JP3931115B2 - Dielectric resonator and dielectric filter manufacturing method - Google Patents

Description

【００５７】
これらのサンプルＡ〜Ｃを使用して、試験を行なった。試験結果を表１に示す。表１に示すデータから、共振器電極と誘電体基板との間の隙間に僅かでも、接着剤層が浸透すると、Ｑ値が、急激に低下することが判る。このことは、高Ｑ値共振器には、共振器電極と誘電体基板とが直接に接触しなければならないことが判る。
【００５８】
実施形態３．
本発明の誘電体共振器の製造方法は、導電性ペーストを誘電体基板上に塗着して共振器電極に形成する方法を含む。この製造方法においては、実施形態２に示したように、複数のセラミックグリーンシートを積層して、積層板を高温焼結して成形して高ｆＱ値にした誘電体基板を利用する。
【００５９】
この実施形態では、共振器電極のための導電性ペーストを誘電体基板上に塗着するには、第１の誘電体基板の主面に、その誘電体基板上の共振器電極を形成すべき領域を除いて、樹脂接合層を構成するための樹脂接着剤をパターン印刷して、接着剤の層を半硬化する工程を含む。次いで、共振器電極を形成すべき領域に、この接着剤の層をマスクにして、共振器電極とするための導電性ペーストを上記の基板主面上に塗着する工程を含む。
【００６０】
さらに、上記の第１の誘電体基板の共振器電極を形成した面に、第２の誘電体基板の主面を対向させて位置合わせした後、第１及び第２の誘電体基板を外面から加圧しながら加熱して半硬化の樹脂接合層と導電性ペーストとを完全に硬化させて、樹脂接合層と共振器電極と誘電体基板とを一体化させる工程を含む。
【００６１】
図３（ａ）と（ｂ）において、前記の実施形態に示した図２（ａ）と（ｂ）と同様に、強誘電体セラミックのグリーンシート１１は複数枚で積層して焼成することにより誘電体基板１２を作る。この実施形態においては、図３（ｃ）において、誘電体基板は、電極形成面を除いて、他の面には外部電極２３を形成している。
【００６２】
図３（ｄ）の接着剤のパターン形成の工程においては、第１誘電体基板の上面に樹脂接着剤を選択的に印刷塗布して接着剤パターンを形成し、これを予備的に加熱して、樹脂接合層２４をＢステージの半硬化状態とする。
【００６３】
図３（ｅ）は、上記の第１の誘電体基板２２ｂ上のパターン化した樹脂接合層上に、金属粉末を含む導電性ペースト２５を、スキージ２６等により印刷充填し、そのあと、その第１の誘電体基板２２ｂの上に、第２の誘電体基板２２ａを配置する。
【００６４】
図３（ｆ）に示すように両面から加圧、加熱して半硬化状態の樹脂接合層２４と導電性ペースト２５を硬化させることにより、図３（ｇ）に示すように、第１及び第２の誘電体基板２２ａ、２２ｂが共振器電極２７ａ、２７ｂを狭持し、且つ、樹脂接合層２４によって接合された一体構造を有する誘電体共振器を得る。
【００６５】
導電性ペーストには、上述のように、金属粉末と熱硬化性樹脂のバインダとを混練してなる金属ペーストが用いられ、この金属ペーストは、共振器電極の形成と同時に誘電体基板との接着もすることができる。金属には、上述のようにも銀又は銅の粉末が利用される。他の導電性ペーストには、熱分解可能な金属有機物（例えば、金属アルコキシド（Ｍｅ−Ｏ−Ｒ））を用いて、上記の接着剤層によりマスクされた第１の誘電性基板上に塗布した後、加熱により熱分解（ＭＯＤ法）させて、金属をそのパターンに析出させ、共振器電極とすることもできる。
【００６６】
［実施例２］
つぎに、この実施の形態の製造法の誘電体共振器を作った。図３（ａ）と（ｂ）において、Ｂａ−Ｎｄ−Ｔｉ−Ｏ系セラミックグリーンシート１１を複数枚積層して１３５０℃で焼成して、焼結セラミック基板１２を得た。第１及び第２の誘電体基板には、共振器電極形成用の主面を除いて、全ての面に、Ａｇペースト焼き付けて、外部電極２３を形成した。
【００６７】
第１の基板には、主面上にエポキシ樹脂系接着剤を、共振器電極であるストリップラインの形状を残して主面上にパターン印刷して塗布し、加熱し、樹脂接合層２４をＢステージの半硬化状態とした。上記第１の誘電体基板上であって、且つ、該パターン化した樹脂接合層２４が覆っていない面域に、電極形状に切り出した銀箔を嵌め入れて共振器用電極を配置し、その誘電体基板２２ｂの上に第２の誘電体基板２２ａを載せて、二つ合わせにした基板の両外面に３ＭＰａで加圧しながら１５０℃で加温して樹脂ペーストを溶融し硬化させた。これにより、樹脂接合層２４によって一体に接合された誘電体共振器を作った。
【００６８】
比較例は、外部電極２３を焼き付けた同様の焼結誘電体基板を利用して、第１の誘電体基板の主面上に、接着剤としてガラスペーストを、選択的に印刷塗布を行って、パターン化した接合層２４を形成した。以下は、上記実施例と同様にして、接合層２４が覆っていない基板上面に、Ａｇの金属箔を嵌め入れて、その第１の誘電体基板２２ｂの上に第２の誘電体基板２２ａを載せた。この比較例では、両面から３ＭＰａで加圧しながら、但しこの例は、ガラスペーストであるので、６００℃に加熱して、ガラスを溶融させて、接着した。これにより、互いに対面する誘電体基板２２ａ、２２ｂと、共振器電極２７ａ、２７ｂとガラス接合層２４によって接合した誘電体共振器を作った。以下に、実施例と比較例との試験結果を示す。
【００６９】
【表２】

【００７０】
表２に示すように、この実施形態の積層体による共振器構造においては、樹脂接合層として樹脂接着材が、材料が低い接着作業温度と低い弾性率を有することから、共振器電極とセラミックの誘電体基板とを直接接合でき、共振器が高いＱ値を発現することがわかる。
【００７１】
これに対して、比較例においては、ガラス接着層を適用することにより、誘電体基板の相互を溶着させて、高いＱを有する誘電体基板と高導電性を有する共振器電極とを直接接合させた構造としているけれども、実際は、Ｑ特性が低下する結果となっている。比較例は、溶融したガラスが誘電体基板と共振器電極との間に流れ込んで介在しており、電極端部周辺にクラックを発生させていた。クラックは、ガラスとセラミック誘電体との間の熱膨張係数の差により生じたものである。
【００７２】
実施の形態４．
本発明の製造方法には、共振器電極にすべき金属箔と、金属箔の外形を支える刳り抜き部を設けた半硬化接着剤フィルムとから、電極キャリャーフィルムとして、プリプレグ化しておき、該プリフレグを一対の誘電体基板の間に挟んで、加圧下で加熱して一体化する方法を含む。この製造方法は、接着剤フィルムに共振器電極の外形に刳りぬかれた刳り抜き部を設け、該刳り抜き部内に金属箔の共振電極を配置する工程と、該接着剤フィルムを、第１及び第２の誘電体基板の間に配置する工程と、上記の２枚の誘電体基板の外面から加圧しながら加熱して接着剤フィルムを硬化させて樹脂接合層を形成し、誘電体基板と共振器電極とを樹脂接合層により一体化して積層体を形成する工程と、を含んでいる。
【００７３】
上記の接着剤フィルムに多数の刳り抜き部を配置して、各刳り抜き部に共振器電極を配置し、積層体の形成工程の後に、積層体を切断して各誘電体共振器に分離する工程が採用される。
【００７４】
この実施形態は、特に、プリプレグに多数の共振器電極を予め配置して、各共振器電極ごとに上下一対の誘電体基板で挟接して、一体化し、後に、誘電体共振器と成るべき共振器電極を単位にして、電極キャリャーフィルムを切断して分割すれば、多数の誘電体共振器を作ることができる。
【００７５】
図４（ａ）〜（ｃ）には、前述の実施形態と同様に、セラミックグリーンシート１１を複数枚積層して焼成することにより第１及び第２の誘電体基板１２ａ、１２ｂを作る工程を示す。この例も、外部電極が、基板の外面に予め形成してある。
【００７６】
図４（ｄ）には、接着剤フィルムから電極キャリャーフィルムを調製する工程を示すが、半硬化状態にある熱硬化性樹脂フィルム３１に、共振器電極、この例では、ストリップラインの、形状よりやや大きめの形状を有する刳り抜き部、即ち、開口部３２を、多数開設け、各開口部３２にはそれぞれストリップライン３３ａ、３３ｂを、矢示の如く、嵌入して、電極キャリアフィルム３４を作る。この電極キャリアフィルム３４は、共振器電極３３と樹脂接合層３１とを一体に含んでいる。
【００７７】
つぎに、図４（ｅ）に示すように、図４（ａ）〜（ｂ）の工程で作った第１の誘電体基板１２ｂと第２の誘電体基板１２ａとを対向して、その間に、電極キャリアフィルム３４に担持した各共振器電極を挟んで、保持し、基板両面に加圧しながら、加熱して、接着剤フィルムを硬化させる。これにより、誘電体基板と共振器電極および樹脂接合層を積層一体化する
【００７８】
この実施形態では、一対の対向する誘電体基板を、１組の誘電体基板として、各組の誘電体基板は、互いにに分離されている。そこで、図４（ｆ）に示すように、隣接する誘電体基板の間の接着剤フィルムを切断し（図中Ｂ点で）それぞれ個片に、図４（ｇ）に示す誘電体共振器を得る。
【００７９】
この実施の形態においては、樹脂接合層３１は誘電体基板１２の両側面から突出しているが、図４（ｆ）における切断点を変更して、樹脂接合層３１の切断部位が、誘電体基板の端面に面一なるように切断することもできる。
【００８０】
樹脂接合層のための半硬化状態にある接着剤フィルム３１には、加熱によりそれ自体が接着性を有する熱硬化性樹脂が使用され、例えば、エポキシ樹脂が利用できる。また、接着剤フィルムには、上述のように、熱硬化性樹脂、例えば、エポキシ樹脂、に、フィラーとして無機質粉末、例えば、シリカの微粉など、を添加しても良い。
【００８１】
電極キャリアフィルム３４に用いる樹脂接合層として、非接着性樹脂フィルムを用いることもでき、この場合には、フィルムの表面に接着性に優れたエポキシ系の接着剤を薄く塗布することにより誘電体基板同士を接着する。このような非接着性の樹脂フィルムには、ポリエステル樹脂やフッ素樹脂（例えば、ポリテトラフルオロエチレン）などの誘電正接が特に小さくて誘電特性に優れた樹脂フィルムを用いるのが良い。このような樹脂接合層は、電界が入り込んでもＱ値が低下することが殆どないので有利である。
【００８２】
この実施の形態の特徴として、フィルム状の樹脂接合層に共振器電極を配置するための開口部を設けているので、その開口部の形状を、共振器電極の形状より大きくして、樹脂接合層と共振器電極との間に任意の空隙を形成することができ、共振器電極の周囲の樹脂接合層の誘電的性質の影響を低減することができる利点がある。
【００８３】
実施の形態５．
この実施形態について、先の実施形態と同様の電極キャリャーフィルムを使用するものであるが、この実施形態は、第１及び第２の誘電体基板を、多数の共振電極を覆うに十分な大きな外形ものにして、誘電体共振器ないしフィルタの量産性を図るものである。
【００８４】
図５（ａ）と（ｂ）に示すように、誘電体セラミックグリーンシート４１を複数枚積層して後、高温焼成することにより誘電特性の優れて且つ共振器電極の寸法よりも十分に大きい第１及び第２の誘電体基板４２ａ、４２ｂを作る。
【００８５】
図５（ｃ）において、大型の半硬化状態にあるエポキシ樹脂等の熱硬化性樹脂フィルム４３に刳り抜き部、即ち、開口部を配列し、一対のストリップラインの共振器電極４４ａ、４４ｂを開口部に嵌め入れて、電極キャリアフィルム４５を作る。こうして、電極キャリアフィルム４５は、樹脂接合層４３が多数の共振器電極４４を既に担持している。
【００８６】
この大型の電極キャリアフィルム４５は、図５（ｃ）に示すように、第１の誘電体基板４２ａと、第２の誘電体基板４２ｂとの間に、挟み込んで、図５（ｄ）に図示の如く、両基板の外面から加圧下で加熱することにより誘電体基板４２と共振器電極４４および樹脂接合層４３を積層一体化する。図中Ｂ点で、積層した誘電体基板４６を、切断して、各誘電体共振器に分離する。
