 is a cross-sectional view illustrating a conventional method for manufacturing a multilayer ceramic electronic component.
[0005]
First, as shown in FIG. 6A, a plurality of internal electrode layers 112 are formed on the carrier film 116 by screen printing and drying an internal electrode paste in a predetermined pattern.
[0006]
Next, as shown in FIG. 6B, screen printing is performed using a pattern opposite to that of the internal electrode layer 112 to form a step-reducing ceramic layer 111 on a portion other than the internal electrode layer 112 on the carrier film 116. Then, a first portion shown in FIG. 6C is prepared.
[0007]
On the other hand, a ceramic slurry is applied to almost the entire surface of another carrier film 216 by a doctor blade method or the like and dried to prepare a ceramic sheet 113, and a second portion shown in FIG. 6D is prepared.
[0008]
Then, as shown in FIG. 6E, the second part shown in FIG. 6D and the first part shown in FIG. Then, a multilayer green block of the multilayer ceramic capacitor shown in FIG.
[0009]
As prior art document information related to a method of eliminating a step for forming a step-reducing ceramic layer having a reverse pattern of an internal electrode layer as described above, for example, Patent Document 1, Patent Document 2 and Patent Document 3 are disclosed. Are known.
[0010]
[Patent Document 1]
JP-A-1-208824
[Patent Document 2]
JP-A-2-100306
[Patent Document 3]
JP-A-6-96991
[0011]
[Problems to be solved by the invention]
However, in the above-described conventional method of eliminating a step in which a ceramic layer for suppressing a step is formed in a reverse pattern of the internal electrode layer, it is difficult to align the internal electrode layer and the ceramic layer for suppressing a step, resulting in misalignment. There is a problem that it is easy to occur.
[0012]
Specifically, the pattern for forming the internal electrode layer and the pattern for forming the step-reducing ceramic layer are formed from different patterns. For example, when these are formed by a screen printing method or a gravure printing method, separate screen plates or gravure plates are used for the internal electrode layer and the step-reducing ceramic layer. Therefore, in the current plate making technology, a dimensional difference between the internal electrode layer and the ceramic layer for suppressing a level difference is not small when plate making is performed. In addition, even when forming an internal electrode layer or a step-reducing ceramic layer on a support such as a carrier film by these printing methods, a dimensional difference caused by expansion and contraction of the support itself such as a carrier film is further added. Become. In addition, when the internal electrode layer and the ceramic layer for suppressing a level difference are overlapped by a printing machine or a laminating machine, a dimensional difference occurs due to mechanical alignment.
[0013]
If the position of the superposition of the internal electrode layer and the step-reducing ceramic layer is shifted, a gap is formed between the internal electrode layer and the step-reducing ceramic layer, causing a problem that a cavity is generated in the sintered body element. . In addition, when the step suppressing ceramic layer rides on the internal electrode layer, the thickness of the ceramic layer changes, so that a multilayer ceramic capacitor having a desired capacitance cannot be obtained. .
[0014]
In addition, since the thickness and dimensions of the ceramic layer for forming a predetermined pattern in a wet pattern using a ceramic slurry and a paste are changed due to the surface tension and drying shrinkage of the paste, the ceramic layer for forming a step and having a uniform thickness is small. Has a problem that it is difficult to fabricate it.
[0015]
SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems, and there is no problem of misalignment between the internal electrode layer and the ceramic layer for suppressing a level difference, and there is no problem of a position difference due to the presence or absence of the internal electrode layer even when thinning and high lamination. It is an object of the present invention to provide a method for manufacturing a multilayer ceramic electronic component having excellent electrical characteristics without occurrence of structural defects caused by the above.
[0016]
[Means for Solving the Problems]
In order to achieve the above object, the present invention has the following configuration.
[0017]
According to a first aspect of the present invention, in the step of alternately stacking ceramic layers and internal electrode layers to form a multilayer green block of a multilayer ceramic electronic component, a plurality of patterned green blocks are formed on the same surface. After bonding the step suppressing ceramic layer so as to cover the entire surface including the internal electrode layer and the portion where the internal electrode layer is not formed, removing the step suppressing ceramic layer on the internal electrode layer A step of forming a step-reducing ceramic layer in a portion where the internal electrode layer is not formed to suppress the step due to the presence or absence of the internal electrode layer, thereby producing a multilayer ceramic electronic component. The ceramic layer is not a specific pattern for the internal electrode layer but a sheet shape. Can be positioned very easily without any special requirement, and by removing the ceramic layer for suppressing the step on the internal electrode layer, a ceramic layer for suppressing the step can be selectively formed in the portion where the internal electrode layer is not formed. Therefore, the problem of alignment and displacement between the internal electrode layer and the step-reducing ceramic layer, which has been a problem in the prior art, does not occur.
[0018]
In addition, since the step-reducing ceramic layer has the same sheet shape as the surrounding ceramic layer, it can be formed to be thin and uniform between the internal electrode layers, and can be formed when the laminate is fired. In addition, since the sintering shrinkage behavior of the ceramic layer is stable, structural defects are less likely to occur.
[0019]
The invention according to claim 2 of the present invention particularly forms a plurality of internal electrode layers on a support, and covers the entire surface including the internal electrode layers and a portion where the internal electrode layers are not formed. After bonding the step-reducing ceramic layer to the above, by removing the step-reducing ceramic layer on the internal electrode layer, a composite layer composed of the internal electrode layer and the step-reducing ceramic layer on the support. A method of manufacturing a laminated ceramic electronic component comprising a step of forming and alternately laminating the composite layer and the ceramic layer, whereby the internal electrode layer and the step suppressing ceramic layer are formed on a support in advance. Since the composite layer is formed and the composite layer is laminated at one time, the time required for producing the laminate can be reduced as compared with the case where the internal electrode layer and the step-reducing ceramic layer are separately laminated. It can be, thereby improving the productivity.
[0020]
The invention according to claim 3 of the present invention particularly includes a laminating step of laminating a ceramic layer on a composite layer formed on a support to form a composite sheet, and laminating the composite sheet. This is a method for manufacturing ceramic electronic components, which allows the composite sheets prepared in advance to be laminated at one time, so that the composite layer composed of the internal electrode layer and the ceramic layer for suppressing the level difference and the ceramic layer are separately laminated. As compared with the case of performing the method, the time required for manufacturing the laminate can be further reduced, and the productivity can be improved.
[0021]
In the invention according to claim 4 of the present invention, in particular, a ceramic layer is formed on a support, a plurality of internal electrode layers are formed on the ceramic layer, and the internal electrode layer and the internal electrode layer are formed. After bonding the step-reducing ceramic layer so as to cover the entire surface including the unprocessed portion, by removing the step-reducing ceramic layer on the internal electrode layer, on the ceramic layer on the support This is a method for manufacturing a multilayer ceramic electronic component, comprising the steps of: preparing a composite sheet having a composite layer formed of an internal electrode layer and a step-reducing ceramic layer, and laminating the composite sheet. Since the composite sheet prepared in advance can be laminated at a time, the composite layer composed of the internal electrode layer and the step-reducing ceramic layer and the ceramic layer are separately laminated. Compared to case, it can be further shortened, thereby improving the productivity of time required for production of the laminate.