【００８７】
この実施形態では、切断分離した誘電体共振器各々の外表面に、外部電極４７を形成する。このような外部電極は、上述のように、電解めっき法、無電解めっき法、金属溶射法などにより形成することができる。
【００８８】
実施の形態６．
本発明の誘電体フィルタは、上記の実施形態に示した一対のストリップライン型の共振器電極と、第１の誘電体基板に埋設されて共振器電極の間を段間結合させる段間結合容量電極と、第２の誘電体基板に埋設されて共振器電極にそれぞれ容量結合した入力用及び出力用結合容量電極と、を備えている。
【００８９】
このような誘電体フィルタの断面構造を、図６（ｆ）に示すが、一対の誘電体基板が、一対の誘電体基板５４、５８との間に共振器電極５９ａ、５９ｂが配置され、樹脂接合層６０によって一対の誘電体基板５４、５８が接合されている。一方の誘電体基板５４の内部に段間結合容量電極５２が埋設され、段間結合容量電極５２が、２つの共振器電極５９ａ、５９ｂの両方の一端側と小容量で高周波結合ができるように配列されている。他方の誘電体基板５８には、二つの共振器電極５９ａ、５９ｂの一方と容量結合する入力側の容量結合電極５６ａが、また、共振器電極５９ａ、５９ｂの他方には容量結合する出力側容量結合電極５６ｂが、互いに離れて、埋設されている。
【００９０】
このような誘電体フィルタは、入力側の容量結合電極５６ａの高周波信号を両力することにより、一対の共振器電極間で形成されるフィルタ特性に従って、濾波されて信号が、出力側の容量結合電極５６ａから出力される。
【００９１】
誘電体フィルターの製造は、上記実施形態２ないし５に示す製造方法において示した誘電体基板を作る工程が容量結合電極の成形に使用される。特に、この工程には、セラミックの誘電体基板の内部に上記の共振器電極に容量結合するための結合電極を埋設する過程を含む。結合電極は、共振器電極に高周波信号を入力するための入力側の容量結合電極と、共振器電極からの高周波信号を出力するための出力用の容量結合電極を含む。さらに、共振器電極が２つ以上のストリップライン共振子である場合には、各ストリップライン間を電磁結合する段間結合用の電極を含む。
【００９２】
これらの結合用電極は、共振器電極を挟んでいる第１及び第２の誘電体基板の内部に配置されて、各共振器電極と容量結合するように小容量で対面して結合している。通常は、いずれかの誘電体基板に、段間用結合電極を埋設して、他方の誘電体基板に、入力用の結合電極を、出力用の結合電極と、それぞれ分離して、反対側に配置している。
【００９３】
以下に示す実施形態においては、第１の誘電体基板は、少なくとも２枚の高誘電率のセラミック板の１つの片面に、段間用結合電極５４を形成するための金属ペーストを印刷して、他方のセラミック板を上記金属ペーストを覆うようにグリーンシート同士合わせて、後に焼成し、電極埋設の一体の誘電体基板にする。
【００９４】
第２の誘電体基板についても同様に、一方の高誘電率セラミック板の片面に、入出力用容量結合電極を、金属ペーストで印刷し、他方の高誘電率セラミック板と同様に重ね合わせて焼成して、電極埋設の誘電体基板とする。
【００９５】
この金属ペーストは、融点の高い金属、例えば、白金、パラジウム、ニッケルその他を使用して、せラック板の高温焼成において、焼結して金属の上記結合電極が、安定して、誘電体基板に一体化される。
【００９６】
図６（ａ）には、１３５０℃程度の高温で焼結した極めて高いＱ値（具体的には、ｆＱ値が３，×１０^４から５×１０^４程度）を有する誘電体材料からなる複数のセラミックグリーンシートを積層して得た２枚のセラミック板５１ａ、５１ｂを用いる。セラミック板５１ｂの上面に、この例は、パラジウムを含む段間結合容量電極５２を印刷形成し、その上にセラミック板５１ａを配置して、図６（ｂ）のように、加圧して誘電体基板の焼成温度で焼結する。図６（ｃ）は、外面に外部電極５３を形成して、段間結合容量用の基板５４とする。
【００９７】
他方、同様な工程で、誘電体基板５５ａと５５ｂの内部にパラジウムよりなる入出力結合容量電極５６ａ、５６ｂを埋設した入出力結合容量基板５８を作る。
【００９８】
段間結合容量用の基板５４と入出力結合容量基板５８とは、図６（ｃ）に示すように、セラミックの外面に外部電極５３を形成する。さらに、入出力結合容量基板５８には、誘電体基板の焼成後、その端面に銀ペーストまたは銀溶射による入出力電極端子５７ａ、５７ｂを形成する。
【００９９】
図６（ｄ）には、図２に示す第２実施形態と同様の手順で、この例では、ＡｇメッキされたＣｕの金属箔を利用して、ストリップライン型の一対の共振器電極５９ａ、５９ｂを段間結合容量基板５４と入出力結合容量基板５８との間に配置して密着させたのち、図６（ｅ）の如く、基板間の間隙にエポキシ樹脂等の熱硬化性樹脂接着剤を注入充填する。これを所定の温度で加熱して、硬化させることにより、図６（ｆ）に示すような樹脂接合層６０によって誘電体基板と共振器電極が積層一体化された誘電体フィルタとする。
【０１００】
実施の形態７．
本発明の誘電体共振器ないし誘電体フィルタの共振器電極には、一対のストリップライン共振子を利用し、各共振子は一端を入出力用結合電極と結合されるが、他端側を開放端とし、開放端側を上記の一端側よりも広幅にすることが望ましい。
【０１０１】
このような構造の共振器電極を図７に示しているが、一対の誘電体基板６１内に配置された共振器電極６２ａ、６２ｂは、その開放端側に幅広部６２ａｗおよび６２ｂｗをそれぞれ備えている。一対の共振器に設けた幅広部は、電極間の相互に電磁結合するので、これを利用して、幅広部６２ａｗ、６２ｂｗの形状と相互間隔とを調節することにより、共振器間に生じる電磁界結合量を任意に制御してフィルターをその用途に応じた所望の特性に設定することができ、これによりフィルタ設計の自由度が向上する。
【０１０２】
上述の如く、誘電体基板は、上述のように、高い誘電率を有する上記のセラミック材料から高温焼結により形成されるが、好ましくは、表面の平滑度と平坦度とを高めることが、電極形成のために好ましい。上述のように、その平均表面粗さを、０．１μｍ〜２．０μｍの範囲とし、また誘電体基板の両端間の反りを１０μｍ以下とすることができる。これにより、特に、金属箔を利用する共振器電極と誘電体基板表面との接触頻度を高め、両者間の非接触空間の距離を極めて小さくすることができ、極めてＱ値の高い共振器を得ることができる。
【０１０３】
上記の実施形態で共振器電極として用いた金属箔に変えて、共振器電極材料として、例えば、銅粉若しくは銀粉又はこれらの混合粉と有機バインダーとを混合した導電性ペーストを用いて印刷形成することができる。
【０１０４】
また樹脂接合層の誘電率は誘電体基板の誘電率の１／４以下のものを用いることが好ましく、樹脂接合層に電界が入り込むことを回避することにより共振器のＱの低下を防止することができる。
【０１０５】
前記各実施の形態においては、誘電体基板の外表面に外部電極が形成されている一例を示したが、本願発明はこれに限ることなく、少なくとも外表面の一部に外部電極が形成されていればよい。
【０１０６】
高温焼成によって得られた高いｆＱ値（好ましくは、ｆＱ値が３×１０^４から５×１０^４程度）を備えた誘電体基板を使用し、必要かつ十分な厚さを有する共振器電極を樹脂または樹脂を主成分とする樹脂接合層によって誘電体基板と一体化しているために高いＱ値（シールド電極間距離２ｍｍの条件で、共振器Ｑが３００から３５０を有する）を備える誘電体共振器や低損失など優れたフィルタ特性を備える誘電体フィルタを得ることができる。
【０１０７】
実施の形態８．
本発明の誘電体フィルタは、特に、無線通信機とアンテナとの間に挿入して、使用することができる。例えば、アンテナと受信機の高周波増幅段と間に挿入して、信号波を妨害波から分離する受信用フィルタ装置として利用される。また、アンテナと送信機の電力増幅段との間に挿入して、送信機からの不要輻射を防止する送信用フィルタ層土地に利用できる。さらに、送信機用と受信機用に１つのアンテナを共用して、アンテナ−送信機間に１つのフィルタと、アンテナ−受信機間に別のフィルタを接続して、アンテナからの不要輻射波の低減と、妨害波の受信を低減して、混信を防止するにのにしようすることができる。
【０１０８】
図７には、セルラー無線電話システムにおける携帯電話の送信波と受信波とを分波する共用アンテナ用の送信用フィルタまたは受信用フィルタのブロック図を示している。
【０１０９】
この図７に示すようにアンテナに接続する整合回路の両端にそれぞれ本発明にの誘電体フィルタを配置することによって、送受共用アンテナに使用していた従来の占有空間の大きい同軸共振器に置き換えることができ、小型化されたアンテナ用フィルタ装置を得ることができる。
【０１１０】
さらに本発明の誘電体フィルタまたは上記アンテナ共用器を携帯電話等の通信機器に使用することにより、優れた特性を備え、且つ、小型化された通信機器を実現することが可能となる。
【０１１１】
【発明の効果】
本発明の製造方法により得られる誘電体共振器は、第１の誘電体基板と、該誘電体基板上に接触固定した共振器電極と、該共振器電極上に接触固定した第２の誘電体基板と、該第１と第２の誘電体基板の間で共振器電極の周囲に配置した樹脂接合層と、から構成するので、誘電体基板そのものを高いｆＱ値を有する高温焼結セラミック基板を利用することができ、共振器電極を二つの誘電体基板に直接接触するように接合して導体損失の少ない、Ｑ値の高い共振器とこれを利用したフィルタを提供することができる。
【０１１２】
誘電体基板には１ＧＨｚにおけるｆＱ値が３×１０^３〜１×１０^５の範囲にあるセラミックス誘電体を利用することができるので、Ｑ値の高い共振器とこれを利用したフィルタを提供することができる。
【０１１３】
誘電体基板の表面粗さを０．１μｍ〜２．０μｍの範囲とし、前記誘電体基板の表面の反り量が、該基板の両端間で、１０μｍ以下とすれば、共振器電極に金属箔を用いても、金属箔を誘電体基板に広い範囲で直接接触させ、これにより、導体損失を低減して、共振器及びフィルタのＱ値を高めることができる。
【０１１４】
本発明の誘電体共振器の製造方法は、金属箔より成る共振器電極を第１及び第２の誘電体基板のそれぞれの主面の間に挟持させ、共振器電極が介在して生じる２枚の誘電体基板の主面間に樹脂接着剤を充填し、接着剤を加熱硬化することにより樹脂接合層を形成するので、金属箔を誘電体基板に広い範囲で直接接触させ、これにより、導体損失を低減して、共振器及びフィルタのＱ値を高めた共振器とフィルタを製造することができる。
【０１１５】
本発明の誘電体共振器の製造方法は、共振器電極を形成すべき領域を除いて、樹脂接合層を構成するための接着剤をパターン印刷して、接着剤を半硬化させ、共振器電極を形成すべき領域に共振器電極とするための導電性ペーストを印刷充填し、第１の誘電体基板の共振器電極と第２の誘電体基板とを合わせて接着剤と導電性ペーストを完全硬化させて、樹脂接合層と共振器電極と誘電体基板とを一体化させるので、誘電体基板に導電性ペーストの共振電極が密着した共振器ととすることができ、高いいＱ値を具備した共振器及びフィルタが製造できる。
【０１１６】
本発明の誘電体共振器の製造方法は、接着剤フィルムに共振器電極の外形に刳りぬかれた刳り抜き部を有する接着剤フィルムを調製し、該刳り抜き部内に金属箔の共振電極を配置し、該接着剤フィルムを、第１及び第２の誘電体基板の間に配置すし、上記の２枚の誘電体基板の外面から加圧しながら加熱して接着剤フィルムを硬化させて樹脂接合層を形成し、誘電体基板と共振器電極とを樹脂接合層により一体化して積層体を形成するので、積層体を各個に切断して、各誘電体共振器を製造でき、とくに、接着剤フィルムに多数の共振器と固定してプリプレグ化しておけば、多数の共振器及びフィルタを量産的に製造することができる。
【図面の簡単な説明】
【図１】 本発明の実施の形態における誘電体共振器の分解斜視図（ａ）と、図１（ａ）に示した誘電体共振器の縦断面図（ｂ）を、示す。
【図２】本発明の実施の形態に係る誘電体共振器の製造方法を示す縦断面図（ａ〜ｆ）。
【図３】 本発明の別の実施形態における誘電体共振器の製造方法を示す縦断面図（ａ〜ｇ）。
【図４】 本発明の別の実施形態における誘電体共振器の製造方法を示す縦断面図（ａ〜ｇ）。
【図５】 本発明のさらに別の実施の形態における誘電体共振器の製造方法を示す縦断面図（ａ〜ｅ）。
【図６】 本発明のさらに別の実施形態における誘電体フィルタの製造方法を示す縦断面図（ａ〜ｆ）。
【図７】 本発明の別の実施形態における誘電体共振器の共振器電極の形状を示す横断面図。
【図８】 本発明の別の実施形態おけるフィルタを送受共用アンテナと送受信器との間に接続した無線通信機のブロック図。
【符号の説明】
２ 誘電体基板
３ 誘電体基板
４ａ 共振器電極
４ｂ 共振器電極
５ 樹脂接合層[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a dielectric resonator used mainly in high-frequency radio equipment such as a cellular phone, and a dielectric filter using the dielectric resonator, particularly a stripline type dielectric resonance that can use a high dielectric constant material having a high fQ value. vessel Manufacturing method About.
[0002]
[Prior art]
In recent years, many dielectric filters have been used as high-frequency filters for mobile phones, but there is a demand for further miniaturization and thinning, and they are used as bandpass filters or band rejection filters in the microwave region. Various types of microwave stripline filters are known. Stripline filter resonators are thin and suitable for surface mounting. Triplate laminated dielectric resonators using dielectric substrates include the above bandpass filters, voltage controlled oscillators, frequency synthesizers, etc. Widely used in
[0003]
These conventional dielectric resonators are formed by forming resonator electrodes such as Ag and Cu on a plurality of dielectric ceramic green sheets and then simultaneously firing them at a low temperature of about 900 ° C. at which these electrode materials do not melt. Joint integration of body substrates and internal resonator electrodes has been attempted.
[0004]
Further, a resonator having a structure in which a resonator electrode is sandwiched between dielectric substrates once sintered at a high temperature and welded with glass frit or the like has been reported.
[0005]
[Problems to be solved by the invention]
However, in the above-described conventional configuration, the dielectric material that requires simultaneous firing with the resonator electrode includes glass components such as glass frit and Bi. There were problems that the quality of crystals formed during the sintering was low, the dielectric constant was low, and a high Q value was difficult to obtain. Moreover, in the conventional dielectric resonators that have been co-fired and dielectric resonators in which a sintered dielectric substrate is welded with glass frit, cracks may occur in the dielectric substrate and glass frit depending on the thickness of the resonator electrode. There has been a problem that the characteristics are deteriorated or become unstable due to generation of glass or melted glass between the resonator electrode and the dielectric substrate.
[0006]
The present invention solves the above-described conventional problems, and uses a high-temperature sintered ceramic dielectric having a high Q value and a low resistivity conductor such as Ag or Cu having a sufficient thickness for the resonance portion. Enables low-loss dielectric resonators and dielectric filters that can be reduced in size and thickness Manufacturing method The purpose is to provide.
[0007]
[Means for Solving the Problems]
Of the present invention Obtained by manufacturing method The dielectric resonator is a resonator that is disposed between the first and second dielectric substrates and the dielectric substrate, and the resonator electrode is connected to the main surface of the pair of dielectric resonators. The resonator electrode is integrated into the dielectric substrate by being disposed in direct contact and adhering the dielectric substrate between the pair of dielectric substrates with a resin bonding layer surrounding the resonator electrode interposed therebetween. It is.
[0008]
That is, Dielectric resonator The structure includes a first dielectric substrate, a resonator electrode contacted and fixed on the first dielectric substrate, a second dielectric substrate fixed in contact with the resonator electrode, and the first dielectric substrate. And a resin bonding layer that is disposed around the resonator electrode and adheres to the dielectric substrate.
[0009]
The present invention Pertaining to In the resonator, since both surfaces of the resonator electrode are in direct contact with the dielectric substrate, the resonator electrode having a low resistance can be formed in close contact with the dielectric substrate having a high dielectric constant. A dielectric resonator having a value can be obtained. Such a dielectric resonator can be a dielectric filter having excellent filter characteristics. In particular, such a resonator uses a ceramic dielectric for the dielectric substrate, and a stripline type is applied to the resonator electrode, whereby a stripline filter having a high Q value can be obtained.