[0022]
In the invention according to claim 5 of the present invention, in particular, a ceramic layer is formed on a support via an adhesive layer containing an ultraviolet curable resin, and an internal electrode layer and a ceramic layer for suppressing a step are formed on the ceramic layer. A method for producing a laminated ceramic electronic component, comprising the steps of: producing a composite sheet having a composite layer formed thereon, and laminating the composite sheet, thereby changing the adhesive strength of the adhesive layer before and after irradiation with ultraviolet light. Therefore, the adhesive strength between the ceramic layer and the support holding the ceramic layer can be large when the ceramic layer is held and small when the support is peeled off, so that the production of the composite sheet and the lamination using the composite sheet can be performed. It can be easily performed in a stable state. Further, similarly to the above, the time required for manufacturing the laminate can be further reduced, and the productivity can be improved.
[0023]
In the invention according to claim 6 of the present invention, in particular, a plurality of internal electrode layers are formed on a support via an adhesive layer containing an ultraviolet curable resin, and the internal electrode layers and the internal electrode layers are formed. After bonding the step suppressing ceramic layer so as to cover the entire surface including the unprocessed portion, by removing the step suppressing ceramic layer on the internal electrode layer, the internal electrode layer on the support body A method of manufacturing a laminated ceramic electronic component, comprising the steps of forming a composite layer comprising a step-reducing ceramic layer and alternately laminating the composite layer and the ceramic layer, whereby adhesiveness is obtained before and after irradiation with ultraviolet light. The adhesive strength of the layer can be changed, and therefore, the adhesive strength between the internal electrode layer and the step suppressing ceramic layer and the support holding the same is large when the step suppressing ceramic layer is formed. Since it can be made small when peeling off, the ceramic layer for suppressing steps can be sufficiently adhered to the adhesive layer, and the ceramic layer for suppressing steps can be accurately formed on the portion where the internal electrode layer is not formed, and the support Can be easily peeled off.
[0024]
The invention according to claim 7 of the present invention is particularly directed to a method for removing a step-reducing ceramic layer on an internal electrode layer, the method comprising: disposing an adhesive layer on the step-reducing ceramic layer; A step for removing the step-reducing ceramic layer on the electrode layer, wherein the adhesive strength between the formation object forming the internal electrode layer and the internal electrode layer is A, and the adhesive strength between the internal electrode layer and the step-reducing ceramic layer is B, the adhesive strength between the body on which the internal electrode layer is formed and the step-reducing ceramic layer is C, the adhesive strength between the step-reducing ceramic layer and the adhesive layer is D, and the step is suppressed. When the sheet strength of the ceramic layer for use is E, the relationship between the respective strengths is A> B, D> B, and C>D> E. To reduce the level difference on the internal electrode layer. Click layer can reliably and accurately removed and a ceramic layer stepped suppression portion is not formed in the internal electrode layers can be precisely and easily formed.
[0025]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a multilayer ceramic capacitor which is one of the multilayer ceramic electronic components will be described as an example.
[0026]
(Embodiment 1)
Hereinafter, the first embodiment of the present invention will be described with reference to the first embodiment.
[0027]
Embodiment 1 of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view for explaining a manufacturing process of the laminated green block according to the first embodiment. In FIG. 1, 11 is a ceramic layer for suppressing a step, 12 is an internal electrode layer, 13 is a ceramic layer, 14 is a base film, and 15 is an adhesive layer.
[0028]
Hereinafter, a method for manufacturing the multilayer ceramic capacitor according to the first embodiment will be described.
[0029]
First, 5 parts by weight or more and 10 parts by weight or less of an organic binder such as polyvinyl butyral and a plasticizer such as a phthalate ester are added to 100 parts by weight of a raw material powder mainly composed of a dielectric ceramic powder such as barium titanate. 1 to 5 parts by weight and an appropriate amount of an organic solvent such as butyl acetate were mixed to prepare a ceramic slurry.
[0030]
Next, a ceramic slurry is applied and dried on the carrier film by a sheet forming method such as a doctor blade or a lip coater, and the ceramic layer 11 for suppressing a step having a thickness of 2 μm, and separately from the ceramic layer 11 for controlling a step, A 10 μm ceramic layer 13 and a 50 μm ceramic layer 13 were formed on the carrier film.
[0031]
Next, as shown in FIG. 1A, the ceramic layer 13 having a thickness of 50 μm is formed from the carrier film side at a temperature of 50 ° C. to 100 ° C., which is equal to or higher than the glass transition point of the organic binder component contained in the ceramic layer 13. Thereafter, the carrier film was peeled off by heating and pressing under a pressure of 5 MPa to 15 MPa and bonded to a pedestal surface (not shown). Next, after further laminating a ceramic layer 13 having a thickness of 50 μm thereon, the operation of peeling off the carrier film is repeatedly performed, and the ceramic layers 13 are stacked so as to have a predetermined number, thereby forming a lower ineffective layer portion. The ceramic layer 13 was produced.
[0032]
Next, an organic binder such as ethyl cellulose is used in an amount of 3 to 8 parts by weight and an organic solvent such as terpineol is added in an appropriate amount to 100 parts by weight of a metal powder such as Ni on the ceramic layer 13 serving as a lower ineffective layer. The mixed internal electrode paste was screen-printed in a predetermined pattern and then dried to form a plurality of 2 μm-thick internal electrode layers 12 on the same surface.
[0033]
Next, on the plurality of internal electrode layers 12 formed on the ceramic layer 13, the 2 μm-thick ceramic layer 11 for suppressing a step formed on the carrier film is peeled off from the carrier film, and the peeled surface faces down. As shown in FIG. 1B, the internal electrode layer 12 and the portion of the ceramic layer 13 where the internal electrode layer 12 was not formed were bonded so as to cover the ceramic layer 13. In addition, an elastic rubber roller or the like is used at a low pressure to prevent air bubbles from remaining between the step-reducing ceramic layer 11 and the internal electrode layer 12 and the ceramic layer 13 where the internal electrode layer 12 is not formed. Air bubbles were removed by lightly pressing the step-reducing ceramic layer 11.
[0034]
Here, since the step suppressing ceramic layer 11 is not a specific pattern but a sheet having a uniform thickness with respect to the internal electrode layer 12, precise positioning of the step suppressing ceramic layer 11 with respect to the internal electrode layer 12 is performed. Is not required. Therefore, bonding can be performed very easily.
[0035]
Next, as shown in FIG. 1C, an acrylic resin-based adhesive layer 15 having a thickness of 50 μm formed on the base film 14 is bonded on the bonded step-reducing ceramic layer 11, and In order that the electrode layer 12 and the ceramic layer 11 for suppressing a level difference do not adhere to each other, the temperature is not higher than the glass transition point of the organic binder component contained in the internal electrode layer 12 and not higher than 10 ° C. and not higher than 30 ° C .; It crimped on condition of.
[0036]
Next, as shown in FIG. 1D, the base film 14 and the adhesive layer 15 are peeled off, and only the step suppressing ceramic layer 11 on the internal electrode layer 12 is adhered to the adhesive layer 15 and removed. By forming the step suppressing ceramic layer 11 between the adjacent internal electrode layers 12, as shown in FIG. 1E, the step due to the presence or absence of the internal electrode layer was suppressed.