[0010]
The method for manufacturing a dielectric resonator according to the present invention includes a step of disposing a resonator electrode made of a metal foil between first and second dielectric substrates, and a resonator between main surfaces of the pair of dielectric substrates. A step of filling a resin adhesive in a gap generated by interposing an electrode, and a step of heating the dielectric substrate while applying pressure to cure the adhesive to form a resin bonding layer.
[0011]
This manufacturing method can obtain a dielectric resonator integrated with a bonding layer by directly contacting a resonator electrode with the principal surfaces of a pair of dielectric substrates by curing an adhesive, and has a high Q value. By using the body substrate, a dielectric resonator having excellent characteristics can be provided.
[0012]
Another method of manufacturing a dielectric resonator according to the present invention is an adhesive for forming a bonding layer on a main surface of a first dielectric substrate except for a region where a resonator electrode of a lower dielectric substrate is to be formed. Pattern-printing the agent and semi-curing the bonding layer made of the adhesive; printing and filling a conductive paste for forming the resonator electrode in a region where the resonator electrode is to be formed; After the main surface of the second dielectric substrate is aligned with the resonator electrode forming surface of the first dielectric substrate, the first and second dielectric substrates are heated and bonded while being pressed from the outer surface. A step of completely curing the agent and the conductive paste, and integrating the bonding layer, the resonator electrode, and the dielectric substrate;
There is something that consists of.
[0013]
As a dielectric substrate used in this manufacturing method, a dielectric having a high dielectric constant and a low dielectric loss by being sintered at a high temperature can be used. Since the resonator electrode formed from the conductive paste is bonded to the main surfaces of both dielectric substrates, a high resonator Q value can be realized.
[0014]
Another manufacturing method of the present invention is the step of preparing an adhesive film having a hollowed portion engraved in the outer shape of the resonator electrode on a resin film, and disposing a metal foil resonant electrode in the hollowed portion; The adhesive film is disposed between two dielectric substrates, and heated while applying pressure from the outer surfaces of the two dielectric substrates to cure the adhesive film to form a resin bonding layer. Forming a laminate by integrating the body substrate and the resonator electrode with a resin bonding layer.
[0015]
In particular, the adhesive film is preferably provided with a plurality or a plurality of the above-described hollow portions arranged, and resonator electrodes are arranged in each hollow portion, and the laminate is cut into individual pieces for each dielectric resonator. If the process is included, a plurality of or a large number of resonators can be made from a single laminate.
[0016]
In this manufacturing method, if a large-sized dielectric substrate that covers a large number of hollowed portions is prepared from an adhesive film, the prepreg having the above hollowed portions is prepared. There is an advantage that a resonator or a filter can be mass-produced.
[0017]
As the adhesive film, an adhesive resin film can be used. As another adhesive film, a mixed film obtained by mixing an adhesive resin and an inorganic filler can be used. The punched-out part is prepared in advance in a shape that can be fitted with a metal foil resonator electrode.
[0018]
In the above method for manufacturing a dielectric resonator, a dielectric substrate obtained by high-temperature sintering includes a step of pre-forming a dielectric substrate by firing a green sheet containing ceramic dielectric powder at a high temperature. An excellent resonator dielectric having a dielectric constant and low dielectric loss can be obtained. In particular, it is preferable to fire the laminate after laminating a plurality of dielectric ceramic green sheets.
[0019]
The present invention Pertaining to The resonator includes a single resonator electrode and can be used as a notch filter and as a voltage controlled oscillator. Furthermore, it includes a plurality of resonator electrodes arranged and can be used as a band-pass filter or a band elimination filter.
[0020]
The present invention includes such a dielectric filter. The dielectric filter includes a plurality of parallel resonator electrodes in a dielectric resonator, and is embedded in one of the dielectric substrates of the dielectric resonator. An interstage coupling capacitive electrode that can be electrostatically coupled to the resonator electrode, and a capacitive coupling electrode for input and output that is embedded in the other dielectric substrate and can be electrostatically coupled to each resonator electrode; The resonator electrodes are electromagnetically coupled to each other to form a filter. Thereby, a dielectric filter having excellent filter characteristics with low loss can be obtained.
[0021]
In order to manufacture the dielectric filter having such a structure according to the present invention, when the first dielectric substrate is formed, the interstage coupling capacitance electrode is formed by printing or the like between a plurality of laminated dielectric ceramic green sheets. When the second dielectric substrate is formed, the input / output coupling capacitance electrode is disposed between the plurality of laminated dielectric ceramic green sheets by printing or the like and then fired. Then, dielectric substrates are prepared, and these substrates are used as dielectric filters based on the method for manufacturing the dielectric resonator.
[0022]
In the dielectric filter thus manufactured, the resonator electrode is close to the interstage coupling electrode built in the first dielectric substrate, the resonator electrodes are electromagnetically coupled to each other, and the first The resonator electrode is disposed in the vicinity of the input / output coupling capacitance electrode incorporated in the dielectric substrate, and the resonator electrode is provided with an input terminal and an output terminal.
[0023]
The manufacturing method may include a step of forming an external electrode on at least a part of the outer surface of the dielectric substrate. In this case, the outer surface of the laminate is already covered with the outer electrode. Therefore, if it is cut, a resonator having external electrodes on the outer surface can be formed. However, in this manufacturing method, an external electrode is not formed in advance on the dielectric substrate, but a laminated body is formed by the above-described process, and the external electrode is formed on the outer surface of the dielectric resonator after being cut into individual pieces. May be formed.
[0024]
The present invention Pertaining to The dielectric filter can be used as a reception filter connected between the antenna and the high-frequency stage of the receiver, or as a transmission filter inserted between the antenna and the power amplification stage of the transmitter. . The antenna is used as a transmitter / receiver, and the dielectric filter is inserted as a receiving filter between the transmitting / receiving antenna and the receiver's high-frequency stage. At the same time, another dielectric filter is inserted between the shared antenna and the transmitter's power amplification stage. It can be used by inserting it as another transmission filter between. In this way, the dielectric filter can be used for a wireless communication device using a shared transmission / reception antenna.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
The dielectric filter of this embodiment includes a first dielectric substrate, a resonator electrode fixed on the substrate, a second dielectric substrate attached on the resonator electrode, and a pair of these dielectrics. A resin bonding layer formed around the resonator electrode between the body substrates, the bonding layer being bonded to the pair of dielectric substrates, and the resonator electrode being the pair of dielectric substrates It is held in direct contact with the main surface.
[0026]
In the present invention, the resonator electrode includes a stripline resonator. A resonator electrode having a single strip line disposed as a resonator between dielectric substrates can be used. Such a dielectric resonator can be used as a signal rejection filter in a specific frequency band. It can be used as a notch filter or a voltage controlled oscillator with a variable oscillation frequency. Further, the resonator electrode can be used as a filter in which two or more stripline type resonance elements can be arranged in parallel between the dielectric substrates, and the bandwidth is determined by electromagnetic coupling between the resonance elements. Such a dielectric resonator is used as a band pass filter and as a band elimination filter. In particular, the resonator electrode has a structure in which it is easy to use a pair of parallel stripline type resonance elements, and a filter having excellent characteristics can be formed. In the following embodiment, a dielectric-resonator in which a pair of parallel stripline type resonant elements are arranged and a filter using the dielectric-resonator will be exemplified.
[0027]
FIG. 1A, FIG. 1 and FIG. 1B show an example in which a pair of parallel strip lines are used for the resonator electrodes 4a and 4b, but the first dielectric substrate 2 and the first The resonator electrodes 4a and 4b fixed in direct contact with the surface of the dielectric substrate, the second ceramic dielectric substrate 3 fixed in contact with the resonator electrodes 4a and 4b, and the pair of dielectrics A resin bonding layer 5 is formed between the substrates 2 and 3 and fills the periphery of the resonator electrodes 4a and 4b to bond the pair of dielectric substrates 2 and 3 together. In this example, the external electrode 1 covers the outer surfaces of the first and second dielectric substrates and is used as a high-frequency shield.
[0028]
Conventionally, although a material having excellent conductivity including copper Cu or silver Ag is used for the resonator electrode, a sufficiently high Q is obtained when the resonator electrode material and the dielectric substrate are simultaneously fired. Although the values were not obtained, the present invention performs the high-temperature firing of the dielectric substrate and the assembly of the dielectric resonator including the bonding of the substrate and the electrode by the resin bonding layer in separate steps. The high-Q sintered dielectric with high Q value can be joined and integrated with the resonator electrode and the resin adhesive layer as it is, without deteriorating the properties of the high-temperature fired ceramic dielectric, and with high conductivity of the metal electrode Can be used to exhibit excellent characteristics as a resonator. The resonator having such a configuration is provided as a small dielectric filter.
[0029]
In the present invention, the dielectric substrate is made of a ferroelectric ceramic, and the ceramic substrate includes a glass substrate. In particular, the invention provides that the fQ value of the ceramic material constituting the dielectric substrate is 3 × 10 3 at 1 GHz. ³ It is preferable to use a material in the above range.
[0030]
The fQ value of the substrate material is 3 × 10 ³ If it is lower, a sufficiently high Q value cannot be obtained as a dielectric resonator, and sufficient characteristics as a filter cannot be obtained. This is a characteristic that can be realized with a normal glass ceramic substrate, and is a property that is low enough to be obtained by a resonator made of a glass ceramic substrate co-fired with silver Ag or copper Cu. On the other hand, fQ is 1 × 10 ⁵ It is difficult to realize a ceramic with a dielectric constant of 30 or more.
[0031]
High dielectric constant materials include Ba-Ti-O, Ba-Nd-Ti-O, Ba-Sm-Ti-O, Bi-Nb-O, Zr-Ti-Mg-Nb-O, etc. These oxide ceramics can be used. These dielectrics are sintered in advance at a sufficiently high temperature to be a ceramic having a high dielectric constant and a low dielectric loss, and are used for resonators and filters.
[0032]
As the dielectric material, a low-sinterable substrate such as a glass ceramic substrate having a slightly high fQ value or a Ba-Ca-Nb-O-based oxide ceramic substrate can be used, and similarly, a high Q resonator characteristic is obtained. I was able to.