[0037]
Here, in order to easily form the step suppressing ceramic layer 11 between the adjacent internal electrode layers 12 by removing the step suppressing ceramic layer 11 on the internal electrode layer 12, the adhesive strength of the interface of each layer is required. The point is the magnitude relationship between the sheet strengths of the step suppressing ceramic layer 11.
[0038]
Hereinafter, the results of measuring the adhesive strength at the interface between the ceramic layer 11, the internal electrode layer 12, the ceramic layer 13, and the adhesive layer 15 in the first embodiment and the sheet strength of the ceramic layer 11 in the first embodiment will be described. Will be described.
[0039]
Here, the adhesive strength between the internal electrode layer 12 and the ceramic layer 13 is the adhesive strength A1, the adhesive strength between the internal electrode layer 12 and the step-reducing ceramic layer 11 is the adhesive strength B1, and the step-reducing ceramic layer 11 is The adhesive strength between the adhesive layer and the ceramic layer 13 is represented by adhesive strength C1, the adhesive strength between the step-reducing ceramic layer 11 and the adhesive layer 15 is represented by adhesive strength D1, and the sheet strength of the step-reducing ceramic layer 11 is represented by sheet strength E1. I do.
[0040]
The adhesive strength A1 is the strength when an adhesive tape is stuck on the internal electrode layer 12 formed on the ceramic layer 13 under the same conditions as the first embodiment, and the adhesive tape is peeled off in the 180 ° direction. It was determined by measuring. Similarly, in the case of the adhesive strength B1 and the adhesive strength C1, after the respective layers are bonded under the same conditions as in the first embodiment, an adhesive tape is bonded to one surface and pulled in the 180 ° direction. It was determined by measuring the strength when peeled off. The adhesive strength D1 is obtained by bonding the step-reducing ceramic layer 11 on the adhesive layer 15 formed on the base film 14 under the same conditions as in the first embodiment, and then bonding an adhesive tape thereon. And the strength when peeled off in the 180 ° direction. The sheet strength E1 was determined by measuring the tensile strength in the 180 ° direction of the step suppressing ceramic layer 11. The results of these strength measurements are shown in Table 1.
[0041]
[Table 1]

[0042]
As shown in Table 1, when the adhesive strength B1 is made smaller than the adhesive strength A1 and the adhesive strength D1, the internal electrode layer 12 is peeled off when the step-reducing ceramic layer 11 on the internal electrode layer 12 is peeled off. It is possible to easily remove only the step-reducing ceramic layer 11 on the internal electrode layer 12 without peeling off the internal electrode layer 12. In the first embodiment, since the internal electrode layer 12 is formed by printing and drying the internal electrode paste on the ceramic layer 13, the interface between the internal electrode layer 12 and the ceramic layer 13 is strongly adhered. The strength A1 is larger than the adhesive strength at the interface between the internal electrode layer 12 and the adhesive tape bonded thereon. Since the adhesive tape was peeled off from the internal electrode layer 12 first, it exceeded the measurement upper limit, and the internal electrode layer 12 Layer 12 did not peel.
[0043]
Further, the adhesive strength B1 is determined by the fact that the surface of the step suppressing ceramic layer 11 separated from the carrier film and the surface of the internal electrode layer 12 where the organic binder component is relatively sparse are bonded. Since the glass was compression-bonded at a temperature of 10 ° C. or higher and 30 ° C. or lower and a pressure of 0.1 MPa or higher and 10 MPa or lower at a temperature below the glass transition point of the organic binder component included in the organic binder component, it hardly adhered, so Thus, the ceramic layer 11 for suppressing the step on the internal electrode layer 12 could be easily removed.
[0044]
Here, assuming that the adhesive strength B1 ≧ the adhesive strength A1, when the step suppressing ceramic layer 11 on the internal electrode layer 12 is removed, the internal electrode layer 12 is also removed at the same time, and desired electrical characteristics cannot be obtained. Not so desirable. If the adhesive strength B1 is equal to or greater than the adhesive strength D1, the step-reducing ceramic layer 11 to be removed on the internal electrode layer 12 remains, and the thickness of the ceramic effective layer between the internal electrode layers 12 is changed to obtain desired electrical characteristics. Is not obtained, which is not desirable.
[0045]
Therefore, in order to easily remove the step-reducing ceramic layer 11 on the internal electrode layer 12, the adhesive strength B1 needs to be smaller than the adhesive strength A1 and the adhesive strength D1.
[0046]
Next, by increasing the adhesive strength C1 as compared with the adhesive strength D1, when the step-reducing ceramic layer 11 on the internal electrode layer 12 is peeled off, the step-reducing ceramic between adjacent internal electrode layers 12 is removed. The layer 11 can be easily formed without being removed. In the first embodiment, the ceramic layer 13 and the step suppressing ceramic layer 11 between the adjacent internal electrode layers 12 are bonded to each other by peeling the surfaces of the carrier film having a relatively dense organic binder component from each other. Therefore, it is sufficiently adhered even when pressed under a low pressure under the condition of a temperature of 10 ° C. or more and 30 ° C. or less and a pressure of 0.1 MPa or more and 10 MPa or less, and is used for suppressing a step with the ceramic layer 13 between the adjacent internal electrode layers 12. The adhesive strength C1 with the ceramic layer 11 is large. Also, by reducing the sheet strength E1 of the step suppressing ceramic layer as compared with the adhesive strength D1, only the step suppressing ceramic layer 11 on the internal electrode layer 12 is removed, and the gap between the adjacent internal electrode layers 12 is reduced. Thus, it is possible to easily form the ceramic layer 11 for suppressing steps.
[0047]
Here, if the adhesive strength D1 ≧ the adhesive strength C1, the ceramic layer 11 for suppressing a level difference to be left between the adjacent internal electrode layers 12 is undesirably adhered to the adhesive layer 15 and removed. If the sheet strength E1 is equal to or greater than the adhesive strength D1, the step-reducing ceramic layer 11 on the internal electrode layer 12 is separated from the adhesive layer 15, and the patterning of the step-reducing ceramic layer 11 cannot be performed. It is not desirable because it remains on the upper surface and changes the thickness of the ceramic effective layer between the internal electrode layers 12 so that desired electrical characteristics cannot be obtained. Accordingly, in order to accurately form the step-reducing ceramic layer, it is desirable that the sheet strength E1 be smaller than the adhesive strength D1.
[0048]
As described above, the step-reducing ceramic layer 11 is formed on the plurality of internal electrode layers 12 formed on the ceramic layer 13 using the magnitudes of the adhesive strengths A1, B1, C1, D1 and the sheet strength E1. After being bonded so as to cover the entire surface of the portion where the internal electrode layer 12 and the internal electrode layer 12 are not formed, only the step suppressing ceramic layer 11 on the internal electrode layer 12 is removed, and the space between the adjacent internal electrode layers 12 is removed. In order to form the ceramic layer 11 for suppressing steps, the relationship of the respective strengths is as follows: adhesive strength A1> adhesive strength B1, adhesive strength D1> adhesive strength B1, and adhesive strength C1> adhesive strength D1> sheet The strength must be E1, and by satisfying the magnitude relation of these strengths, the step-reducing ceramic layer 11 on the internal electrode layer 12 is removed and the internal electrode layer 12 is removed. Since the step-reducing ceramic layer 11 can be left in a non-existent portion, the step can be suppressed without causing a displacement due to the overlapping of the internal electrode layer 12 and the step-reducing ceramic layer 11, which has been a problem in the conventional technology. The ceramic layer 11 for use can be easily patterned.
[0049]
Next, as shown in FIG. 1F, the ceramic layer 13 having a thickness of 10 μm formed on the carrier film is thermocompression-bonded under the conditions of a temperature of 50 ° C. or more and 100 ° C. or less and a pressure of 5 MPa or more and 15 MPa or less. The film was peeled off to form a ceramic layer 13 serving as an effective layer.
[0050]
Next, on the above-mentioned ceramic layer 13, the formation of the internal electrode layer 12, the formation of the step-reducing ceramic layer 11, and the formation of the ceramic layer 13 are performed in the same manner as shown in FIGS. 1 (a) to 1 (f). By repeating the steps of forming the above, 101 internal electrode layers 12 and ceramic layers 11 for suppressing a level difference and 100 ceramic layers 13 were laminated to obtain a state shown in FIG.
[0051]
Next, on the state shown in FIG. 1 (g), a ceramic layer 13 having a thickness of 50 μm is laminated, heated and pressed, and then the operation of peeling the carrier film is repeated, and a predetermined number of sheets are overlaid to form an upper ineffective layer portion. Was formed to produce a laminate green block shown in FIG. 1 (h).
[0052]
Next, the produced laminated green block was cut into a predetermined size to obtain individual pieces, thereby producing a laminated green chip. Next, the obtained laminated green chip was degreased and fired under a predetermined atmosphere and temperature, and external electrodes were formed on both exposed end faces of the internal electrode layer to obtain a finished multilayer ceramic capacitor.
[0053]
In the multilayer ceramic capacitor according to the first embodiment, the internal electrode layer 12 and the step suppressing ceramic layer 11 can be accurately and easily laminated. And the occurrence of structural defects could be suppressed.
[0054]
Further, since the ceramic layer 11 having the same composition as the ceramic layer 13 is used as the ceramic layer 13, the sintering shrinkage behavior of the ceramic layer 11 and the ceramic layer 13 when the laminated body is fired is stabilized. Structural defects are less likely to occur.
[0055]
Further, in the first embodiment, the unevenness of the distribution of the organic binder component generated in the thickness direction of the ceramic layers 11, the ceramic layers 13, the ceramic layers 13, and the internal electrode layers 12 for the unevenness of the steps is reduced. Of the adhesive strength B1 between the ceramic layer 11 for internal use and the internal electrode layer 12 and the adhesive strength C1 between the ceramic layer 13 on which the internal electrode layer 12 is formed and the ceramic layer 11 for suppressing a level difference are easily controlled. Although the step difference suppressing ceramic layer 11 was formed, the type, the addition amount, the glass transition point, and the like of the organic binder contained in the step difference suppressing ceramic layer 11, the ceramic layer 13, the ceramic layer 13, and the internal electrode layer 12 were changed. The same effect can be obtained by controlling the adhesive strength of each interface.
[0056]
In the first embodiment, the thickness of the ceramic layer 11 for suppressing a level difference is set to be approximately the same as that of the internal electrode layer 12, that is, 2 μm, and the same number of ceramic layers 11 for suppressing the level difference are formed as the internal electrode layer 12. There is no particular limitation on the thickness and the number of layers of the suppression ceramic layer 11, and it is desirable to set the thickness to 30% to 120% of the total thickness of the internal electrode layers. More desirably, it is desirably determined in the range of 50% to 100%. Further, by controlling the above-mentioned adhesive strengths B, C, D and sheet strength E in an appropriate range, such as the kind of organic binder contained in each layer, the amount added, and the glass transition point, etc., the ceramic for suppressing a step having a greater thickness can be obtained. It is also possible to improve the productivity by forming the layer 11 at one time and reducing the number of times of forming the step suppressing ceramic layer.
[0057]
Further, in order to accurately form a boundary between the step-reducing ceramic layers 11 between the adjacent internal electrode layers 12, the step-reducing ceramic layers 11 may be previously covered with the internal electrode layers 12 and the entire portion without the internal electrode layers. It is desirable that the whole is uniformly press-compressed with an elastic rubber or the like so that the ceramic layer 11 for suppressing steps is uniformly adhered to the ceramic layer 13 on the outer peripheral portion of the internal electrode layer 12.
[0058]
(Embodiment 2)
Hereinafter, the second embodiment of the present invention will be described with reference to the second embodiment.
[0059]
Embodiment 2 of the present invention will be described with reference to the drawings. FIG. 2 is a cross-sectional view for explaining a manufacturing process of the stacked green block according to the second embodiment. 2, reference numeral 11 denotes a ceramic layer for suppressing a step, 13 denotes a ceramic layer, 14 denotes a base film, 15 denotes an adhesive layer, 22 denotes an internal electrode layer, and 26 denotes a support film.
[0060]
Hereinafter, a method for manufacturing the multilayer ceramic capacitor according to the second embodiment will be described. Here, the base film 14 and the adhesive layer 15 were the same as in the first embodiment, and the step suppressing ceramic layer 11 and the ceramic layer 13 were the same as those in the first embodiment. Are assigned the same numbers, and the details are omitted. Further, the internal electrode paste used for forming the internal electrode layer 22 is the same as that of the first embodiment, and thus detailed description is omitted.
[0061]
First, as shown in FIG. 2A, the internal electrode paste used in the first embodiment is screen-printed in a predetermined pattern on a support film 26 serving as a support, and then dried to form a 2 μm thick internal electrode paste. A plurality of layers 22 were formed.
[0062]
Next, as shown in FIG. 2B, the 2 μm-thick ceramic layer 11 having a thickness of 2 μm formed on the carrier film is formed on the plurality of internal electrode layers 22 formed on the support film 26 from the carrier film. The internal electrode layer 22 and the portion where the internal electrode layer 22 was not formed were attached so that the peeled surface was on the lower side.
[0063]
Next, as shown in FIG. 2C, an acrylic resin-based adhesive layer 15 having a thickness of 50 μm formed on a base film 14 was formed on the bonded ceramic layer 11 for suppressing a step, at a temperature of 10 ° C. or higher and 30 ° C. or higher. Pressure bonding was performed at a temperature of not more than 0 ° C. and a pressure of 0.1 MPa to 10 MPa.
[0064]
Next, as shown in FIG. 2D, the base film 14 and the adhesive layer 15 are peeled off, and the step-reducing ceramic layer 11 on the internal electrode layer 22 is adhered to the adhesive layer 15 and removed. By leaving the step-reducing ceramic layer 11 between the adjacent internal electrode layers 22, a step-repressed composite layer composed of the internal electrode layer 22 and the step-reducing ceramic layer 11 is formed on the support film 26. The state shown in FIG. 2 (e) was obtained. A plurality of these were produced.