[0033]
The resonator electrode is formed between a pair of dielectric substrates from a metal foil or a conductive paste, as described below, in particular, forming a strip line, and such a resonator electrode is formed of two or more strips. Lines are arranged in parallel so that adjacent strip lines can be electromagnetically coupled to each other.
[0034]
When the dielectric resonator is used as a filter, an input electrode is coupled to one end of one strip line and an output electrode is coupled to one end of the other strip line with a small capacity. An electrode for interstage capacitive coupling is disposed on the one end side of both strip lines. Such a coupling electrode is embedded and held in a dielectric substrate. In particular, it is desirable that the resonator electrode is provided with a wide portion in which the other end side of the resonator strip line is an open end and the open end side is wider than the one end side.
[0035]
The metal foil includes a foil of a metal material mainly composed of copper Cu or silver Ag. As such a resonant electrode, a copper foil, a silver foil, or a copper foil having silver plated on the surface can be used. These materials are preferable because of their low resistivity.
[0036]
As the resonator electrode, a conductive resin layer containing conductive particles can be used. As such conductive particles, a metal powder mainly composed of copper Cu or silver Ag can be used. Such powder is preferably silver powder or copper powder. For example, an epoxy resin is used as the resin or binder forming the paste. The conductive resin layer is obtained by applying a paste on a substrate and curing the binder.
[0037]
Using conductive paste for the resonator electrode increases the conductor resistance as an electrode compared to the metal foil, but the electrode can reliably adhere to the dielectric substrate due to the presence of the adhesive resin component. The high fQ of the body substrate can be used effectively, and as a result, stable resonator characteristics can be obtained.
[0038]
It is preferable that the dielectric substrate has high flatness and high smoothness in the surface area of the main surface where the resonator electrode faces. In particular, when the resonator electrode is a metal foil, the surface roughness of the dielectric substrate is preferably 2.0 μm or less. When the surface roughness exceeds 2.0 μm, the conductor resistance of the metal foil increases, which is not preferable. In order to provide such flatness and smoothness, the sintered ceramic substrate is precisely polished. In general, it is possible to make the surface roughness 0.1 μm or less, but it takes time for the polishing process and causes an increase in cost, so the range of 0.1 μm to 2.0 μm is preferable.
[0039]
In particular, when the resonator electrode is a metal foil, the dielectric substrate preferably has a surface warpage between both ends of the resonator of 10 μm or less as the flatness of the main surface on which the resonance electrode is disposed. If the warp is 10 μm or more at the shape level of the resonator, a gap corresponding to the amount of warp is formed between the metal foil and the dielectric substrate, so that the Q value of the dielectric resonator is lowered, which is not preferable.
[0040]
As a result, it is possible to prevent a resin bonding layer or the like from interposing between the resonator electrode and the dielectric substrate, and to directly contact the resonator electrode and the dielectric substrate to prevent the Q value from being lowered. it can.
[0041]
Furthermore, the thickness of the resonator electrode 4 is preferably 50 μm or more in order to reduce insertion loss as a dielectric filter. On the other hand, if the resonator electrode has a thickness of 400 μm or more, the thickness of the resonator itself becomes too large, and it becomes difficult to reduce the thickness of the resonator although it has a high Q. Therefore, the thickness of the resonator electrode is preferably in the range of 50 to 400 μm.
[0042]
The resin bonding layer is filled between a pair of dielectric substrates sandwiching the resonator electrode to bond the two substrates. The resin bonding layer is made of an adhesive made of a thermosetting or thermoplastic resin. Used. At the time of bonding, although the resonator is heated to a low temperature necessary for curing the adhesive, it is not necessary to heat the resonator to a particularly high temperature, so that the resonator characteristics are not deteriorated. An epoxy resin can be used for such an adhesive layer.
[0043]
The adhesive forming the resin bonding layer can further include a composite material in which a thermosetting resin and an inorganic filler are mixed. The mixing of the inorganic filler has a function of adjusting the thermal expansion coefficient of the resin bonding layer to be close to the expansion coefficient of the dielectric substrate and stabilizing the bonding between the substrates.
[0044]
It is preferable that the resin bonding layer has a dielectric constant lower than that of the dielectric substrate because the high-frequency loss between the resonator electrodes can be kept low. In particular, it is preferable that the dielectric constant of the resin bonding layer be 1/4 or less that of the dielectric substrate. Also from this point, epoxy resin is preferable as the resin constituting the resin bonding layer.
[0045]
Embodiment 2. FIG.
This embodiment provides a method for manufacturing a dielectric resonator. In this manufacturing method, each of the first and second dielectric substrates is used by using a resonator electrode made of a metal foil. A step of sandwiching between the main surfaces, a step of filling a resin adhesive between the main surfaces of the two dielectric substrates generated by interposing the resonator electrodes, and a resin bonding layer by heating and curing the adhesive Forming.
The dielectric substrate used here is prepared in advance from a ferroelectric ceramic by high-temperature sintering, and has a high dielectric constant and a low dielectric loss. Such a ceramic substrate is manufactured by forming a green sheet from a mixture powder of oxide fine powder and an appropriate binder into one layer or multiple layers, degreasing, and sintering at a sufficiently high temperature. The ceramic substrate can also be made by a method in which oxide powder is dry-molded into a sheet-like green compact and the sheet is sintered at a high temperature.
[0046]
In this embodiment, in FIGS. 2 (a) and 2 (b), a ceramic green sheet 11 is made from a slurry obtained by kneading a dielectric oxide powder and an organic binder, and a desired number of green sheets are laminated, After degreasing and pre-baking, the dielectric substrate 12 is obtained by sintering at a high temperature.
[0047]
An external electrode can be previously deposited on the sintered substrate. FIG. 2 (c) shows an external electrode formation step, except that the electrode formation portion on the main surface of the dielectric substrate is formed to form an external electrode by forming a metal film such as silver Ag or copper Cu. The external electrode 13 is formed by applying a metal paste and performing a baking process. Another method can also form a metal film by metal plating or metal spraying. However, the external electrode step may be omitted, and the external electrode may be provided on the outer surface of the dielectric substrate of the manufactured filter without a dielectric resonator.
[0048]
In the step of forming the resonance electrode, the main surfaces of the first and second dielectric substrates sandwich the resonator electrode and place the resonator electrode at a predetermined position. A pair of resonator electrodes is arranged on the main surface of one dielectric substrate in a predetermined arrangement relationship, and the main surface of the other dielectric substrate is brought into contact with the resonator electrode, and the pair of dielectric electrodes A resin adhesive is filled in the gaps between the substrates and cured to form a resin bonding layer.
[0049]
In FIG. 2 (d), the main surfaces of the first and second dielectric substrates are opposed to each other, and a pair of parallel strip lines as the resonator electrodes 15a and 15b are arranged between the metal foils. Are adhered to the main surfaces of the pair of dielectric substrates 12a and 12b. Thereafter, as shown in FIG. 2E, the gap between the two dielectric substrates 12a and 12b is filled with a resin adhesive, in this example, an epoxy-based thermosetting resin. Next, the adhesive is cured by heating to the resin curing temperature while pressing between the dielectric substrates.
[0050]
After the adhesive is cured, as shown in FIG. 2 (f), the dielectric substrates 12a and 12b are bonded by the resin bonding layer 16, and the resonator electrodes 15a and 15b are integrated between the substrates 12a and 12b. A dielectric resonator is obtained.
[0051]
In this manufacturing method, the epoxy resin adhesive is applied to the gap between the dielectric substrates in a state where the resonator electrodes 15a and 15b are pressed from both surfaces of the dielectric substrates 12a and 12b and are in close contact with the main surfaces of these substrates. It is possible to inject, and it is possible to strongly bond the adhesive electrode between the resonator electrode and the dielectric substrate without intervening an adhesive.
[0052]
In the present invention, as seen in this embodiment, a ceramic substrate that has been sintered at a high temperature in advance is used. ⁴ A dielectric substrate having a high dielectric fQ value can be used. (In the conventional method, ceramic firing is insufficient, and the limit fQ value of the ceramic substrate is 3 × 10. ³ ~ 4x10 ³ This is a high temperature sintering, and a metal foil strip line having a considerable thickness of about 50 to 400 μm is disposed between the ceramic substrates after being sintered at high temperature. A resonator (having a shield-to-shield distance of 2 mm) having a Q value of about 250 can be improved to about 320 to 350. Therefore, the insertion loss can be reduced by using this dielectric resonator for a filter.
[0053]
[Example 1]
In this example, according to this embodiment, a dielectric resonator was manufactured and the resonator characteristics were examined. In FIG. 2, in this embodiment, a dielectric substrate is mixed with a Zr—Ti—Mg—Nb—O-based oxide ceramic powder and an acrylic binder to form a slurry, and a ceramic green sheet 11 formed from the slurry is formed. A predetermined number of sheets were laminated and fired at 1350 ° C. at a high temperature to form a ceramic dielectric substrate 12 having a thickness of 1 mm. In this example, a conductive paste mainly composed of Ag was applied, leaving a predetermined surface of the dielectric substrate, and baked at 850 ° C. to form the external electrode 13.
[0054]
Next, between these two dielectric substrates 12a and 12b, strip line resonator electrodes 15a and 15b having a thickness of 100 μm and a width of 1 mm arranged in parallel using copper foil are arranged, and the dielectric substrates 12a and 12b are arranged. Was brought into close contact with the resonator electrode. After the adhesion, as shown in FIG. 2 (e), an epoxy resin adhesive was filled in the gap between the two dielectric substrates 12a and 12b, and was cured by heating to produce a dielectric resonator sample A.
[0055]
As a comparative example, the resonator electrodes 15a and 15b were placed on the dielectric substrates 12a and 12b and then pressed from both sides of the substrate, as in the above example, but the substrate-electrode was not intentionally adhered. A gap between the substrate and the electrode was provided, and an adhesive such as an epoxy resin was injected between the dielectric substrates and cured. Thus, samples B and C in which an adhesive was interposed between the resonator electrode and the dielectric substrate were produced in the same manner.