[0065]
Here, the adhesive strength between the internal electrode layer 22 and the support film 26 is adhesive strength A2, the adhesive strength between the internal electrode layer 22 and the ceramic layer 11 for level difference is adhesive strength B2, and the ceramic layer 11 for level difference The adhesive strength between the support film 26 and the support film 26 is referred to as adhesive strength C2, the adhesive strength between the step-reducing ceramic layer 11 and the adhesive layer 15 is referred to as adhesive strength D2, and the sheet strength of the step-reducing ceramic layer 11 is referred to as sheet strength E2. Table 2 shows the results obtained by measuring the adhesive strength between the layers and the sheet strength E2 of the ceramic layer for suppressing a level difference in the second embodiment in the same manner as in the first embodiment.
[0066]
[Table 2]

[0067]
As shown in (Table 2), the relationship between the strengths is as follows: adhesive strength A2> adhesive strength B2, adhesive strength D2> adhesive strength B2, and adhesive strength C2> adhesive strength D2> sheet strength E2. I did it. Accordingly, in the second embodiment, the step-reducing ceramic layer 11 on the internal electrode layer 22 can be removed and the step-reducing ceramic layer 11 can be left in a portion where the internal electrode layer 22 is not provided. The patterning of the step suppressing ceramic layer 11 between the internal electrode layers 22 could be easily performed without causing the problem of the displacement which was a problem in the technique of (1).
[0068]
On the other hand, in the same manner as in the first embodiment, the ceramic layer 13 having a thickness of 50 μm formed on the carrier film is heat-pressed from the carrier film side under the conditions of a temperature of 50 ° C. or more and 100 ° C. or less and a pressing force of 5 MPa or more and 15 MPa or less. After bonding to a surface (not shown), the operation of peeling off the carrier film was repeatedly performed, and the ceramic layers 13 were stacked so as to have a predetermined number to form the ceramic layer 13 to be the lower ineffective layer portion.
[0069]
Then, the composite layer formed on the support film 26 shown in FIG. 2E is formed on the ceramic layer 13 of the lower ineffective layer portion at a temperature of 50 ° C. to 100 ° C. and a pressure of 5 MPa to 15 MPa from the support film 26 side. After thermocompression bonding under the conditions described above, the support film 26 was peeled off as shown in FIG.
[0070]
Next, the ceramic layer 13 having a thickness of 10 μm formed on the carrier film was formed on the composite layer including the internal electrode layer 22 formed on the ceramic layer 13 in the lower ineffective layer portion and the step-reducing ceramic layer 11. After thermocompression bonding from the film side under the conditions of a temperature of 50 ° C. or more and 100 ° C. or less and a pressure of 5 MPa or more and 15 MPa or less, the carrier film was peeled off to obtain a state shown in FIG.
[0071]
Subsequently, the steps of FIGS. 2 (f) and 2 (g) described above are repeated, and 101 internal electrode layers 22 and the ceramic layer 11 for suppressing a level difference, and 100 ceramic layers 13 are laminated. The state shown in FIG.
[0072]
Next, a ceramic layer 13 having a thickness of 50 μm is laminated on the state shown in FIG. Was formed, and a laminated green block shown in FIG. 2 (i) was produced.
[0073]
Next, in the same manner as in the first embodiment, the laminated green block shown in FIG. 2 (i) was cut into a predetermined size to obtain individual pieces to produce a laminated green chip. Next, the obtained laminated green chip was degreased and fired under a predetermined atmosphere and temperature, and external electrodes were formed on both exposed end faces of the internal electrode layer to obtain a finished multilayer ceramic capacitor.
[0074]
Also in the multilayer ceramic capacitor of the second embodiment, the internal electrode layer 22 and the ceramic layer 11 for suppressing a level difference can be accurately and easily laminated, so that the level difference due to the presence or absence of the internal electrode layer 22 is reduced. As a result, the occurrence of structural defects could be suppressed.
[0075]
In the second embodiment, a composite layer having a reduced step composed of the internal electrode layer 22 formed on the support film 26 and the step-reducing ceramic layer 11 is prepared in advance, and the composite layer and the ceramic layer 13 are formed. Are alternately stacked, so that the time required for manufacturing a stacked green block can be reduced as compared with the case where the internal electrode layer 22 and the step difference suppressing ceramic layer 11 of Embodiment 1 are separately stacked. And productivity can be improved.
[0076]
(Embodiment 3)
Hereinafter, the third embodiment of the present invention will be described with reference to the third embodiment.
[0077]
Embodiment 3 of the present invention will be described with reference to the drawings. FIG. 3 is a cross-sectional view for describing a manufacturing step of the laminated body green block according to the third embodiment. In FIG. 3, 11 is a ceramic layer for suppressing a step, 13 is a ceramic layer, 14 is a base film, 15 is an adhesive layer, 22 is an internal electrode layer, and 26 is a support film. Since these are all the same as those in Embodiment 2, the same numbers are given and the details are omitted.
[0078]
Hereinafter, a method for manufacturing the multilayer ceramic capacitor according to the third embodiment will be described. Note that the steps from FIG. 3A to FIG. 3E are the same as the steps from FIG. 2A to FIG.
[0079]
As shown in FIG. 3E, after forming a composite layer including the internal electrode layer 22 and the step-reducing ceramic layer 11 on the support film 26, a carrier film is formed on the composite layer of FIG. The ceramic layer 13 having a thickness of 10 μm formed thereon is peeled off from the carrier film, and the peeled surface is bonded downward at a temperature of 10 ° C. or more and 100 ° C. or less and a pressure of 0.1 MPa or more and 15 MPa or less. The composite sheet shown in FIG. 3F in which the electrode layer 22 was embedded and a step due to the presence or absence of the internal electrode layer 22 was suppressed was formed on the support film 26. A plurality of these were produced.
[0080]
The adhesive strength at the interface between the layers and the sheet strength of the ceramic layer 11 for suppressing a step are all the same as those in the above-described second embodiment (Table 2).
[0081]
On the other hand, in the same manner as in the first embodiment, the ceramic layer 13 having a thickness of 50 μm formed on the carrier film is heat-pressed from the carrier film side under the conditions of a temperature of 50 ° C. or more and 100 ° C. or less and a pressing force of 5 MPa or more and 15 MPa or less. After bonding to a surface (not shown), the operation of peeling off the carrier film was repeatedly performed, and the ceramic layers 13 were stacked so as to have a predetermined number to form the ceramic layer 13 to be the lower ineffective layer portion.
[0082]
Next, the composite sheet formed on the support film 26 shown in FIG. 3F is applied on the ceramic layer 13 serving as the lower ineffective layer portion at a temperature of 50 ° C. or more and 100 ° C. or less from the support film 26 side. After thermocompression bonding under the conditions of a pressure of 5 MPa or more and 15 MPa or less, the support film 26 was peeled off as shown in FIG.
[0083]
Subsequently, the above-described step of FIG. 3G in which the composite sheet formed on the support film 26 of FIG. 3F is thermocompression-bonded as described above is repeatedly performed, so that the internal electrode layer 22 and the step-reducing ceramic layer are formed. 3 and 100 ceramic layers 13 were laminated to obtain the state shown in FIG.
[0084]
Next, a ceramic layer 13 having a thickness of 50 μm is laminated on the state shown in FIG. Was formed to produce a laminate green block shown in FIG.
[0085]
Next, in the same manner as in the first embodiment, the laminated green block shown in FIG. 3 (i) was cut into a predetermined size to obtain individual pieces to produce a laminated green chip. Next, the obtained laminated green chip was degreased and fired under a predetermined atmosphere and temperature, and external electrodes were formed on both exposed end faces of the internal electrode layer to obtain a finished multilayer ceramic capacitor.
[0086]
Also in the multilayer ceramic capacitor of the third embodiment, the internal electrode layer 22 and the ceramic layer 11 for suppressing a step can be accurately and easily laminated, so that the step due to the presence or absence of the internal electrode layer 22 is reduced. As a result, the occurrence of structural defects could be suppressed.
[0087]
In the third embodiment, a composite sheet including the internal electrode layer 22 formed on the support film 26 and the ceramic layer 11 for suppressing a level difference, and a composite sheet in which the ceramic layer 13 is laminated thereon are prepared in advance. Since this composite sheet is laminated, the time required for producing the laminated green block can be shortened and the productivity can be improved as compared with the second embodiment.
[0088]
(Embodiment 4)
Hereinafter, a fourth embodiment of the present invention will be described with reference to the fourth embodiment.
[0089]
Embodiment 4 of the present invention will be described with reference to the drawings. FIG. 4 is a cross-sectional view for describing a manufacturing step of the stacked green block according to the fourth embodiment. In FIG. 4, 11 is a ceramic layer for suppressing a level difference, 13 is a ceramic layer, 14 is a base film, 15 is an adhesive layer, 42 is an internal electrode layer, 46 is a support film, and 47 is an adhesive layer containing an ultraviolet curable resin. .
[0090]
Hereinafter, a method for manufacturing the multilayer ceramic capacitor according to the fourth embodiment will be described. Here, the base film 14 and the adhesive layer 15 were the same as in the first embodiment, and the step suppressing ceramic layer 11 and the ceramic layer 13 were the same as those in the first embodiment. Are assigned the same numbers, and the details are omitted. Further, the same internal electrode paste used in the formation of the internal electrode layer 42 as that of the first embodiment is used, and therefore detailed description is omitted.
[0091]
First, a 10-μm-thick ceramic layer 13 formed on a carrier film was bonded onto an adhesive layer 47 containing an ultraviolet-curable resin formed on a support film 46 serving as a support, and the carrier film was peeled off. Next, a plurality of 2 μm-thick internal electrode layers 42 were formed on the ceramic layer 13 in the same manner as in the first embodiment, and the state shown in FIG. 4A was obtained.
[0092]
As the adhesive layer 47 containing an ultraviolet curable resin, the adhesive strength with the ceramic layer 13 is measured by the same method as in the first embodiment, and before the ultraviolet irradiation, the adhesive strength is 10 N / cm or more. And a material which becomes 0.5 N / cm or less after curing by irradiation with ultraviolet rays was used.
[0093]
Next, on the ceramic layer 13 on which the plurality of internal electrode layers 42 were formed, the ceramic layer 13 was formed on the carrier film so as to cover the internal electrode layers 42 and the portion of the ceramic layer 13 where the internal electrode layers 42 were not formed. The 2 μm-thick step-reducing ceramic layer 11 was peeled off from the carrier film, and the peeled surface was attached downward, as shown in FIG. 4B. Then, pressure bonding was performed under conditions of a temperature of 10 ° C. or more and 30 ° C. or less and a pressure of 0.1 MPa or more and 10 MPa or less.
[0094]
Next, as shown in FIG. 4C, an acrylic resin-based adhesive layer 15 having a thickness of 50 μm formed on the base film 14 is bonded on the bonded step suppressing ceramic layer 11, Crimping was carried out under the conditions of not less than 30 ° C. and not more than 0.1 MPa and not more than 10 MPa.
[0095]
Next, as shown in FIG. 4D, the base film 14 and the adhesive layer 15 are peeled off, and the step-reducing ceramic layer 11 on the internal electrode layer 42 is adhered to the adhesive layer 15 and removed. The internal electrode layer 42 and the step-reducing ceramic layer 11 were formed on the ceramic layer 13 formed on the support film 46 via the layer 47, and a plurality of composite sheets shown in FIG. 4E were produced.
[0096]
Here, the adhesive strength between the internal electrode layer 42 and the ceramic layer 13 is the adhesive strength A4, the adhesive strength between the internal electrode layer 42 and the step-reducing ceramic layer 11 is the adhesive strength B4, and the step-reducing ceramic layer 11 is used. The adhesive strength between the adhesive layer and the ceramic layer 13 is referred to as adhesive strength C4, the adhesive strength between the step-reducing ceramic layer 11 and the adhesive layer 15 is referred to as adhesive strength D4, and the sheet strength of the step-reducing ceramic layer 11 is referred to as sheet strength E4. Table 3 shows the results obtained by measuring the adhesive strength of each layer and the sheet strength E4 of the ceramic layer for suppressing a level difference in the fourth embodiment in the same manner as in the first embodiment.
[0097]
[Table 3]

[0098]
As shown in (Table 3), the relationship between the strengths is as follows: adhesive strength A4> adhesive strength B4, adhesive strength D4> adhesive strength B4, and adhesive strength C4> adhesive strength D4> sheet strength E4. I did it. Thereby, also in the fourth embodiment, the step-reducing ceramic layer 11 on the internal electrode layer 42 is removed, and the step-reducing ceramic layer 11 is left on the ceramic layer 13 in a portion where the internal electrode layer 42 does not exist. Therefore, the patterning of the step-reducing ceramic layer 11 between the internal electrode layers 42 could be easily performed without causing the problem of the displacement which was a problem in the conventional technology.
[0099]
Further, in the step of producing the composite sheet, the ceramic layer 13 is held on the support film 46 with a sufficient adhesive strength by the adhesive layer 47 containing the ultraviolet curable resin, so that the composite sheet can be produced stably. did it.
[0100]
On the other hand, in the same manner as in the first embodiment, the ceramic layer 13 having a thickness of 50 μm formed on the carrier film is heat-pressed from the carrier film side under the conditions of a temperature of 50 ° C. or more and 100 ° C. or less and a pressing force of 5 MPa or more and 15 MPa or less. After bonding to a surface (not shown), the operation of peeling off the carrier film was repeatedly performed, and the ceramic layers 13 were stacked so as to have a predetermined number to form the ceramic layer 13 to be the lower ineffective layer portion.
[0101]
Next, the composite sheet formed on the support film 46 via the adhesive layer 47 shown in FIG. 4E is placed on the ceramic layer 13 serving as the lower ineffective layer portion at a temperature of 50 ° C. from the support film 46 side. The thermocompression bonding was carried out under the conditions of not less than 100 ° C. and the applied pressure of not less than 5 MPa and not more than 15 MPa. Then, after the adhesive layer 47 was cured by irradiating ultraviolet rays from the support film 46 side, the support film 46 was peeled off together with the adhesive layer 47 as shown in FIG. At this time, the adhesive strength between the adhesive layer 47 and the ceramic layer 13 was extremely reduced by the irradiation of the ultraviolet light, and the support film 46 and the adhesive layer 47 could be easily peeled off.
[0102]
Subsequently, the above-described step of FIG. 4F in which the composite sheet formed on the support film 46 through the adhesive layer 47 of FIG. Then, 101 ceramic layers 11 and 100 ceramic layers 13 were stacked to obtain the state shown in FIG.