[0056]
[Table 1]

[0057]
These samples A to C were used for testing. The test results are shown in Table 1. From the data shown in Table 1, it can be seen that the Q value is drastically lowered when the adhesive layer penetrates even a little in the gap between the resonator electrode and the dielectric substrate. This indicates that the resonator electrode and the dielectric substrate must be in direct contact with the high-Q resonator.
[0058]
Embodiment 3. FIG.
The method for manufacturing a dielectric resonator according to the present invention includes a method in which a conductive paste is applied on a dielectric substrate to form a resonator electrode. In this manufacturing method, as shown in the second embodiment, a dielectric substrate in which a plurality of ceramic green sheets are laminated and the laminated plate is formed by high-temperature sintering is used.
[0059]
In this embodiment, in order to apply the conductive paste for the resonator electrode on the dielectric substrate, the resonator electrode on the dielectric substrate should be formed on the main surface of the first dielectric substrate. A step of pattern-printing a resin adhesive for constituting the resin bonding layer except for the region and semi-curing the adhesive layer is included. Next, a step of applying a conductive paste for forming a resonator electrode to the region where the resonator electrode is to be formed on the main surface of the substrate, using the adhesive layer as a mask.
[0060]
Further, the first dielectric substrate is aligned with the main surface of the second dielectric substrate facing the surface on which the resonator electrode of the first dielectric substrate is formed, and then the first and second dielectric substrates are moved from the outer surface. The method includes a step of heating while applying pressure to completely cure the semi-cured resin bonding layer and the conductive paste, thereby integrating the resin bonding layer, the resonator electrode, and the dielectric substrate.
[0061]
3 (a) and 3 (b), similar to FIGS. 2 (a) and 2 (b) shown in the above embodiment, a plurality of ferroelectric ceramic green sheets 11 are laminated and fired. A dielectric substrate 12 is formed. In this embodiment, in FIG. 3C, the dielectric substrate has external electrodes 23 formed on the other surfaces except for the electrode formation surface.
[0062]
In the step of forming the adhesive pattern in FIG. 3D, a resin adhesive is selectively printed on the upper surface of the first dielectric substrate to form an adhesive pattern, which is preliminarily heated. The resin bonding layer 24 is set to a B-stage semi-cured state.
[0063]
In FIG. 3E, the conductive paste 25 containing metal powder is printed and filled with the squeegee 26 or the like on the patterned resin bonding layer on the first dielectric substrate 22b. The second dielectric substrate 22a is disposed on the first dielectric substrate 22b.
[0064]
As shown in FIG. 3G, by pressing and heating from both sides to cure the semi-cured resin bonding layer 24 and the conductive paste 25, as shown in FIG. A dielectric resonator having an integral structure in which the two dielectric substrates 22 a and 22 b sandwich the resonator electrodes 27 a and 27 b and are joined by the resin joining layer 24 is obtained.
[0065]
As described above, a metal paste obtained by kneading a metal powder and a thermosetting resin binder is used as the conductive paste. This metal paste is bonded to the dielectric substrate simultaneously with the formation of the resonator electrode. You can also As described above, silver or copper powder is used for the metal. As another conductive paste, a thermally decomposable metal organic material (for example, metal alkoxide (Me-O-R)) was applied on the first dielectric substrate masked by the above adhesive layer. Then, it can be thermally decomposed by heating (MOD method) to deposit a metal in the pattern to form a resonator electrode.
[0066]
[Example 2]
Next, a dielectric resonator according to the manufacturing method of this embodiment was manufactured. 3A and 3B, a plurality of Ba—Nd—Ti—O-based ceramic green sheets 11 are laminated and fired at 1350 ° C., and a sintered ceramic substrate 12 is obtained. Except for the main surface for forming the resonator electrode, the first and second dielectric substrates were baked with Ag paste on all surfaces to form external electrodes 23.
[0067]
On the first substrate, an epoxy resin adhesive is applied on the main surface by pattern printing on the main surface, leaving the shape of the strip line as the resonator electrode, and heated to apply the resin bonding layer 24 to the first substrate. The stage was in a semi-cured state. A resonator electrode is disposed on a surface area of the first dielectric substrate that is not covered by the patterned resin bonding layer 24 by inserting a silver foil cut into an electrode shape, The second dielectric substrate 22a was placed on the substrate 22b, and the resin paste was melted and cured by heating at 150 ° C. while applying pressure of 3 MPa to both outer surfaces of the two substrates. Thereby, the dielectric resonator joined integrally by the resin joining layer 24 was made.
[0068]
The comparative example uses a similar sintered dielectric substrate onto which the external electrode 23 is baked, and selectively prints and applies glass paste as an adhesive on the main surface of the first dielectric substrate. A patterned bonding layer 24 was formed. In the same manner as in the above embodiment, an Ag metal foil is fitted on the upper surface of the substrate that is not covered with the bonding layer 24, and the second dielectric substrate 22a is formed on the first dielectric substrate 22b. I put it. In this comparative example, while pressurizing at 3 MPa from both sides, since this example is a glass paste, it was heated to 600 ° C. to melt and bond the glass. Thus, dielectric substrates 22a and 22b facing each other, resonator electrodes 27a and 27b, and a dielectric resonator bonded by the glass bonding layer 24 were produced. Below, the test result of an Example and a comparative example is shown.
[0069]
[Table 2]

[0070]
As shown in Table 2, in the resonator structure according to the laminate of this embodiment, the resin adhesive as the resin bonding layer has a low bonding work temperature and a low elastic modulus. It can be seen that the dielectric substrate can be directly joined, and the resonator exhibits a high Q value.
[0071]
On the other hand, in the comparative example, by applying a glass adhesive layer, the dielectric substrates are welded together, and the dielectric substrate having a high Q and the resonator electrode having high conductivity are directly joined. However, in practice, the Q characteristic is deteriorated. In the comparative example, the molten glass flowed between the dielectric substrate and the resonator electrode, and a crack was generated around the end of the electrode. Cracks are caused by the difference in coefficient of thermal expansion between the glass and the ceramic dielectric.
[0072]
Embodiment 4 FIG.
In the production method of the present invention, a metal foil to be used as a resonator electrode and a semi-cured adhesive film provided with a hollow portion that supports the outer shape of the metal foil, as an electrode carrier film, prepreg, It includes a method in which the pre-flag is sandwiched between a pair of dielectric substrates and integrated by heating under pressure. The manufacturing method includes a step of providing a punched portion that is hollowed out in the outer shape of the resonator electrode in the adhesive film, disposing a metal foil resonant electrode in the punched-out portion, A step of placing between the second dielectric substrates and heating while applying pressure from the outer surfaces of the two dielectric substrates to cure the adhesive film to form a resin bonding layer and resonate with the dielectric substrates. Forming a laminate by integrating the electrode with the resin bonding layer.
[0073]
A large number of punched portions are arranged in the above adhesive film, resonator electrodes are arranged in each punched portion, and after the step of forming the laminate, the laminate is cut and separated into dielectric resonators. A process is adopted.
[0074]
In this embodiment, in particular, a large number of resonator electrodes are arranged in advance on a prepreg, and each resonator electrode is sandwiched and integrated by a pair of upper and lower dielectric substrates, and then a resonance to be a dielectric resonator later. A large number of dielectric resonators can be made by cutting and dividing the electrode carrier film in units of unit electrodes.
[0075]
4A to 4C, similarly to the above-described embodiment, a process of forming the first and second dielectric substrates 12a and 12b by laminating and firing a plurality of ceramic green sheets 11 is performed. Show. Also in this example, the external electrode is formed in advance on the outer surface of the substrate.
[0076]
FIG. 4D shows a process for preparing an electrode carrier film from an adhesive film. The shape of a resonator electrode, in this example, a strip line, is applied to a thermosetting resin film 31 in a semi-cured state. A plurality of hollow portions having a slightly larger shape, that is, a plurality of openings 32 are provided, and strip lines 33a and 33b are respectively inserted into the openings 32 as indicated by arrows to form an electrode carrier film 34. create. The electrode carrier film 34 integrally includes the resonator electrode 33 and the resin bonding layer 31.
[0077]
Next, as shown in FIG. 4 (e), the first dielectric substrate 12b and the second dielectric substrate 12a made in the steps of FIGS. Then, the resonator electrodes carried on the electrode carrier film 34 are sandwiched and held, and heated while applying pressure to both surfaces of the substrate to cure the adhesive film. Thereby, the dielectric substrate, the resonator electrode and the resin bonding layer are laminated and integrated.
[0078]
In this embodiment, a pair of opposing dielectric substrates are used as a set of dielectric substrates, and each set of dielectric substrates is separated from each other. Therefore, as shown in FIG. 4 (f), the adhesive film between adjacent dielectric substrates is cut (at the point B in the figure), and the dielectric resonator shown in FIG. obtain.
[0079]
In this embodiment, the resin bonding layer 31 protrudes from both side surfaces of the dielectric substrate 12, but the cutting point in FIG. 4F is changed so that the cutting portion of the resin bonding layer 31 is the dielectric substrate. It can also cut | disconnect so that it may become flush with the end surface of.
[0080]
For the adhesive film 31 in a semi-cured state for the resin bonding layer, a thermosetting resin that itself has adhesiveness by heating is used, and for example, an epoxy resin can be used. Further, as described above, an inorganic powder such as a fine silica powder may be added to the adhesive film as a filler to a thermosetting resin such as an epoxy resin.
[0081]
As the resin bonding layer used for the electrode carrier film 34, a non-adhesive resin film can also be used. In this case, a dielectric substrate is obtained by thinly applying an epoxy adhesive having excellent adhesion to the surface of the film. Glue together. As such a non-adhesive resin film, a resin film having a particularly small dielectric loss tangent such as a polyester resin or a fluororesin (for example, polytetrafluoroethylene) and having excellent dielectric characteristics may be used. Such a resin bonding layer is advantageous because the Q value hardly decreases even when an electric field enters.
[0082]
As a feature of this embodiment, since an opening for arranging the resonator electrode is provided in the film-like resin bonding layer, the shape of the opening is made larger than the shape of the resonator electrode, and the resin bonding is performed. There is an advantage that an arbitrary gap can be formed between the layer and the resonator electrode, and the influence of the dielectric property of the resin bonding layer around the resonator electrode can be reduced.
[0083]
Embodiment 5 FIG.
This embodiment uses an electrode carrier film similar to the previous embodiment, but this embodiment is large enough to cover the first and second dielectric substrates to cover a number of resonant electrodes. The outer shape is used for mass production of dielectric resonators or filters.
[0084]
As shown in FIGS. 5 (a) and 5 (b), a plurality of dielectric ceramic green sheets 41 are laminated and then fired at a high temperature so that the dielectric characteristics are excellent and sufficiently larger than the dimensions of the resonator electrodes. First and second dielectric substrates 42a and 42b are formed.
[0085]
In FIG. 5 (c), hollow portions, that is, openings are arranged in a large thermosetting resin film 43 such as an epoxy resin in a semi-cured state, and a pair of stripline resonator electrodes 44a and 44b are opened. The electrode carrier film 45 is made by fitting into the part. Thus, in the electrode carrier film 45, the resin bonding layer 43 already carries a large number of resonator electrodes 44.
[0086]
As shown in FIG. 5C, the large electrode carrier film 45 is sandwiched between the first dielectric substrate 42a and the second dielectric substrate 42b, and is illustrated in FIG. 5D. As described above, the dielectric substrate 42, the resonator electrode 44, and the resin bonding layer 43 are laminated and integrated by heating under pressure from the outer surfaces of both substrates. At the point B in the figure, the laminated dielectric substrate 46 is cut and separated into dielectric resonators.
[0087]
In this embodiment, an external electrode 47 is formed on the outer surface of each cut and separated dielectric resonator. As described above, such an external electrode can be formed by an electrolytic plating method, an electroless plating method, a metal spraying method, or the like.
[0088]
Embodiment 6 FIG.
The dielectric filter of the present invention includes a pair of stripline resonator electrodes shown in the above embodiment and an interstage coupling capacitor embedded between the resonator electrodes and interstage coupled between the resonator electrodes. And an input and output coupling capacitive electrode embedded in a second dielectric substrate and capacitively coupled to the resonator electrode.
[0089]
A sectional structure of such a dielectric filter is shown in FIG. 6 (f). A pair of dielectric substrates is provided with resonator electrodes 59a and 59b disposed between the pair of dielectric substrates 54 and 58, and resin. A pair of dielectric substrates 54 and 58 are bonded by the bonding layer 60. An interstage coupling capacitive electrode 52 is embedded in one dielectric substrate 54 so that the interstage coupling capacitive electrode 52 can perform high-frequency coupling with one end of both of the two resonator electrodes 59a and 59b with a small capacity. It is arranged. The other dielectric substrate 58 has an input-side capacitive coupling electrode 56a capacitively coupled to one of the two resonator electrodes 59a and 59b, and an output-side capacitance capacitively coupled to the other of the resonator electrodes 59a and 59b. The coupling electrodes 56b are embedded away from each other.
[0090]
Such a dielectric filter filters both the high frequency signal of the capacitive coupling electrode 56a on the input side according to the filter characteristic formed between the pair of resonator electrodes and the capacitive coupling on the output side. Output from the electrode 56a.
[0091]
In the production of the dielectric filter, the process for producing the dielectric substrate shown in the production methods shown in the above-described embodiments 2 to 5 is used for forming the capacitive coupling electrode. In particular, this step includes a process of embedding a coupling electrode for capacitive coupling to the resonator electrode inside a ceramic dielectric substrate. The coupling electrode includes an input side capacitive coupling electrode for inputting a high frequency signal to the resonator electrode and an output capacitive coupling electrode for outputting a high frequency signal from the resonator electrode. Further, when the resonator electrode is two or more stripline resonators, an interstage coupling electrode for electromagnetically coupling the striplines is included.
[0092]
These coupling electrodes are arranged inside the first and second dielectric substrates sandwiching the resonator electrode, and are coupled to face each other with a small capacity so as to be capacitively coupled to each resonator electrode. . Usually, an interstage coupling electrode is embedded in one of the dielectric substrates, and the input coupling electrode is separated from the output coupling electrode on the other dielectric substrate. It is arranged.
[0093]
In the embodiment shown below, the first dielectric substrate is printed with a metal paste for forming the interstage coupling electrode 54 on one side of at least two high dielectric constant ceramic plates, The other ceramic plate is put together with the green sheet so as to cover the metal paste, and then fired to form an integrated dielectric substrate with an electrode embedded therein.
[0094]
Similarly, for the second dielectric substrate, an input / output capacitive coupling electrode is printed on one surface of one high dielectric constant ceramic plate with a metal paste, and is stacked and fired in the same manner as the other high dielectric constant ceramic plate. Thus, an electrode-embedded dielectric substrate is obtained.
[0095]
This metal paste uses a metal having a high melting point, such as platinum, palladium, nickel, etc., and sinters the high-temperature firing of the rack plate so that the above-mentioned bonded electrode of the metal is stably formed on the dielectric substrate. Integrated.
[0096]
FIG. 6A shows an extremely high Q value sintered at a high temperature of about 1350 ° C. (specifically, the fQ value is 3 × 10 ⁴ To 5 × 10 ⁴ Two ceramic plates 51a and 51b obtained by laminating a plurality of ceramic green sheets made of a dielectric material having a degree) are used. In this example, an interstage coupling capacitive electrode 52 containing palladium is printed and formed on the upper surface of the ceramic plate 51b, and the ceramic plate 51a is disposed on the ceramic plate 51b. Then, as shown in FIG. Sintering is performed at the firing temperature of the substrate. In FIG. 6C, an external electrode 53 is formed on the outer surface to form a substrate 54 for interstage coupling capacitance.
[0097]
On the other hand, in the same process, an input / output coupling capacitance substrate 58 is produced in which input / output coupling capacitance electrodes 56a and 56b made of palladium are embedded in the dielectric substrates 55a and 55b.
[0098]
As shown in FIG. 6C, the interstage coupling capacitance substrate 54 and the input / output coupling capacitance substrate 58 form an external electrode 53 on the outer surface of the ceramic. Further, on the input / output coupling capacitor substrate 58, after firing the dielectric substrate, input / output electrode terminals 57a and 57b are formed on the end face thereof by silver paste or silver spraying.
[0099]
FIG. 6D shows a procedure similar to that of the second embodiment shown in FIG. 2 and, in this example, a pair of stripline resonator electrodes 59a using Ag-plated Cu metal foil, 59b is disposed between the interstage coupling capacitor substrate 54 and the input / output coupling capacitor substrate 58 and brought into close contact therewith, and then, as shown in FIG. 6E, a thermosetting resin adhesive such as an epoxy resin is provided in the gap between the substrates. Inject filling. This is heated at a predetermined temperature and cured to obtain a dielectric filter in which the dielectric substrate and the resonator electrode are laminated and integrated by the resin bonding layer 60 as shown in FIG.
[0100]
Embodiment 7 FIG.
A pair of stripline resonators is used for the resonator electrodes of the dielectric resonator or dielectric filter of the present invention, and each resonator has one end coupled to the input / output coupling electrode, but the other end is open. It is desirable that the open end side is wider than the one end side.
[0101]
Although the resonator electrode having such a structure is shown in FIG. 7, the resonator electrodes 62a and 62b arranged in the pair of dielectric substrates 61 are provided with wide portions 62aw and 62bw on the open end sides, respectively. Yes. Since the wide portions provided in the pair of resonators are electromagnetically coupled to each other between the electrodes, electromagnetic waves generated between the resonators are adjusted by adjusting the shapes and the mutual intervals of the wide portions 62aw and 62bw. The amount of field coupling can be arbitrarily controlled, and the filter can be set to a desired characteristic according to its use, thereby improving the degree of freedom in filter design.
[0102]
As described above, the dielectric substrate is formed by high-temperature sintering from the above ceramic material having a high dielectric constant, as described above. Preferably, the surface smoothness and flatness are improved by increasing the electrode. Preferred for formation. As described above, the average surface roughness can be in the range of 0.1 μm to 2.0 μm, and the warpage between both ends of the dielectric substrate can be 10 μm or less. Thereby, in particular, the contact frequency between the resonator electrode using the metal foil and the surface of the dielectric substrate can be increased, the distance of the non-contact space between them can be extremely reduced, and a resonator having an extremely high Q value can be obtained. be able to.
[0103]
Instead of the metal foil used as the resonator electrode in the above embodiment, as the resonator electrode material, for example, copper powder, silver powder, or a conductive paste obtained by mixing these mixed powders and an organic binder is used for printing. be able to.
[0104]
The dielectric constant of the resin bonding layer is preferably less than ¼ of the dielectric constant of the dielectric substrate, and it is possible to prevent the resonator from lowering by avoiding the electric field from entering the resin bonding layer. Can do.
[0105]
In each of the above embodiments, an example is shown in which the external electrode is formed on the outer surface of the dielectric substrate. However, the present invention is not limited to this, and the external electrode is formed on at least a part of the outer surface. Just do it.
[0106]
High fQ value obtained by high temperature firing (preferably fQ value of 3 × 10 ⁴ To 5 × 10 ⁴ And a resonator electrode having a necessary and sufficient thickness is integrated with the dielectric substrate by a resin or a resin bonding layer containing resin as a main component. A dielectric resonator having an excellent filter characteristic such as a low-loss or a dielectric resonator having a resonator Q of 300 to 350 on the condition that the distance between shield electrodes is 2 mm can be obtained.
[0107]
Embodiment 8 FIG.
In particular, the dielectric filter of the present invention can be used by being inserted between a radio communication device and an antenna. For example, it is used as a reception filter device that is inserted between an antenna and a high-frequency amplification stage of a receiver to separate a signal wave from an interference wave. Also, it can be used as a transmission filter layer land that is inserted between the antenna and the power amplification stage of the transmitter to prevent unwanted radiation from the transmitter. Furthermore, by sharing one antenna for the transmitter and the receiver, one filter is connected between the antenna and the transmitter, and another filter is connected between the antenna and the receiver. It can be used to reduce and reduce interference reception and prevent interference.