[0103]
Next, on the state shown in FIG. 4 (g), a ceramic layer 13 having a thickness of 50 μm is laminated, heated and pressed, and then the operation of peeling the carrier film is repeated, and a predetermined number of sheets are superposed to form an upper ineffective layer portion. Was formed to produce a laminate green block shown in FIG.
[0104]
Next, in the same manner as in the first embodiment, the laminated green block shown in FIG. 4 (h) was cut into a predetermined size to obtain individual pieces to produce a laminated green chip. Next, after the obtained laminated green chip is degreased and fired in a predetermined atmosphere and temperature, external electrodes are formed on both exposed end surfaces of the internal electrode layer, thereby completing the laminated ceramic capacitor in the fourth embodiment. I got the goods.
[0105]
Also in the multilayer ceramic capacitor of the fourth embodiment, the internal electrode layer 42 and the ceramic layer 11 for suppressing a level difference can be formed with high precision and can be easily laminated. And the occurrence of structural defects was suppressed.
[0106]
In the fourth embodiment, since a composite sheet is prepared in advance and the composite sheet is laminated, the time required for producing a laminate green block can be reduced as in the third embodiment, and productivity can be reduced. Was improved.
[0107]
(Embodiment 5)
Hereinafter, a fifth embodiment of the present invention will be described with reference to a fifth embodiment.
[0108]
Embodiment 5 of the present invention will be described with reference to the drawings. FIG. 5 is a cross-sectional view for describing a manufacturing step of the laminated body green block according to the fifth embodiment. In FIG. 5, 11 is a ceramic layer for suppressing a step, 13 is a ceramic layer, 14 is a base film, 15 is an adhesive layer, 46 is a supporting film, and 47 is an adhesive layer containing an ultraviolet curable resin. Since these are all the same as those in Embodiment 4, the same numbers are assigned and the details are omitted. 52 is an internal electrode layer.
[0109]
Hereinafter, a method for manufacturing the multilayer ceramic capacitor according to the fifth embodiment will be described.
[0110]
First, a 2 μm-thick ceramic layer 11 for suppressing a step formed on a carrier film is placed on an acrylic resin-based pressure-sensitive adhesive layer 15 formed on a base film 14, and the ceramic layer 11 for suppressing a step and the acrylic resin-based pressure-sensitive adhesive layer 15 face each other. After bonding, the carrier film on the side of the ceramic layer 11 for suppressing a level difference was peeled off to obtain a state shown in FIG.
[0111]
On the other hand, a plurality of internal electrode layers 52 having a thickness of 2 μm were formed on the adhesive layer 47 containing an ultraviolet curable resin formed on a support film 46 serving as a support, and the state shown in FIG. 5B was obtained. . The adhesive strength between the adhesive layer 47 containing the ultraviolet curable resin and the internal electrode layer 52 is equal to or higher than the measurement limit upper limit of 10 N / cm or more before irradiation with ultraviolet light, and is 0.5 N / cm after irradiation with ultraviolet light. Was used.
[0112]
Next, the side of the internal electrode layer 52 in FIG. 5B and the side of the step-reducing ceramic layer 11 in FIG. 5A are bonded together. 5C to obtain the state shown in FIG.
[0113]
Next, as shown in FIG. 5D, the base film 14 and the adhesive layer 15 are peeled off, and the step-reducing ceramic layer 11 on the internal electrode layer 52 is adhered to the adhesive layer 15 and removed. By leaving the step-reducing ceramic layer 11 between the adjacent internal electrode layers 52, the composite layer of the step-suppressed ceramic layer 11 composed of the internal electrode layer 52 and the step-reducing ceramic layer 11 is supported by the support film 46 via the adhesive layer 47. 5 (e). A plurality of these were produced.
[0114]
Here, the adhesive strength between the internal electrode layer 52 and the adhesive layer 47 is the adhesive strength A5, the adhesive strength between the internal electrode layer 52 and the ceramic layer 11 for suppressing the step is adhesive strength B5, and the ceramic layer 11 for controlling the step. The adhesive strength between the adhesive layer 47 and the adhesive layer 47 is referred to as adhesive strength C5, the adhesive strength between the step-reducing ceramic layer 11 and the adhesive layer 15 is referred to as adhesive strength D5, and the sheet strength of the step-reducing ceramic layer 11 is referred to as sheet strength E5. Table 4 shows the results obtained by measuring the adhesive strength of each layer and the sheet strength E5 of the step suppressing ceramic layer in the fifth embodiment in the same manner as in the first embodiment.
[0115]
[Table 4]

[0116]
As shown in (Table 4), the relationship between the strengths is as follows: adhesive strength A5> adhesive strength B5, adhesive strength D5> adhesive strength B5, and adhesive strength C5> adhesive strength D5> sheet strength E5. I did it. Thus, also in the fifth embodiment, the step-reducing ceramic layer 11 on the internal electrode layer 52 can be removed and the step-reducing ceramic layer 11 can be left in a portion where the internal electrode layer 52 does not exist. The ceramic layer 11 for suppressing a level difference can be easily and accurately patterned between the internal electrode layers 52 without causing the problem of the displacement which is a problem in the conventional technology.
[0117]
Next, the ceramic layer 13 having a thickness of 10 μm formed on the carrier film was peeled off from the carrier film on the composite layer shown in FIG. Hereinafter, the composite sheet shown in FIG. 5 (f) in which the internal electrode layer 52 is embedded and the step due to the presence or absence of the internal electrode layer 52 is suppressed is bonded through the adhesive layer 47 by adhering under a pressure of 0.1 MPa or more and 15 MPa or less. And formed on the supporting film 46. A plurality of these were produced.
[0118]
On the other hand, in the same manner as in the first embodiment, the ceramic layer 13 having a thickness of 50 μm formed on the carrier film is heat-pressed from the carrier film side under the conditions of a temperature of 50 ° C. to 100 ° C. and a pressure of 5 MPa to 15 MPa to form After bonding to a surface (not shown), the operation of peeling off the carrier film was repeatedly performed, and the ceramic layers 13 were stacked so as to have a predetermined number to form the ceramic layer 13 to be the lower ineffective layer portion.
[0119]
Next, the composite sheet formed on the support film 46 via the adhesive layer 47 shown in FIG. 5F is placed on the ceramic layer 13 serving as the lower ineffective layer portion at a temperature of 50 ° C. from the support film 46 side. The thermocompression bonding was carried out under the conditions of not less than 100 ° C. and the applied pressure of 5 MPa to 15 MPa. Thereafter, the adhesive layer 47 was cured by irradiating ultraviolet rays from the support film 46 side, and then the support film 46 was peeled off together with the adhesive layer 47 as shown in FIG.
[0120]
Subsequently, the above-described step of FIG. 5G in which the composite sheet formed on the support film 46 is thermocompression-bonded via the adhesive layer 47 of FIG. Then, 101 ceramic layers 11 and 100 ceramic layers 13 were stacked to obtain the state shown in FIG.
[0121]
Next, a ceramic layer 13 having a thickness of 50 μm is laminated on the state shown in FIG. 5 (h), and the operation of peeling off the carrier film is repeated by a predetermined number of sheets, and the upper invalid layer portion is laminated. Was formed to produce a laminate green block shown in FIG. 5 (i).