[0108]
FIG. 7 shows a block diagram of a transmission filter or a reception filter for a shared antenna that demultiplexes a transmission wave and a reception wave of a cellular phone in a cellular radiotelephone system.
[0109]
As shown in FIG. 7, the dielectric filters according to the present invention are arranged at both ends of the matching circuit connected to the antenna, thereby replacing the conventional coaxial resonator having a large occupied space used for the transmission / reception antenna. Therefore, a miniaturized antenna filter device can be obtained.
[0110]
Furthermore, by using the dielectric filter of the present invention or the antenna duplexer in a communication device such as a mobile phone, it is possible to realize a communication device having excellent characteristics and reduced in size.
[0111]
【The invention's effect】
Of the present invention Obtained by manufacturing method The dielectric resonator includes a first dielectric substrate, a resonator electrode fixed in contact with the dielectric substrate, a second dielectric substrate fixed in contact with the resonator electrode, the first and first dielectric substrates. And a resin bonding layer disposed around the resonator electrode between the two dielectric substrates, so that the dielectric substrate itself can use a high-temperature sintered ceramic substrate having a high fQ value. It is possible to provide a resonator having a low Q and a high Q value by joining electrodes so as to be in direct contact with two dielectric substrates and a filter using the resonator.
[0112]
The dielectric substrate has an fQ value of 3 × 10 at 1 GHz. ³ ~ 1x10 ⁵ Therefore, a resonator having a high Q value and a filter using the resonator can be provided.
[0113]
If the surface roughness of the dielectric substrate is in the range of 0.1 μm to 2.0 μm, and the amount of warpage of the surface of the dielectric substrate is 10 μm or less between both ends of the substrate, a metal foil is applied to the resonator electrode. Even if it is used, the metal foil can be brought into direct contact with the dielectric substrate in a wide range, thereby reducing the conductor loss and increasing the Q value of the resonator and the filter.
[0114]
In the method for manufacturing a dielectric resonator according to the present invention, a resonator electrode made of a metal foil is sandwiched between the main surfaces of the first and second dielectric substrates, and the two resonator electrodes are interposed. Since the resin bonding layer is formed by filling a resin adhesive between the main surfaces of the dielectric substrate and heating and curing the adhesive, the metal foil is brought into direct contact with the dielectric substrate in a wide range, thereby It is possible to manufacture a resonator and a filter with a reduced loss and an increased Q value of the resonator and the filter.
[0115]
In the method for manufacturing a dielectric resonator according to the present invention, except for the region where the resonator electrode is to be formed, the adhesive for forming the resin bonding layer is pattern printed, the adhesive is semi-cured, and the resonator electrode The conductive paste for forming the resonator electrode is printed and filled in the region where the electrode is to be formed, and the adhesive electrode and the conductive paste are completely combined by combining the resonator electrode of the first dielectric substrate and the second dielectric substrate. Since the resin bonding layer, the resonator electrode, and the dielectric substrate are integrated by curing, a resonator in which the resonance electrode of the conductive paste is in close contact with the dielectric substrate can be obtained, and has a high Q value. Resonators and filters can be manufactured.
[0116]
In the method for manufacturing a dielectric resonator according to the present invention, an adhesive film having a hollow portion hollowed out in the outer shape of the resonator electrode is prepared in the adhesive film, and a metal foil resonant electrode is disposed in the hollow portion. Then, the adhesive film is disposed between the first and second dielectric substrates, and the adhesive film is cured by applying pressure from the outer surfaces of the two dielectric substrates to cure the resin bonding layer. The dielectric substrate and the resonator electrode are integrated by a resin bonding layer to form a laminated body. Therefore, each dielectric resonator can be manufactured by cutting the laminated body into individual pieces, particularly an adhesive film. If a large number of resonators are fixed to a prepreg, a large number of resonators and filters can be mass-produced.
[Brief description of the drawings]
FIG. 1 shows an exploded perspective view (a) of a dielectric resonator according to an embodiment of the present invention and a longitudinal sectional view (b) of the dielectric resonator shown in FIG. 1 (a).
FIG. 2 is a longitudinal sectional view (a to f) showing a method for manufacturing a dielectric resonator according to an embodiment of the present invention.
FIG. 3 is a longitudinal sectional view (a to g) showing a method for manufacturing a dielectric resonator according to another embodiment of the present invention.
FIG. 4 is a longitudinal sectional view (a to g) showing a method for manufacturing a dielectric resonator according to another embodiment of the present invention.
FIG. 5 is a longitudinal sectional view (a to e) showing a method for manufacturing a dielectric resonator according to still another embodiment of the present invention.
FIG. 6 is a longitudinal sectional view (a to f) showing a dielectric filter manufacturing method according to still another embodiment of the present invention.
FIG. 7 is a cross-sectional view showing the shape of a resonator electrode of a dielectric resonator according to another embodiment of the present invention.
FIG. 8 is a block diagram of a wireless communication device in which a filter according to another embodiment of the present invention is connected between a transmission / reception shared antenna and a transceiver.
[Explanation of symbols]
2 Dielectric substrate
3 Dielectric substrate
4a Resonator electrode
4b Resonator electrode
5 Resin bonding layer

Claims (19)

  A step of sandwiching a resonator electrode made of a metal foil between the main surfaces of the first and second dielectric substrates, and a resin between the main surfaces of the two dielectric substrates generated by interposing the resonator electrodes A method for manufacturing a dielectric resonator, comprising: a step of filling an adhesive; and a step of forming a resin bonding layer by heat-curing the adhesive. A step of semi-curing the adhesive by pattern-printing an adhesive for constituting the resin bonding layer on the main surface of the first dielectric substrate that has been subjected to high-temperature firing, excluding the region where the resonator electrode is to be formed; ,
Printing and filling a conductive paste for forming a resonator electrode in a region where the resonator electrode is to be formed;
The main surface of the second dielectric substrate is disposed on the resonator electrode of the first dielectric substrate so as to be opposed to the first dielectric substrate, and the first and second dielectric substrates are heated while being pressed from the outer surface. A step of completely curing the adhesive and the conductive paste and integrating the resin bonding layer, the resonator electrode, and the dielectric substrate;
A method for manufacturing a dielectric resonator comprising: Preparing an adhesive film having a hollowed portion that is hollowed out in the outer shape of the resonator electrode in the adhesive film, and disposing a metal foil resonant electrode in the hollowed portion;
Disposing the adhesive film between first and second dielectric substrates;
The adhesive film is cured by applying pressure from the outer surfaces of the two dielectric substrates to form a resin bonding layer, and the dielectric substrate and the resonator electrode are integrated by the resin bonding layer to form a laminate. Forming, and
A method for manufacturing a dielectric resonator comprising: In the adhesive film, a large number of the punched-out portions are formed, and resonator electrodes are arranged in the punched-out portions, respectively.
4. The manufacturing method according to claim 2 , further comprising a step of cutting the laminated body and separating it into dielectric resonators after the step of forming the laminated body. The manufacturing method according to any one of claims 1 to 3, wherein the manufacturing method further includes a step of firing the green sheet containing the ceramic dielectric powder at a high temperature to form the dielectric substrate. The manufacturing method according to claim 1, wherein the resonator electrode is at least two parallel stripline resonators. The manufacturing method according to claim 1, wherein the dielectric substrate is made of a dielectric having an fQ value in a range of 3 × 10 ³ to 1 × 10 ⁵ at 1 GHz. The dielectric substrate is an oxide of Zr—Ti—Mg—Nb—O, Bi—Nb—O, Ba—Ti—O, Ba—Nd—Ti—O, or Ba—Sm—Ti—O. The manufacturing method according to any one of claims 1 to 7, comprising the dielectric material. The surface roughness of the dielectric substrate is in the range of 0.1Myuemu～2.0Myuemu, warpage of the surface of the dielectric substrate, between both ends of the substrate, any one of claims 1 to 8 is 10μm or less The manufacturing method as described in. The process according to any one of claims 1 and 3 to 9 the metal foil resonator electrodes, characterized by comprising a metal foil containing a copper-based or silver. 10. The manufacturing method according to claim 2, wherein the resonator electrode conductive paste is made of a paste obtained by mixing a metal powder containing copper or silver as a main component and an organic binder. The manufacturing method according to claim 6 , wherein the resonator electrode has a wide portion on an open end side of each stripline resonator. The manufacturing method according to claim 1, wherein the resonator electrode has a thickness of 50 μm to 400 μm. The manufacturing method according to any one of claims 1 to 13 , wherein the resin adhesive has a dielectric constant equal to or less than 1/4 times that of the dielectric substrate. The manufacturing method according to any one of claims 1 to 13 , wherein the adhesive or the adhesive film is a composite material composed of a thermosetting resin and an inorganic filler mixed with the resin. A metal paste for forming an interstage coupling capacitive electrode is disposed between green sheets containing ceramic dielectric powder, and is fired at a high temperature to produce either one of the dielectric materials of the first and second dielectric substrates. Forming a body substrate;
Placing a metal paste for forming capacitive coupling electrodes for input and output between green sheets containing ceramic dielectric powder, and firing the high temperature to form the other dielectric substrate; Then
A method for manufacturing a dielectric resonator according to any one of claims 1 to 14 ,
Including
A method of manufacturing a dielectric filter in which the resonator electrodes are electromagnetically coupled to each other, and an input terminal and an output terminal are coupled to the resonator electrode. The manufacturing method according to claim 16 , wherein the manufacturing method further includes a step of previously forming an external electrode on the dielectric substrate. The manufacturing method according to claim 16 , wherein the manufacturing method includes a step of forming an external electrode on the outer surface of the dielectric substrate of each cut dielectric resonator. The external electrode electrolytic plating method according to claim 17 or 18 formed by an electroless plating method or spraying method.

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