[0122]
Next, in the same manner as in the first embodiment, the laminated green block shown in FIG. 5 (i) was cut into predetermined dimensions to obtain individual pieces, thereby producing a laminated green chip. Next, after the obtained laminated green chip is degreased and fired in a predetermined atmosphere and temperature, external electrodes are formed on both exposed end surfaces of the internal electrode layer, thereby completing the laminated ceramic capacitor in the fifth embodiment. I got the goods.
[0123]
Also in the multilayer ceramic capacitor of the fifth embodiment, the internal electrode layer 52 and the ceramic layer 11 for suppressing a step can be accurately and easily laminated, so that the step due to the presence or absence of the internal electrode layer 52 is reduced. As a result, the occurrence of structural defects could be suppressed.
[0124]
In the fifth embodiment, since a composite sheet is prepared in advance and the composite sheet is laminated, the time required for producing a laminate green block can be reduced as in the third and fourth embodiments. And improved productivity.
[0125]
With respect to the multilayer ceramic capacitors obtained in the first to fifth embodiments of the present invention described above, the number of occurrences of structural defects and the number of defective capacitances in the internal structure such as cavities and delaminations are each 100. Was confirmed. A capacitor whose capacitance deviated from the designed value by ± 5% or more was regarded as defective. As a result, in each of Embodiments 1 to 5 of the present invention, the number of defects was zero.
[0126]
For comparison, a multilayer ceramic capacitor obtained by the conventional manufacturing method described with reference to FIG. 6 was subjected to the same evaluation. As a result, 13/100 internal structural defects and 6/100 electrostatic capacitance defects were found. Had occurred.
[0127]
From the above, it was confirmed that the multilayer ceramic capacitor manufactured in each of the above-described embodiments is improved in terms of occurrence of structural defects and defective capacitance as compared with the conventional method.
[0128]
In each of the above embodiments, the level difference suppressing ceramic layers are arranged in the same number and at the same positions as the internal electrode layers, but there is no limitation on the number of the level difference suppressing ceramic layers and the arrangement position at the time of lamination. The thickness may be increased to reduce the number of sheets in consideration of the total step difference due to the presence or absence, or the layers may be stacked at equal intervals or randomly.
[0129]
Optimally, the total thickness of the step suppressing ceramic layer is equal to the total thickness of the internal electrode layers.
[0130]
In each of the above embodiments, a multilayer ceramic capacitor has been described as an example. However, a similar effect can be obtained in a multilayer ceramic component in which a ceramic layer and an internal electrode layer are stacked.
[0131]
【The invention's effect】
As described above, the present invention provides a method of manufacturing a multilayer green block of a multilayer ceramic electronic component by alternately laminating ceramic layers and internal electrode layers, wherein a plurality of internal electrode layers patterned on the same surface are provided. After bonding the step suppressing ceramic layer so as to cover the entire surface including the portion where the internal electrode layer is not formed, and removing the step suppressing ceramic layer on the internal electrode layer, the internal electrode is removed. A method for manufacturing a multilayer ceramic electronic component comprising a step of forming a step-reducing ceramic layer in a portion where a layer is not formed and suppressing a step due to the presence or absence of an internal electrode layer. This has the effect of suppressing the occurrence of structural defects, and making it possible to easily obtain a multilayer ceramic component having excellent electrical characteristics with good productivity. .
[Brief description of the drawings]
FIG. 1 is a cross-sectional view for explaining a manufacturing process of a laminated green block according to Embodiment 1 of the present invention.
FIG. 2 is a cross-sectional view for illustrating a manufacturing process of a laminated green block according to Embodiment 2 of the present invention.
FIG. 3 is a cross-sectional view for explaining a manufacturing process of a laminated green block according to Embodiment 3 of the present invention.
FIG. 4 is a cross-sectional view for illustrating a manufacturing process of a laminated green block according to Embodiment 4 of the present invention.
FIG. 5 is a cross-sectional view for illustrating a manufacturing step of the laminated body green block according to the fifth embodiment of the present invention.
FIG. 6 is a cross-sectional view for explaining a manufacturing process of a conventional laminated green block.
[Explanation of symbols]
11 Ceramic layer for suppressing steps
12, 22, 42, 52 Internal electrode layer
13 Ceramic layer
14 Base film
15 Adhesive layer
26, 46 Support film
47 Adhesive layer containing UV curable resin

Claims (7)

In the step of alternately laminating the ceramic layers and the internal electrode layers to form a laminated green block of the multilayer ceramic electronic component, a plurality of patterned internal electrode layers and the internal electrode layer are formed on the same surface. After bonding the step-reducing ceramic layer so as to cover the entire surface including the non-portion part, the step-reducing ceramic layer on the internal electrode layer is removed, so that the part where the internal electrode layer is not formed is formed. A method for manufacturing a multilayer ceramic electronic component, comprising a step of forming a step-reducing ceramic layer to suppress a step due to the presence or absence of an internal electrode layer. A plurality of internal electrode layers are formed on a support, and a step-reducing ceramic layer is attached so as to cover the entire surface including the internal electrode layers and portions where the internal electrode layers are not formed. By removing the step-reducing ceramic layer on the electrode layer, a composite layer composed of an internal electrode layer and a step-reducing ceramic layer is formed on the support, and the composite layer and the ceramic layer are alternately formed. The method for manufacturing a multilayer ceramic electronic component according to claim 1, further comprising a step of laminating. The method for manufacturing a multilayer ceramic electronic component according to claim 2, further comprising a step of laminating a ceramic layer on the composite layer formed on the support to form a composite sheet, and laminating the composite sheet. A ceramic layer is formed on a support, a plurality of internal electrode layers are formed on the ceramic layer, and a step is suppressed so as to cover the entire surface including the internal electrode layer and a portion where the internal electrode layer is not formed. After bonding the ceramic layer for use, the step-reducing ceramic layer on the internal electrode layer is removed to form a composite layer comprising the internal electrode layer and the step-reducing ceramic layer on the ceramic layer on the support. The method for manufacturing a multilayer ceramic electronic component according to claim 1, further comprising the steps of: producing a composite sheet on which is formed, and laminating the composite sheet. The method for manufacturing a multilayer ceramic electronic component according to claim 4, wherein the ceramic layer is formed on the support via an adhesive layer containing an ultraviolet curable resin. The method for manufacturing a multilayer ceramic electronic component according to claim 2, wherein a plurality of internal electrode layers are formed on the support via an adhesive layer containing an ultraviolet curable resin. A method for removing the step-reducing ceramic layer on the internal electrode layer is to dispose the adhesive layer on the step-reducing ceramic layer, peel off the adhesive layer, and remove the step-reducing ceramic layer on the internal electrode layer. The adhesive strength between the substrate on which the internal electrode layer is to be formed and the internal electrode layer is A, the adhesive strength between the internal electrode layer and the step-reducing ceramic layer is B, and the adhesive strength between the internal electrode layer and the internal electrode layer is B. Assuming that the adhesive strength between the formed body and the step-reducing ceramic layer is C, the adhesive strength between the step-reducing ceramic layer and the adhesive layer is D, and the sheet strength of the step-reducing ceramic layer is E, 2. The method for manufacturing a multilayer ceramic electronic component according to claim 1, wherein the relationship of strength is A> B, D> B, and C> D> E. 3.

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